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Cheiraster cf. echinulatus (Perrier, 1875) Figure 4C This species was observed partly buried with its superomarginal edge lying flush alongside the surface of the bottom sediment. Other species of benthopectinids have been observed during Okeanos Explorer cruises sitting out on open substrates (Mah, unpublished observations), making this the first to be seen buried in the sediment with its spines projecting upwards, suggesting that they are used for defense, perhaps while the animal feeds on underlying sediment or sediment-related prey. Image Observed Pourtales Terrace, Gulf of Mexico, 24.28439, -82.25347, 332 m. EX1803_IMG_20180502T192533Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on page 212, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018

SOLASTERIDAE The systematics of Atlantic coast Solaster spp., as summarized by Clark and Downey (1992) are in need of revision with many species showing overlapping character limits. The widely occurring Solaster endeca for example, varies from Solaster earlii on the basis of only a few furrow and subambulacral spine count differences as well as the R/ r ratio. Without launching into a full revision, which is beyond the scope of the work herein, specimen variation of Atlantic Solaster spp. suggests that the taxonomic limits of these species are more tenuous than historical accounts have suggested.

Sthenaster emmae Mah et al. 2010 Figure 17 A���D In situ images of this species were identified based on the distinctive arrangement of abactinal plates as well as the wide superomarginal interradial plates. This is contrasted with those in Gilbertaster which are more elongate. Color in life of this species is white on the disk surface with darker orange plates. Arms are a more solid colored light orange. A second morphotype, of what is interpreted as a smaller individual was a uniform pink-brown in color. New observations of this species in conjunction with the extensive survey observations of Okeanos Explorer throughout the Gulf of Mexico and adjacent regions show occurrence to be limited to the southeastern coastal region of North America, specifically, the Savannah Banks and Central Plateau Scarp region. Feeding & Other Observations Imagery collected by the Okeanos Explorer are the first clear observations of this species in situ and apparently feeding on prey. Initial determination of the predatory status of Sthenaster emmae was based primarily on gut contents of the holotype, which included spicules from Eunicella modesta (Verrill 1883) as well as unclear video. Video observations captured one small individual on a denuded stalk projecting from dead Lophelia. Other imagery captured Sthenaster with a swollen disk possibly hunched over an unidentified prey item. Occurrence: Savannah Banks and off the coast of Jacksonville, FL, Central Plateau Scarp and Richardson���s Jellyfish, 252��� 874 m. Images Examined Central Plateau Scarp, 30.924592, -78.088036, 874 m, EX 1903L2_IMG_20190629 T 165108Z_ ROVHD.jpg (small individual) Central Plateau Scarp, 30.925962, -78.089989, 865 m, EX 1903L2_IMG_20190629 T 184639Z_ ROVHD.jpg (swollen) Central Plateau scarp, 30.924906, -78.088884, 870 m EX 1903L2_IMG_20190629 T 173638Z_ ROVHD.jpg (swollen) Richardson���s Jellyfish, 30.924993, -78.089565, 865 m, EX 1903L2_IMG_20190701 T 180214 Z_ ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 237-238, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Mah, C. L., Nizinski, M. & Lundsten, L. (2010) Phylogenetic Revision of the Hippasterinae (Goniasteridae; Asteroidea): Systematics of Deep Sea Corallivores, including one new genus and three new species. Zoological Journal of the Linnean Society, 160, 266 - 301, 11 figs. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00638. x"]}

Circeaster americanus (A.H. Clark 1916) Figure 7 A���C Circeaster americanus is a widely occurring species throughout the western North Atlantic, with occurrence recorded throughout the tropical Atlantic to the mid-Atlantic Ridge (Mah 2015). Most Circeaster diversity is known primarily in the Indo-Pacific where it is represented by eight species. Two of the most closely related species to C. americanus, Circeaster pullus Mah 2006 and Circaster sandrae Mah 2006 occur in the north and south Pacific, respectively. Morphological variation was observed in this species across its range. The Caribbean form (Fig. 7A, 721 m) showed slender arms and demonstrated a closer resemblance to the Pacific species, such as C. pullus and C. sandrae. In contrast, two individuals from the Gulf of Mexico (694-1133 m) displayed massive and strongly developed marginal plate series with thicker and more broadly triangular arms. Feeding Observations This species was observed feeding on three occasions. Observations showed predation on two different types of octocoral species. One observation (721 m) showed an individual with an arm upturned adjacent to a denuded Chrysogorgia colony. The other two observations (693 m and 1133 m) showed an individual slightly askew on a rock with a denuded isidid stalk emerging from below its oral region with the deeper observation (1133 m) showing an individual perched upon the upper branches of a denuded isidid coral skeleton. Circeaster americanus has previously been reported feeding on a fallen soft coral colony in the genus Paragorgia from Manning Seamount in the North Atlantic (Mah 2015). The diversity of prey items suggests this species displays broad variation with regard to its feeding preferences. Alternatively, it is possible that different cryptic lineages may have different feeding preferences but no data is available for the population phylogeography of this species. Occurrence Tropical Atlantic, Florida, Louisiana, Gulf of Mexico, North Carolina and the Caribbean, including Columbia, the Grenadines, Leeward Islands, Nicaragua, Netherlands, Antilles, St. Vincent, Suriname and Venezuela. North Atlantic, Manning Seamount, 500���1675 m. Images Examined Okeanos Ridge, Gulf of Mexico, 25.68007, -84.62041, 721 m EX1711_IMG_20171202T 150207 Z_ROVHD.jpg (Chrysogorgia) Okeanos Ridge, Gulf of Mexico, 25.68030, -84.61918, 694 m EX1711_IMG_20171202T 170721 Z_ROVHD.jpg (bamboo) Mona South Ridge, Caribbean Sea, 17.946907, -67.887304, 1133 m EX1811_IMG_20181117T155851Z_ROVHD.jpg (feeding), Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 218-219, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Clark, A. H. (1916) A new starfish (Lydiaster americanus) from the Gulf of Mexico. Journal of the Washington Academy of Sciences, 6, 141 - 144 https: // doi. org / 10.5962 / bhl. part. 10912","Mah, C. L. (2006) Phylogeny and biogeography of the deep-sea goniasterid, Circeaster (Echinodermata: Asteroidea) including descriptions of six new species. Zoosystema, 28 (4), 917 - 954."]}

Gilbertaster caribaea (Verrill 1899) Figure 12 A���E Observations made during expedition EX1903L2 are the first living observations of this species alive and in several cases, feeding. These individuals were recognized based on the elongate shape of the interradial marginal plates, the dense cover of coarse granules covering the marginal plates as well as the elongate arm shape. The image of the oral surface showed the distinctive series of bivalve pedicellariae present adjacent to the tube foot groove. The collected specimen is largely consistent with the description of the species as outlined in Mah et al. (2010). Gilbertaster (formerly Hippasteria) caribaea was assigned to Gilbertaster by Mah et al. (2010). Prior to that, Gilbertaster was known only from the Pacific. Video observations detailed herein confirm speculation of Gilbertaster as a corallivore. Color in life for this species is orange. Feeding & Ecological Observations Four observations of Gilbertaster caribaea feeding on primnoid octocorals were made (Figs 12 A���D). Two of these octocorals were identified as Plumarella sp. (12A,B). Feeding behavior for this species is similar to other octocoral predators in that the body is positioned over the octocoral so that its stomach can be directly applied onto the prey. Primnoids appear to show a more frond-like, softer morphology relative to isidid octocorals and appear to be more actively engulfed by the sea stars rather than climbed upon as seen in Circeaster and Evoplosoma. Deep-Sea Amphipod Association Two independent observations of Gilbertaster caribaea have shown 6 to 8 purple amphipods present in association with the tube feet and the oral surface (Fig. 12A,E). The first observation from Richardson Ridge at 797 m, (Fig. 12A) shows Gilbertaster feeding on Plumarella, a primnoid octocoral with its cardiac stomach and tube feet extended onto the prey item. Amphipods were observed in contact with the Plumarella stalk as well as folds of the stomach. It was unclear if they were simply hanging onto the star or the prey item or if they were feeding. A second observation was made on the Central Plateau Scarp at 886 m (Fig. 12E) and showed at least six amphipods irregularly distributed around the oral surface of an individual sitting on its side with its oral surface facing into the water. All of these amphipods were situated either on or adjacent to the tube foot grooves of the animal. The Richardson Ridge observations suggest commensalism or kleptoparasitism by the amphipods on the star as it devours the octocoral tissue. Alternative explanations include predation on the star���s tissue (i.e. stomach and/or tube feet) or even defense by the amphipods against the predator. Glynn (1983) described crustacean ���guards��� as host symbionts of shallow-water tropical coral, which defend their hosts against attacking sea stars by snapping and pinching. The Central Plateau Scarp observation showed the animal with its oral surface, including tube feet presented upwards into the water. This might represent the animal attempting to divest itself of the amphipods, assuming that present deleterious effects to the star, or are a source of irritation. The numerous pedicellariae on the surface of Gilbertaster might represent a defensive mechanism against these amphipods and/or other small crustaceans. Interestingly, Gale et al. (2013) noted amphipods as part of the stomach contents in Hippasteria phrygiana, another deep-sea hippasterine corallivore. They attributed these amphipods to occasional bottom feeding by H. phrygiana. It is unclear if the amphipods observed on Gilbertaster demonstrate similar behavior to those seen in the gut contents of Hippasteria phrygiana and whether the amphipods presence in the gut might be explained by the behavior observed in the deep-sea species on Gilbertaster. Images Examined On Plumarella Richardson Ridge, Gulf of Mexico, 31.769835, -77.362993, 797 m EX1806_IMG_20180621T193141Z_ROVHD.jpg (amphipods) EX1806_IMG_20180621T193400Z_ROVHD.jpg Also feeding on Plumarella ? Richardson Ridge, Gulf of Mexico, 31.770062, -77.363763, 782 m, EX1806_ IMG_20180621T205519Z_ROVHD.jpg, On octocoral Richardson Ridge, Gulf of Mexico, 31.769577, -77.363013, 781 m EX1806_IMG_20180621T195555Z_ROVHD.jpg Central Plateau Scarp. (with amphipods on oral surface), Off SE coast of United States. 30.923732, 78.087175, 901 m, EX1903L2_IMG_20190629T155659Z_ROVHD.jpg wrapped around coral. Central Plateau Scarp, off SE coast of United States. 30.924116, -78.087582, 886 m, EX1903L2_IMG_20190629T162255Z_ROVHD.jpg. Specimen Examined: USNM 1580844 Richardson���s Jellyfish, 32.0891, -77.6703, 592 m, Coll. A. Weinnig, with ROV Deep Discoverer, aboard NOAA Ship Okeanos Explorer. EX1903L2_IMG_20190701T195409Z_ROVHD. jpg 1 wet spec. R=8.0 r=2.6, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 228-230, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Verrill, A. E. (1899) Revision of certain genera and species of starfishes, with descriptions of new forms. Transactions of the Connecticut Academy of Arts and Sciences, 10 (1), 145 - 234. https: // doi. org / 10.5962 / bhl. part. 7031","Mah, C. L., Nizinski, M. & Lundsten, L. (2010) Phylogenetic Revision of the Hippasterinae (Goniasteridae; Asteroidea): Systematics of Deep Sea Corallivores, including one new genus and three new species. Zoological Journal of the Linnean Society, 160, 266 - 301, 11 figs. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00638. x","Glynn, P. W. (1983) Crustacean symbionts and the defense of corals: coevolution on the reef? In: Nitecki, M. H. (Ed.), Coevolution. University of Chicago Press, Chicago, Illinois, pp. 111 - 178.","Gale, K. S. P., Hamel, J. - F. & Mercier, A. (2013) Trophic ecology of deep-sea Asteroidea (Echinodermata) from eastern Canada. Deep-Sea Research I, 80, 25 - 36. https: // doi. org / 10.1016 / j. dsr. 2013.05.016"]}

Poraniomorpha abyssicola (Verrill 1895) Fig. 5C This species was identified by the highly rugose surface texture, cylindrical arms and the series of actinolateral spines present around the lower edge of the body. This represents the first observation of this species alive and in situ. Color in life was white with yellow highlights (Fig. 5C). Poraniomorpha abyssicola was observed perched on what appeared to be a demosponge on the Blake Ridge dive site at 3403 m. This is the first observation of this species apparently feeding. Occurrence: North Atlantic (west side) from latitude of Cape May to Cape Charles (c. 38.5- 37��N), Hudson Canyon. Blake Ridge, 2976���3740 m. Images Observed Blake Ridge, North Atlantic (off S. Carolina) 32.01258, -75.25909, 3403 m EX1806_IMG_20180615T152839Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on page 215, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Verrill, A. E. (1895) Distribution of the echinoderms of north-eastern America. American Journal of Science, 3 (49), 127 - 141. https: // doi. org / 10.2475 / ajs. s 3 - 49.290.127"]}

Remaster palmatus (Perrier 1881) Figure 20A This and other observations of this species during EX 1905L2 represent the first known in situ observations of this species. Observations herein show individuals hunched over sponge-covered substratum suggesting that they are almost certainly a food source. Remaster palmatus is one of two species within the genus Remaster, the other species, Remaster gourdoni Koehler 1912 is known primarily from the Antarctic. The Korethrasteridae are members of the Velatida, which includes the Myxasteridae and the Pterasteridae. Images Observed 28 June, Stetson Mesa Terrace, North Atlantic, 31.594604, -79.102624, 445 m, (both files) EX1903L2_IMG_20190628T164834Z_ROVHD.jpg EX1903L2_IMG_20190628T162943Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on page 243, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Perrier, E. (1881) Report on the Results of dredging in the Gulf of Mexico and in the Caribbean Sea, 1877 - 79, by the United States Coastal Survey Steamer Blake. 14. Description sommaire des especes nouvelles d'Asteries. Bulletin of the Museum of Comparative Zoology, 9, 1 - 31.","Koehler, R. (1912) Echinodermes nouveaux recueillis dans les mers antarctiques par le ' Pourquoi Pas? ' (Asteries, Ophiures et Echinides). Zoologischer Anzeiger, 39, 151 - 163. https: // doi. org / 10.5962 / bhl. title. 85347"]}

Cladaster rudis Verrill 1899 Figure 8 A���D This species was identified based on its triangular arms and coarse granules covering the abactinal and marginal plate surfaces, superomarginals abutted over the mid radius on each arm, the large single subambulacral spine and the pedicellariae type present on the actinal surface. The sample collected was obtained from a region near the type locality and was morphologically very similar in terms of the abactinal and marginal surface granulation and plate and arm plate morphology. The specimen had much rounder granules on the actinal surface versus the holotype which had more pointed and conical granules on the surface. Pedicellariae also seemed to be more abundant on the specimen mentioned herein. Feeding Observations On three of the four observations that this species was observed, it was positioned vertically on a small branched Lophelia colony upon which it was apparently feeding (Fig. 8A). Polyps from the colony were withdrawn with most of the colony seemingly lifeless. One of the Stetson Mesa West observations observed a Cladaster present on a laterally positioned Lophelia colony with its disk and arms arched around it. This represents the first in situ feeding observation of Cladaster rudis. Occurrence: Off Florida, Stetson Mesa North and West, Blake Plateau, Yucatan Channel. 150��� 900 m. Images Examined Stetson Mesa North, North Atlantic 30.40337, -79.59817, 787 m. EX1806_IMG_20180620T 151009 Z_ROVHD.jpg Stetson Mesa West 29.859987, -79.455657, 767 m. EX1907_IMG_20191103T205656Z_ROVHD.jpg Stetson Mesa West 29.861274, -79.45494, 785 m. EX1907_IMG_20191103T185505Z_ROVHD.jpg Material Examined USNM 1607547 Stetson Mesa Mound Field One, 30.399, -79.2757, 824 m, Coll. ROV Deep Discoverer, NOAA Ship Okeanos Explorer, EX 1907. 4 Nov. 2019. 1 wet spec. R=1.9 r=1.0. EX1907_IMG_20191104T175744Z_ ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on page 219, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Verrill, A. E. (1899) Revision of certain genera and species of starfishes, with descriptions of new forms. Transactions of the Connecticut Academy of Arts and Sciences, 10 (1), 145 - 234. https: // doi. org / 10.5962 / bhl. part. 7031"]}

PORANIIDAE Comments As summarized by Mah and Foltz (2012), poraniids were previously thought to be ciliary suspension feeders but ongoing evidence has shown multiple poraniids displaying predatory habits. Observations by the Okeanos Explorer have identified at least two species displaying spongivorous habits. Other observations of deep-water poraniids include the Pacific Bathyporania ascendens feeding on antipatharians (Mah and Foltz 2014) and Porania pulvillus feeding on alcyonaceans (Ericsson & Hansson, 1973). Under aquarium conditions, Chadwick (1916) has reported Porania pulvillus attacking and devouring sea anemones (Adamsia palliata).

Henricia antillarum (Perrier 1881) Figure 19 A���D Comments This species was initially recognized in the field based on its elongate, somewhat attenuated arms which are broadened basally as well as a relatively large actinal intermediate area with plates bearing small spinelets. Furrow spines were three to four. Observed specimens were white differing from the ���orange-yellow��� color outlined by Clark and Downey (1992). Feeding Observations Henricia antillarum is a predator on sponges, having been observed twice feeding on two different sponge taxa, including a hexactinellid (Fig. 19A) and a cladorhizid or carnivorous sponge, which appears to be Chondrocladia sp. or a similar taxon (Fig. 19B, USNM 1607572 Off Key West). Henricia spp. was widely observed as a predator on several sponge taxa in the Pacific by NOAA Ship Okeanos Explorer in the Pacific during the CAPSTONE campaign (Mah, unpublished data). Shallow-water Henricia sp., such as H. sanguinolenta have been documented as sponge predators (e.g. Sheild & Witman 1993). Robertson et al. (2017) reported that the deep-water Atlantic Henricia lisa is a predator on sponges. Occurrence: Georgia, south to the Florida Strait, Yucatan Channel to northern Brazil. 275-1390 m. Images Examined Central Blake Plateau, 30.761523, -78.745073, 766 m EX1907_IMG_20191106T172446Z_ROVHD.jpg Material Examined: USNM 1607572 Key Largo Deep, North Atlantic. 24.7718, -80.1484, 601 m, Coll. NOAA Ship Okeanos Explorer, Southeastern US Deep-Sea Exploration EX1907, 16 Nov 2019. 1 wet spec. R=8.8 r=1.2. EX1907_IMG_20191116T190746Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 241-243, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Perrier, E. (1881) Report on the Results of dredging in the Gulf of Mexico and in the Caribbean Sea, 1877 - 79, by the United States Coastal Survey Steamer Blake. 14. Description sommaire des especes nouvelles d'Asteries. Bulletin of the Museum of Comparative Zoology, 9, 1 - 31.","Clark, A. M. & Downey, M. E. (1992) Starfishes of the Atlantic. Chapman and Hall, London, 794 pp.","Sheild, C. J. & Witman, J. D. (1993) The impact of Henricia sanguinolenta (O. F. Muller) (Echinodermata: Asteroidea) predation on the finger sponges, Isodictya spp. Journal of Experimental Marine Biology and Ecology, 166 (1), 107 - 133. https: // doi. org / 10.1016 / 0022 - 0981 (93) 90081 - X","Robertson, L. M., Hamel, J. - F. & Mercier, A. (2017) Feeding in deep-sea demosponges: Influence of abiotic and biotic factors. Deep-Sea Research, Part I, 127, 49 - 56."]}

Plinthaster dentatus (Perrier 1884) Figure 14D Comments Plinthaster dentatus occurs widely on both the eastern and western sides of the Atlantic Ocean as far south as the Gulf of Guinea (Clark & Downey 1992) and is quite variable across its range (Halpern 1970, Clark & Downey 1992). H.E.S. Clark (2001) has reported Plinthaster dentatus from the Kermadec Islands, north of New Zealand. Confirmation of this latter account should be reviewed in the context of a global revision of Plinthaster species. Three non-Atlantic species of Plinthaster are known, including Plinthaster ceramoidea Fisher 1906 from the North Pacific (Fisher 1906, Mah 2015) and Plinthaster lenaigae Mah 2018 and Plinthaster unteidtae Mah 2018 from the western Indian Ocean (Mah 2018). Although well represented in museum collections, relatively little data is available for life habits or other aspects of its biology. Feeding Observation This species was identified on Madrepora rubble where it appeared to be feeding on encrusting organisms. It was also present in the multi-taxon feeding observation described herein, feeding on the larger of the two geodiid sponges (Fig. 20). Occurrence: Atlantic: North Carolina, Gulf of Mexico (Florida, Louisiana, Texas), Bahamas, Venezuela, Dominican Republic, Jamaica, Anguilla, Nicaragua, Columbia, Gudeloupe, St. Vincent and Grenadines, Honduras, Trinidad and Tobago, Mexico, Panama, to northern Brazil. Rockall Trough, Newfoundland to Gulf of Guinea, Azores, Canary and Cape Verde Islands, Faroe Islands. South Pacific: Kermadec Islands(?). 229���2910 m. Image Observed Stetson Mesa Seep, 30.436107, -79.582, 814 m EX1903L2_IMG_20190627T153648Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 232-233, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Perrier, E. (1884) Memoire sur les etoiles de mer recueillies dans la mer des Antilles et le golfe du Mexique: durant les expeditions de dragace faites sous la direction de M. Alexandre Agassiz. Archives (Museum national d'histoire naturelle, France), 2 (6), 127 - 276. https: // doi. org / 10.5962 / bhl. title. 82184","Clark, A. M. & Downey, M. E. (1992) Starfishes of the Atlantic. Chapman and Hall, London, 794 pp.","Halpern, J. A. (1970) Biological investigations of the deep sea. 51. Goniasteridae (Echinodermata: Asteroidea) of the Straits of Florida. Bulletin of Marine Science, 20 (1), 193 - 286.","Fisher, W. K. (1906) The starfishes of the Hawaiian islands. Bulletin of the United States Fish Commission, 23, 987 - 1130.","Mah, C. L. (2018) New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean. Zootaxa, 4539 (1), 1 - 116. https: // doi. org / 10.11646 / zootaxa. 4539.1.1"]}

Sibogaster bathyheuretor n. sp. Figures 15 A���E, 16A���D Etymology The species epithet is a combination of the Greek bathys and heuretor for ���deep discoverer��� and honors the ROV Deep Discoverer which collected this and many other Okeanos Explorer species. Comments This species is similar to a widely distributed species described by Mah (2016) from abyssal settings (> 2000 m) in the Atlantic and the North and Central Pacific. This represents the first occurrence of Sibogaster from the Gulf of Mexico. Although Sibogaster nieseni has been imaged in the Pacific, this represents the first in situ observation of this genus from the Atlantic. Ecological Observations This species was observed feeding on a wide range of possible food and prey items, primarily from the West Florida Escarpment. One observation at 2192 m showed an individual perched on a denuded black coral stalk, having apparently digested the living tissue (Fig. 16C). A subsequent observation at 2138 m shows this species present between sargassum and elongate glass sponge spicules (Fig. 16D). This latter observation likely represents the animal feeding either on the sargassum or epizoic on the sargassum. The collected specimen from the West Florida Escarpment (USNM 1507293) was observed elevated above the sediment surface and feeding on unidentified subject below it (Fig. 16A). Following collection of the specimen however, no evident prey was observed attached to the mouth and the substrate the animal was sitting on showed no evident prey item. Its possible the animal was feeding on sediment, or possibly a sedimentary structure such as the test from a xenophyophoreans (Foraminifera). The Perdido Canyon observation showed the specimen with its lower surface buried into what appeared to be flocculent sediment suggesting deposit feeding by the animal (Fig. 16B). Occurrence: Perdido Canyon and West Florida Escarpment, Gulf of Mexico. 2597���2777 m. Description Body stellate (R/r=2.07) with broadly curved to straight interradial arcs. Arms triangular with pointed tips. Specimen with one arm regenerating. Abactinal plates flat, round to polygonal in outline with smooth, bare surface. Plates with one to four small crystal bodies centrally on each plate. Each plate with 10���50 small quadrate granules, forming a wide periphery around each plate. Granules taking about 10% of the total diameter. Granules centrally on disk becoming more abundant especially within the primary circlet. Plates larger and more circular proximally becoming smaller, more ovate and irregular in shape distally adjacent to superomarginal plate contact. Abactinal plates extend from disk along arm where distalmost superomarginal plates are abutted becoming weakly convex on arms. Madreporite strongly convex with well developed sulci. Madreporite with two to four series of granules forming periphery around it, flanked by six to eight abactinal plates. Marginal plates extending away from abactinal surface. Anus located centrally on disk but surrounded by approximately 10 granules closely arranged around it, but more open when observed in situ. Superomarginals 20 per interradius, from arm tip to arm tip, 20���21 inferomarginals, slightly offset from superomarginals distally but with 1:1 correspondence proximally. Superomarginal surface with mostly bald, smooth quadrate surface, remaining lateral region on superomarginal plate with 10���30, mostly ~20, round, evenly distributed granules. In situ observations show interradial superomarginals with widely spaced 40 to 200 round granules with pointed tips becoming bare and smooth distally. Inferomarginals with 100���400 round to pointed granules, widely distributed. One or two interradial inferomarginal plates with small paddle-like pedicellariae (about 1.0 mm in length). Small peripheral granules, approximately 20 per side, total, approximately 80���150 in total. Distalmost two or three superomarginals abutted over midline. Terminal plate triangular in shape, similar in size to one adjacent superomarginal plate. Actinal surface flat, composed of approximately 2 full series in chevron-like format with one or two irregular, incomplete series present distally adjacent to inferomarginals. Individual plates quadrate to irregular in shape. Surface with 10���50 widely spaced granules, ranging from round to angular and pointed. Smaller peripheral granules, approximately five to eight per side, totaling 20 to 40, central granules larger, more irregular. Granules similar in size and distribution with those on inferomarginal surface. Furrow spines seven to eight in a straight to weakly curved fan, spines blunt-tipped. A single large paddleshaped subambulacral pedicellariae present immediately adjacent to furrow spines on first six adambulacral plates. Pedicellariae the size of two to three adjacent granules.Adambulacral plate surface around pedicellariae smooth and clear of accessories. First adambulacral plates with largest pedicellariae. Adambulacral plate surface with one or two regular series, each with three to five pointed or angular granules, widely spaced, separated from pedicellariae by discrete space. Distalmost six to eight adambulacral plates with prominent spine, blunt, cylindrical in cross-section becoming larger near am tip. Oral plates with 14 furrow spines, flattened to quadrate in cross-section with a single prominent spine projecting into the mouth, one per plate (thus two per interradius). Oral plate surface adjacent to furrow spines bare and smooth. Fossae between paired oral plates with tissue, granules eight to ten, paired on each side. Prominent paired spines as part of granule series on each half of the oral plate series. Oral plates with five to seven widely spaced angular plates around periphery in contact with adjacent actinal plates. Color in life, white on disk with central orange on each plate. Marginals and arm plates dark orange. Regenerating arm white to light orange. Comparisons This species is distinguished primarily based on the differences along the adambulacral plate accessories. Sibogaster n.sp. lacks the larger subambulacral spines observed in S. nieseni and possesses pedicellariae on the surface of the adambulacral plate which are paddle-shaped and different from the more tong-shaped pedicellariae in Sibogaster nieseni. Images Observed Perdido Canyon, Gulf of Mexico, 26.1466, 94.86662, 2777 m, EX1803_IMG_20180418T164814Z_ROVHD.jpg DeSoto Canyon, Gulf of Mexico, 28.28367, -87.22315, 2629 m EX1803_IMG_20180425T151605Z_ROVHD.jpg black coral. West Florida Escarpment, Gulf of Mexico 24.91709, -84.49052, 2192 m EX1803_IMG_20180430T161527Z_ROVHD.jpg West Florida Escarpment, Gulf of Mexico 24.91523, -84.4933, 2138 m EX1803_IMG_20180430T183436Z_ROVHD.jpg Material Examined Holotype. USNM 1507293 West Florida Escarpment, Gulf of Mexico, 27.71516, -85.74739, 2597 m, Coll. D. Wagner, with ROV Deep Discoverer aboard NOAA Ship Okeanos Explorer. 1 wet spec. R=2.7 r= 1.3. 27 April 2018. EX1803_IMG_20180427T 210536 Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 234-237, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Mah, C. L. (2016) Deep-sea (> 1000 m) Goniasteridae (Valvatida; Asteroidea) from the North Pacific, including an overview of Sibogaster, Bathyceramaster n. gen. and three new species. Zootaxa, 4175 (2), 101 - 141. https: // doi. org / 10.11646 / zootaxa. 4175.2.1"]}

Solaster sp. 1 Figure 18E This species was stellate (R/r=~2.1���2.4) possessed a thick disk with nine relatively short, tapering arms. Abactinal paxillae weakly developed, but widely spaced on the surface. Each arm with approximately 20���30 evenly spaced paxillae, per side (40 to 60 from arm tip to arm tip) each with approximately three to six spinelets forming the actinolateral boundary. Color varied from orange to bright magenta-red. Crab Associate & Ecological Notes This red species was observed on a flat, muddy plain populated by what appeared to be ophiuroids with elongate arms possibly Ophiomusa lymani. Jangoux (1982) have indicated ophiuroids as a prey items for Solaster endeca, which is similar in appearance. This species hunting for ophiuroids would be consistent with the fact that while most asteroid observations are solitary, two individuals of this species are present within 60 cm of one another. The orange colored Solaster sp. 1 individual showed a small lithodid crab present on the abactinal surface of one arm. This area was significantly discolored and was a distinct white color as opposed to the darker orange on the remainder of the body. Its unclear if the crab had been feeding upon the surface tissue of the star or if the discoloration could have originated as a result of constant movement by the crab on that specific region of the arm.Although no accounts of deep-sea lithodid predation on asteroids were located, the shallow-water lithodid crab Paralithodes camtschatica has been observed to attack and feed on the asteroid Pycnopodia helianthoides (Feder, 1980). Occurrence: Pamlico Canyon Ridge, 1587���1673 m. Images Examined brittle star field. Pamlico Canyon Ridge, North Atlantic 34.77461, -75.3424, 1673 m EX1806_IMG_20180625T141433Z_ROVHD.jpg EX1806_IMG_20180625T141541Z_ROVHD.jpg with crab. Pamlico Canyon Ridge, North Atlantic 34.77497, -75.34556, 1587 m EX1806_IMG_20180625T165230Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 239-241, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Jangoux, M. (1982) Food and feeding mechanisms: Asteroidea. In: Jangoux, M. & Lawrence, A. A. (Eds.), Echinoderm Nutri- tion. Balkema Rotterdam, pp. 117 - 159.","Feder, H. M. (1980) Asteroidea: The Sea Stars. In: Morris, R. H., Abbott, D. P. & Haderlie, E. C. (Eds.), Intertidal Invertebrates of California. Stanford University Press, Stanford, pp. 117 - 135."]}

Evoplosoma sp. 1 Figure 10E This species is similar to the holotype and description of Evoplosoma virgo as presented by Downey (1982). The numerous polygonal plates with granules present on the central surface are more widely distributed in the observed specimen, but are densely packed on the holotype. No primary spines were observed on the abactinal surface. The observed species differs in having bare superomarginal plates and having a complete series of prominent spines located on each plate across the complex interradius. Evoplosoma virgo has superomarginal plates covered by a dense granules and lacks spines interradially, displaying spines only on the distalmost superomarginals along the arm. Similarly, Evoplosoma scorpio also has marginal plates covered by granules, ruling it out as a contender Evoplosoma sp. 1. This species is similar to Evoplosoma sp. 2 but lacks the abactinal spines present on the disk and arm surface. Body color was also different, as this species was a deep red-orange whereas Evoplosoma sp. 2 was a light yellow with darker orange arms. Feeding Observation This species was observed on a sedimented substrate with its arms holding up its body as its disk was suspended over what appeared to be a primnoid octocoral in the genus Callogorgia. Images Examined Blake Ridge, North Atlantic 32.01264, -75.26038, 3388 m EX1806_IMG_20180615T162553Z_ROVHD.jpg

PAXILLOSIDA Members of the Paxillosida are associated with burial in unconsolidated sediment and most families possess pointed tube feet and a number of other morphological adaptations for digging and living in mud or sand. Phylogenetic molecular revision by Mah and Foltz (2011b) has added families, such as the Pseudarchasteridae and the Benthopectinidae with unpointed tube feet to the Paxillosida suggesting a broader morphological range., Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on page 210, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Mah, C. L. & Foltz, D. W. (2011 b) Molecular Phylogeny of the Valvatacea (Asteroidea, Echinodermata). Zoological Journal of the Linnean Society, 161, 769 - 788. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00659. x"]}

Pythonaster atlantidis A.H. Clark 1948 Figure 20 B���E Pythonaster atlantidis is one of three species within Pythonaster, a rarely encountered genus in the Myxasteridae. Each of the known Pythonaster sp. is poorly understood and relatively few specimens are available for each species. Some species, such as the Atlantic Pythonaster murrayi are known only from the holotype. This account and the upcoming summary of the Okeanos Explorer CAPSTONE expedition will be the first published accounts documenting in situ observations of Pythonaster as well as observations of its feeding behavior. The observations herein document new occurrence of this species from the Gulf of Mexico. Pythonaster is recognized by the very distinct swollen proximal arm region, linear rows of ensacculate spinelets present along the surface of the arms, the thin body wall, and the continuously webbed actinolateral spine series present along the furrow of the arms. Details such as the number of spine clusters, 4 to 8 were counted from imagery, are consistent with descriptions of this species from trawled collections. Based on other observations of Pacific Pythonaster spp. individuals are mostly observed perched on vertical wall faces, especially hard rock surfaces. However, one specimen of Pythonaster, thought to be P. atlantidis was observed on soft substrates on the northwest Florida Escarpment at 1970 m. This specimen (Fig. 20B), at R=~15.0 (30.0 cm total diameter) had relatively swollen arms with a more cylindrical appearance with thicker, more homogeneous arms, but otherwise appeared consistent with other observed species, which tended to have more strongly swollen proximal arm regions and narrower more tapering distal arm regions. When observed in situ this species appears strongly inflated with seawater which apparently provides buoyancy to the ensacculate spines and other structures. All observed individuals of this species were white with a translucent body wall. The ambulacrals were visible and appeared as a brighter white than the body wall. The proximal arm regions had a very weak purple to violet highlight. Tube feet were white with bright white suckers. Feeding Observations This species was observed feeding on two different types of glass sponges (Hexactinellida) (Figs. C-E), with one observation from DeSoto Canyon, Gulf of Mexico at 2604 m (Fig. 20 C-D) and a second on Jaguey Spur at 2666 m, off the coast of Puerto Rico (Fig. 20E). The Gulf of Mexico feeding observation showed tube feet cardiac stomach extended, the latter with elaborate frilled folds around the edges, extending from two sides around the base of the sponge. The second feeding image from Puerto Rico showed the animal on the sponge surface, but with its disk slightly sunken, presumably extending its stomach onto the sponge tissue. Occurrence: Gulf of Mexico, Puerto Rico, South of Azores (35��37���N, 30��15���W), Hudson Canyon, North Atlantic (38��25���06���N, 70��52���, 30���W), Porcupine Abyssal Plain, 2604 ���4877 m Images Examined Escarpment Canyon, Gulf of Mexico EX1711_IMG_20171201T171312Z_ROVHD.jpg DeSoto Canyon, Gulf of Mexico, 28.28388, -87.22355, 2604 m (both below) EX1803_IMG_20180425T155302Z_ROVHD.jpg EX1803_IMG_20180425T155445Z_ROVHD.jpg (feeding on glass sponge) largest specimen, Northwest Florida Escarpment, Gulf of Mexico, 28.1254, -86.65615, 1970 m EX1803_IMG_20180426T184110Z_ROVHD.jpg Jaguey Spur, off coast of Puerto Rico 17.606345, -67.273602, 2668 m, EX1811_IMG_20181109T171906Z_ROVHD.jpg (on Rossellidae) glass sponge), Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 243-245, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Clark, A. H. (1948) Some interesting starfishes and brittle-stars dredged by the Atlantis in mid-Atlantic. Journal of the Washington Academy of Science, 38, 75 - 85."]}

Cidaris rugosa (H.L. Clark, 1907) Figures 21 A���B, 22A���B Cidaris rugosa was identified based on the spine shape, including the spine tip morphology as outlined in Phelan (1970). Occurrence of this species was based on Phelan (1970) and enhanced by USNM collection records and new occurrence from Pawson and Pawson (2013). Occurrence: Georgia, Louisiana, Gulf of Mexico, Bahamas, Belize, Cuba, Dominica, Puerto Rico, St. Martin, St. Lucia, Guadeloupe, St. Vincent and the Grenadines, Venezuela, Mexico 130���788 m Images Examined: See below., Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 245-247, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Clark, H. L. (1907) The Cidaridae. Bulletin of the Museum of Comparative Zoology, 51 (7), 165 - 230.","Phelan, T. (1970) A Field Guide to the Cidaroid Echinoids of the Northwestern Atlantic Ocean, Gulf of Mexico, and the Caribbean Sea. Smithsonian Contributions to Zoology, 40, 1 - 67. https: // doi. org / 10.5479 / si. 00810282.40","Pawson, D. L. & Pawson, D. J. (2013) Bathyal sea urchins of the Bahamas, with notes on covering behavior in deep sea echinoids (Echinodermata: Echinoidea). Deep Sea Research Part II: Topical Studies in Oceanography, 92, 207 - 213. https: // doi. org / 10.1016 / j. dsr 2.2013.01.023"]}

Ophidiaster guildingi Gray 1840 Figure 18 A���D This species was recognized as Ophidiaster based on the eight rows of papular rows present along each arm and confirmed as Ophidiaster guildingi based on the number of papular pores present in each papular area (10 to 15). It had a dark tan to yellow abactinal surface, with a white to lighter colored oral surface. This was a frequently encoun- tered species throughout the several Okeanos Explorer surveys and was one of the few species observed feeding on both sponges and corals, although most observations were of the former. Feeding Observations Two different sponges were seen as prey items. One large, unidentified demosponge from south of Okeanos Ridge at 424 m was observed with one individual present on one of its lobe-like surfaces (Fig. 18A). A second observation on Stetson Mesa Terrace showed an individual with one arm in contact with a hemispherical sponge, possibly in the genus Geodia sp. (Fig. 18C). A further observation from south of Okeanos Ridge at 435 m showed an individual with its disk perched over the calyx of an unidentified cup coral, apparently feeding upon it (Fig. 18D). These observations are the first of this species feeding and are among the first to show feeding in deep-sea ophidiasterids. Jangoux (1982) has summarized the prey items of several shallow-water ophidiasterid species with many of these species described as substrate film-feeders with one or two species described as feeding on encrusting organisms, or sponges. Occurrence: Florida, off the coast of Georgia, Texas, Bermuda, Bahamas, Puerto Rico, Belize, Turks and Caicos, Anguilla, Dominican Republic, Atlantic coast of Mexico (Quintana Roo), Virgin Islands, Trinidad and Tobago, Antilles, Atlantic side of Panama, Ascension Island and Cape Verde Islands south to Annobon Island, Gulf of Guinea. 0��� 445 m Images Observed South of Okeanos Ridge, Gulf of Mexico, 25.60547, -84.54973, 435 m EX1803_IMG_20180429T161419Z_ROVHD.jpg (cup corals) South of Okeanos Ridge, Gulf of Mexico, 25.60861, -84.54895, 424 m EX1803_IMG_20180429T 211131 Z_ROVHD.jpg (large sponge) South of Okeanos Ridge, Gulf of Mexico, 25.60506, -84.55012, 480 m EX1803_IMG_20180429T 150850 Z_ROVHD.jpg Stetson Mesa Terrace, 31.594732, -79.102572, 445 m EX1903L2_IMG_20190628T161824Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on pages 238-239, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Jangoux, M. (1982) Food and feeding mechanisms: Asteroidea. In: Jangoux, M. & Lawrence, A. A. (Eds.), Echinoderm Nutri- tion. Balkema Rotterdam, pp. 117 - 159."]}

Peltaster placenta (M��ller & Troschel, 1842) Figure 14 A���C Comments Peltaster is a widely occurring goniasterid, containing two Pacific and one Atlantic species, all of which display widespread occurrence. Peltaster placenta for example has been documented on both sides of the Atlantic and across a broad bathymetric range, from 10 to over 1000 m depths. Although differentiated from Ceramaster and Sphaeriodiscus, the morphological boundaries between these two genera and Peltaster has been historically difficult to establish (e.g. see Mah 2018). All three genera demonstrate pentagonal body shape with relatively large marginal plates and granule-covered abactinal plates. Sphaeriodiscus and Peltaster show close morphological similarity and further understanding of variation and phylogenetic relationships might result in synonymy of the two genera. Feeding Observation This species was observed perched upon an unidentified demosponges present among dead, Lophelia rubble in two observations (Figs. 14A, B). Small soft corals were also present along the surface of the sponge, suggesting that Peltaster could also have been feeding on these as well as the sponge. Peltaster placenta was also observed on a hexactinellid (glass) sponge (Fig. 14C), displaying feeding behavior. This species has also been reported feeding on antipatharians by Bo et al. (2018).Added discussion on Peltaster feeding is included in sponge feeding discussion below. Occurrence: Western Atlantic: Cape Cod region, Massachusetts, New York, Florida, Georgia, Louisiana, Antigua and Barbados, Bahamas, Jamaica, Puerto Rico, Guadeloupe, Venezuela, Eastern Atlantic: Norway (near Trondheimsfjord) south to the equator, Iceland, Mediterranean, including Tunisia. 10���1007 m. Images Observed Bajo de Sico, Puerto Rico, 18.292659, -67.460653, 310 m EX1811_IMG_20181114T214557Z_ROVHD.jpg EX1811_IMG_20181114T214637Z_ROVHD.jpg Stetson Mesa ���Seep���, 29.10912, -79.44749, 738 m EX1903L2_IMG_20190622T191837Z_ROVHD.jpg EX1903L2_IMG_20190622T192110Z_ROVHD.jpg 27 June, Stetson Mesa ���Seep���, 30.435198, -79.583484, 778 m EX1903L2_IMG_20190627T 170506 Z_ROVHD.jpg, Published as part of Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, pp. 201-260 in Zootaxa 4766 (2) on page 232, DOI: 10.11646/zootaxa.4766.2.1, http://zenodo.org/record/3764018, {"references":["Muller, J. & Troschel, F. H. (1842) System der Asteriden. 1. Asteriae. 2. Ophiuridae. Braunschweig, Vieweg, xxx + 134 pp., 12 pls.","Mah, C. L. (2018) New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean. Zootaxa, 4539 (1), 1 - 116. https: // doi. org / 10.11646 / zootaxa. 4539.1.1","Bo, M., Canese, S. & Bavestrello, G. (2018) On the coral-feeding habit of the sea star Peltaster placenta. Marine Biodiversity, 49, 2009 - 2012. https: // doi. org / 10.1007 / s 12526 - 018 - 0931 - 4"]}

Seriaster Jangoux, 1984 Figure 10 A���D Seriaster Jangoux, 1984: 281,284; A. M. Clark 1996: 191 Comments. Seriaster was originally described in Jangoux (1984) and tentatively assigned to the Solasteridae based on the shape of the actinal plates as compared with Rhipidaster and abactinal plates from other solasterids including Solaster regularis and Lophaster. Jangoux (1984) also pointed out affinities between Seriaster and Chaetaster. Examination of the adambulacral plates in both Seriaster and members of the Solasteridae revealed that they are distinctly different. Solasterids, using Rhipidaster as the exemplar (Fig. 3), possess a wide adambulacral plate, each separated from the other plates by a distinct tissue filled space. Seriaster, in contrast, lacks the large, wide transversely arranged adambulacral plate with the broad round facet and tissue-filled space between plates and has instead smaller more block-shape adambulacral plates present in a transverse series with each adambulacral plate facing separated by a small tissue-filled space (Fig. 10D). The adambulacral plates are abutted directly onto the adjacent inferomarginal, which in turn was in contact with the the parallel superomarginal plate. Both marginal plate series followed Blake���s (1978) definition for marginal plates in which the series tracks from the interradius to the arm terminus. Seriaster also possesses abactinal plates in ordered imbricate series forming regular papular pores sitting between paxillae-like plates, exhibit hyaline spinelets on the abactinals and lacks the abactinal skeleton structure observed in solasterids, including the reticular, irregular skeleton observed in Rhipidaster or the paxillae-like plates sitting on round, imbricate plates observed in Lophaster. Our skeletal observations disagree with the placement of Seriaster within the Solasteridae made by Jangoux (1984) and are more consistent with placement within the Hyalinothricinae., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 93, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Jangoux, M. (1984) Les asterides littoraux de Nouvelle-Caledonie. Bulletin du Museum national d'Histoire naturelle, Series 4, 6 A (Zoologie, Biologie et Ecologie animale), 2, 279 - 293.","Blake, D. B. (1978) The taxonomic position of the modern sea-star Cistina Gray, 1840. Proceedings of the Biological Society of Washington, 91 (1), 234 - 241."]}

Rhipidaster vannipes Sladen, 1889 Figure 4 A���E Rhipidaster vannipes Sladen, 1889: 448. Rhipidaster (Xenorias) polyctenius Fisher, 1913: 222. Xenorias polyctenius: Fisher 1919: 451. Comments. Examination of additional specimens in comparison with the the descriptions and type material indicates synonymy of Xenorias polyctenius Fisher, 1913 with Rhipidaster vannipes Sladen, 1889. Based on this synonymy and the occurrence of specimens, this species occurs between 167���503 m and occurs widely between the North and the South Pacific. Characters used to distinguish between the two taxon concepts, show poor boundaries. Body ratios for example are overlapping. The R/ r ratio for the two species were described as Rhipidaster vannipes is 3.1 to 3.23 versus R/ r= 3.5 in Xenorias polytenius. Based on new specimens, R/ r shows a range of 2.44 to 4.4 with the highest and lowest R/ r ratios observed on Japanese specimens. Furrow spines also overlap in number among individuals. Xenorias polyctenius was described as having pri- marily eight to ten furrow spines versus seven or eight in Sladen���s holotype. The Japanese specimens displayed primarily eight to ten but four up to twelve. New Caledonian specimens showed six to eight furrow spines (at R=4.1 to 4.6) Similar characters include the distinctive enlarged, broad oral plates with a smooth, bare surface surrounding the raised ���eminence��� on either side of the membrane covered fossae present in each interradius between the paired oral plates (Fig. 4D). Arrangement of the marginal and actinal plates are in identical linear series. Paxillae (also called pseudopaxillae in the literature) morphology is one of the few character differences between the two species. Paxillae in the holotype of Rhipidaster vannipes appear to be more elongate with four or five spinelets and free from a tissue sheath versus Xenorias polyctenius which have shorter, stouter paxillae, which are embedded in a tissue sheath bearing eight to twelve spinelets. However, individuals from other localities show overlap in numbers of paxillar spinelets. Japanese individuals show mostly four to eight (but as few or as many as two to ten) spinelets whereas individuals from New Caledonia show three to six spinelets per paxilla, all with relatively stout, short paxillar shafts. Spines on some of the New Caledonia specimens do show elongate spinelets in conjunction with the shaft, suggesting that this could be a variable character owing to collection artifact, flexibility of the spinelets, or simply naturally occurring variation of the individual while alive. The majority of examined specimens (n=37) from Japan and New Caledonia displayed eight rays with a minority (n=8) showing seven rays and one individual from New Caledonia showing six rays. Sladen���s holotype possessed eight rays whereas Fisher���s type for Xenorias polyctenius showed seven. Gut Content Note: Fragments from what appear to be the arms of an unidentified ophiacanthid were observed in the oral and tube foot grooves of IE-2013-12117 suggesting that the ophiuroid was being eaten. Although artificial positioning forced during trawl collection presents an alternative explanation, predation on other echinoderms would be consistent with the feeding ecology of other solasterids (e.g., Mauzey et al. 1968; Van Veldhuizen & Oakes 1981). Occurrence: East China Sea, Japan (Tosa Bay), Vanuatu, New Caledonia, Molucca Islands, Torres Strait, 167��� 503 m. Description. Body stellate, arms seven or eight, interradial arcs acute. Arms thick, round in cross section. Body surface covered with thick membrane (Fig. 4A). Abactinal surface forms close-set fenestrate skeleton composed of irregularly cylindrical plates arranged in a reticulate network framed around a thick membrane covering over each papular region each of one to four papulae present. Papular regions proximally with greater number of papulae with regions narrowing, decreasing to single papulae forming more close-set spaces which eventually terminate distally. Papulae present on all surfaces but absent from large distinct regions extending from abactinal to actinal surface. Reticulate skeleton covered by distinct membrane, which extends as a covering over abactinal spinelets, two to ten, mostly four to eight forming tufts on plate surfaces, especially where plates abut (Figs. 4B, C). Underlying paxillar base is low and round in outline. Madreporite with weakly convex to flat surface on raised plate above disk surface. Marginal plates, 60 to 70 from arm tip to arm tip, form paired series along lateral side with a membrane-covered intermarginal region along the distance of the arm (Fig. 4C). Both superomarginals and inferomarginals with membrane covered, webbed spinelets, two to seven, mostly four to six in palmate curved sequence. Short membrane covered spinelets, two to four present on intermarginal surface. Superomarginal and inferomarginals arranged serially at oblique angles from one another on most, but with some, especially distal plates arranged in parallel, directly below the inferomarginals. Adambulacral plates with four to 12 webbed, palmate, furrow spines, mostly eight to 10 on each plate, a discrete distance separates the furrow spines from two to four subambulacral spines in palmate arrangement (Fig. 4E). Actinal intermediate regions covered by membrane but with no other accessories other than one to four small spinelets. Oral plates with 12���14 membrane-covered spinelets; surface smooth and membrane covered. Oral plate surface enlarged, smooth, with no accessories (Fig. 4D). Oral plate convexities paired and covered by membrane and six to eight ensacculate spines with one enlarged spine and three to five smaller spine per side. The enlarged spine is paired its other oral plate counterpart, totaling two projecting into the moth. Preserved specimens show mottled coloration. Material Examined (longest arm measured). Japan. NSMT E-11341, East China Sea, 29˚0.57���N, 127˚0.40���E��� 28˚58.71���N, 126˚59.55���E, 167���170 m, Coll. R / V Yoko-maru, St. 13 - T13, 19 October 2001, 1 wet spec., R =1.6 r=0.5, 7 arms; NSMT E-11342, Tosa Bay, 33˚13���N, 133˚37.4���E���33˚12.6���N, 133˚36.8���E, 290���293 m, Coll. R / V Kotaka-maru, St. K00-8-300, 24 August 2000, 1 wet spec., R =3.0 r=0.8, 8 arms; NSMT E-11343, Tosa Bay, 33˚13.2���N, 133˚36.9���E���33˚10.33���N, 133˚36.2���E, Coll. R / V Kotaka-maru, St. K98-6-250, 8 June 1998, 1 wet spec., R =36 r=10, 8 arms; NSMT E-11344, Tosa Bay, 33˚10.6���N, 133˚34.4���E���33˚10.3���N, 133˚33.9���E, 300���302 m, Coll. R / V Kotaka-maru, St. K97-11-300, 14 November 1997, 1 wet spec., R =3.2 r=0.8, 8 arms; NSMT E-11345, Tosa Bay, ca. 300 m, Coll. R / V Kotaka-maru, 1 wet spec., R =3.8 r=1.1, 8 arms; NSMT E-11346, Tosa Bay, 33˚13.7���N, 133˚35.9���E���33˚13.4���N, 133˚35.4���E, 177���179 m, Coll. R / V Kotaka-maru, St. K97-5-175, 14 May 1997, 3 wet specs, R =2.3 R =0.7, 7 arms, R =2.9 R =1.0, 8 arms, R =4.2 r=1.2, 8 arms; NSMT E-11347, Tosa Bay, 33˚14.0���N, 133˚38.3���E��� 33˚13.6���N, 133˚38.0���E, 261���273 m, Coll. R / V Kotaka-maru, St. K99-3-250, 5 March 1999, 5 wet specs., R =4.02 r=1.3, 8 arms, R =3.7 r=1.0, 8 arms, R =3.6 r=0.9, 8 arms, R =4.3 r=1.2 8 arms, R =4.8 r=1.3, 7 arms; NSMT E- 11348, Tosa Bay., 33˚12.2���N, 133˚35.4���E���33˚11.8���N, 133˚35.1���E, 252���267 m, Coll. R / V Kotaka-maru, St. K97-5- 250, 16 May 1997, 2 wet specs, R =3.5 r=0.8, 8 arms, R =2.9 r=0.7, 8 arms; NSMT E-11349, Tosa Bay, 33˚13.7���N, 133˚37.3���E���33˚13.2���N, 133˚37���E, 239���258 m, Coll. R / V Kotaka-maru, St. K98-12-250, 9 December 1998, 5 wet specs, R =3.9 r=1.2, 8 arms, R =3.0 r=0.9, 8 arms, R =3.2 r=1.0, 8 arms, R =3.2 r=0.9, 8 arms, R =2.2 r=0.5, 8 arms; NSMT E-11350, Tosa Bay, 33˚14.4���N, 133˚37.5���E���33˚14.1���N, 133˚36.9���E, 198��� 191 m, Coll. R / V Kotaka-maru, St. K98-6-200, 8 June 1998, 5 wet specs, R =2.2 r=0.9, 8 arms, R =3.6 r=1.3, 8 arms, R =3.6 r=1.1, 8 arms, R =3.6 r=1.1, 8 arms, R =3.8 r=1.1, 8 arms; NSMT E-11351, Tosa Bay, 33˚10.2���N, 133˚31.8���E���33˚9.7���N, 133˚31.4���E, 202���209 m, Coll. R / V Kotaka-maru, St. K97-8-200, 20 August 1997, 1 wet spec., R =4.6 r=1.3, 8 arms; NSMT E-11352, Tosa Bay, 33˚13.1���N, 133˚36.6���E���33˚12.7���N, 133˚36.2���E, 245���248 m, Coll. R / V Kotaka-maru, St. K98-1-250, 25 January 1998, 3 wet specs, R =3.6 r=1.0, 8 arms, R =3.6 r=0.9, 8 arms, R =3.1 r=0.9, 8 arms. NSMT E-11353, Tosa Bay, 33˚13.6���N, 133˚36.4���E���33˚13.3���N, 133˚35.8���E, 198���200 m, Coll. R / V Kotaka-maru, St. K97-11-200, 14 November 1997, 6 wet specs all with 8 arms, R =1.6 r=0.5, R =1.7 r=0.5, R =1.7 r=0.4, R =2.8 r=0.9, R =4.0 r=1.4, R =3.7 r=1.3; NSMT E-11354, Tosa Bay, 33˚13.4���N, 133˚36.0���E���33˚13.1���N, 133˚35.5���E, 196���198 m, Coll. R / V Kotaka-maru, St. K97-5-200, 16 May 1997, 1 wet spec., R =4,2 r=1.3, 8 arms; NSMT E-11355, Tosa Bay, 33˚13.6���N, 133˚36.4���E���33˚13.3���N, 133˚35.8���E, 198���200 m, Coll. R / V Kotaka-maru, St. K97-11-200, 14 November 1997, 1 wet spec., R =3.2 r=1.0, 8 arms; NSMT E-11356, Oomurodashi Volcano, South of Izu-oshima Island, Japan, 34˚28.0���N, 139˚31.3���E���34˚28.3���N, 139˚31.6���E, 223���234 m, Coll. R / V Tansei-maru, KT-87-19, St. OM-3, 10 December 1987, 2 wet specs, R =5.3 r=1.5, 8 arms, R =4.3 r=1.0, 7 arms. New Caledonia. IE-2007-1691, New Caledonia, 18��57���S, 163��16���E, 460 m, Coll. P. Bouchet aboard N/O Alis, CONCALIS St. CP 2957, 2 dry specs., both with 7 arms, R =4.6 r=1.1,, R =4.1 r=1.3; IE-2013-12117, New Caledonia, 18��54���72���, 163��23���73���, 452��� 420 m, Coll. BATHUS 4, CP 928, 7 Aug 1994, 1 wet spec., R =6.5 r=1.8, 6 arms; IE-2013-5702 Grand Passage, New Caledonia, 19�� 4��� 30.0036��� S; 163�� 30��� 18.018��� E, 225���230 m, Coll. SMIB 6 dr. 110, 2 March 1990, 2 wet specs., R =3.0 r=1.0, 7 arms, R =1.2 r=0.3, 8 arms; IE-2007-1728, Grand Passage, New Caledonia, 18�� 58��� 6.6��� S; 163�� 14��� 54.0132��� E, 432���448 m, Coll. CONCALIS CP 2958, 1 wet spec., 7 arms, R =1.9 r=0.5. Vanuatu. IE-2013-12848, N Malekula, Vanuatu, 15�� 50��� 17.3976��� S; 167�� 17��� 28.8096��� E, 207���280 m, Coll. N /O Alis, 5 October 1994, 4 dry specs., 7 arms, R =1.7 r=0.5, R =1.4 r=0.3, R =0.8 r=0.2, R =0.7 r=0.2; IE-2013-8345, N Malekula, Vanuatu, 15�� 50��� 17.3976��� S; 167�� 17��� 28.8096��� E, 207���280 m, Coll. N /O Alis 5 October 1994, 2 dry specs. Arafura Sea. NHM 90.5.7.706, Holotype, Between Cape York and Frederick Henry Island, 51.2 m (28 fms) HMS Challenger St. 188, Coll. 10 September 1874, 1 wet specimen R =8.5 r=2.7., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on pages 77-80, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Sladen, W. P. (1889) Report on the Asteroidea. Report on the Scientific Results of the Voyage of H. M. S. Challenger during the years 1873 - 1876, Zoology, 30 (51), xlii + 893 pages, 118 plates.","Fisher, W. K. (1913) New starfishes from the Philippine Islands, Celebes, and the Moluccas. Proceedings of the United States National Museum, 46, 201 - 224. https: // doi. org / 10.5479 / si. 00963801.46 - 2022.201","Fisher, W. K. (1919) Starfishes of the Philippine seas and adjacent waters. Bulletin of the US National Museum, 3 (1000), 1 - 547. https: // doi. org / 10.1126 / science. 50.1293.348","Mauzey, K. P., Birkeland, C. & Dayton, P. K. (1968) Feeding behavior of asteroids and escape responses of their prey in the Puget Sound region. Ecology, 49, 603 - 619. https: // doi. org / 10.2307 / 1935526"]}

Hyalinothrix enoki n. sp. Figure 6 A���D Etymology: The species epithet, enoki refers to a specific type of Japanese mushroom which bears a similar appearance to the clavate paxillar spines observed in this species. Noun held in apposition. Diagnosis. Hyalinothrix species distinguished by paxillae bearing non-glassine, spinelets with clavate or macelike tips. Comments. This species possesses non-glassine, clavate shaped spinelets present on the abactinal and body surface, which makes it the most morphologically divergent of Hyalinothrix species relative to the type species, Hyalinothrix millespina as described by Fisher (1911), which possess glassine spinelets on its abactinal and other body surface paxillae. Occurrence: Izu Islands, Japan, 160��� 171 m. Description. Body stellate (R/r=3.5���3.6), arms round in cross-section, interradial arcs acute (Fig. 6A). Abactinal surface composed of cruciform-shaped basal plates each with four rounded imbricating lobes forming fenestrate network. Lobes short, each of four plates forming the boundary for papular region, each region most spread out proximally becoming more tightly arranged distally on arm.Abactinal plates arranged in distinctly linear, widely spaced rows along arms. Linear rows most complete along arm, becoming incomplete proximally along arm, more irregular on disk. Single papular pores regularly along body surface, larger proximally but becoming absent distally as those distalmost plates become most closely articulated. Each plate with cruciform-shaped base, tip with a tuft of blunt, non-glassine spines with clavate tips, four to 30, mostly five to 20 (Fig. 6B). Superomarginal and inferomarginal series track from interradial region to arm terminus (sensu Blake 1978). Spinelets finger-like rather than clavate on abactinal plates. Marginal plates otherwise similar to abactinals, with cruciform base, papular pores absent between marginal rows. Actinal plates present on disk and midway along arm, each with two to 20, mostly four to 10 blunt, finger-like (non-clavate) spines (Fig. 6C, D). Papular pores absent. Adambulacral plates crescentic, with curve facing distally (Fig. 6D). Each plate with three to 10 blunt, fingerlike spines, mostly three to eight, present in pairs along each plate with two facing into the tube foot furrow. Each adambulacral plate separated by tissue from the next. Oral plates, each with 10 finger-like spines, totaling 20 per interradius. Papular pores absent from actinal field. Color in life was white. Material Examined. Holotype. NSMT E-7115A, Northeast of Hachijyo-jima Island, Izu Islands, Japan, R / V Shin���yo-maru St. 29, 33˚31.5���N, 140˚15.5���E���33˚31.3���N, 140˚15.4���E, 160���161 m, 23 October 2003, 1 wet spec., R =1.4 r=0.4. Paratypes: Japan, NSMT-E-7115B, Northeast of Hachijyo-jima Island, Izu Islands, R / V Shin���yo-maru St. 29, 33˚31.5���N, 140˚15.5���E���33˚31.3���N, 140˚15.4���E, 160���161 m, 23 October 2003, 1 wet spec., R =0.6 r=0.2. NSMT E- 7149, Northeast of Hachijyo-jima Island, Izu Islands, R / V Shin���yo-maru St. 29, 33˚32.9���N, 140˚16.0���E���33˚32.8���N, 140˚15.9���E, 170���171 m, 23 October 2003, 1 wet spec., R =1.8 r=0.5. Hyalinothrix sp. cf. gracilis Aziz & Jangoux, 1985 Figure 7 A���D Comments. The specimen described herein appears in accord with the description of Hyalinothrix gracilis as outlined by Aziz & Jangoux (1985) differing in having a less stellate body form (R/r=4.75���5.0) versus R/r= 5.4 in in the holotype, having slightly more spinelets per paxilla (up to 50 versus 40 on the holotype), and the oral plates displaying 10 rather than seven to eight furrow spines. However, the current specimens were collected from the Izu Islands in Japanese waters at 160���168 meter depth versus the holotype which was apparently collected from Indonesian waters at 5684 meter depth. The collection depth is drastically different not only from these specimens but other known Hyalinothrix species, which are only known to occur in Hyalinothrix are not frequently encountered and explanations for these inconsistencies include the possible that this is simply a widely occurring species, a closely related cryptic species, or simply an error in reporting of the locality. Occurrence. Izu Islands, Japan. 260��� 268 m. Description. Body strongly stellate (R/r=4.75���5.0), arms round in cross-section, interradial arcs acute (Fig. 7A). Abactinal surface composed of well-developed cruciform plates with stout bases, forming fenestrate network (Fig. 7B). Lobes forming around a single papular pore, most spread out proximally becoming more tightly arranged distally on arm. Abactinal plates arranged in distinctly linear widely spaced rows. Linear rows most complete along arm. Each abactinal base with a tuft of fine spinelets with jagged, hyaline tips, four to 50, mostly 20 to 40. Single, or less abundantly, double papular pores regularly along body surface, larger proximally but becoming absent distally as those distalmost plates become most closely articulated. Marginal plates similar if not identical to abactinals, but both superomarginal and inferomarginal series track from interradial region to arm terminus (sensu Blake 1978). Spinelets finger-like rather than clavate on abactinal plates.Marginal plates otherwise identical to abactinals, with cruciform basal outline, papular pores absent. Actinal region very small. (Fig. 7C) Actinal plates present on disk and midway along arm, each with two to 20, mostly four to 10 blunt, finger-like (non-clavate) spines. Papular pores absent. Adambulacral plates rectangular to weakly curved, with curve facing distally (Fig. 7D). Each plate with four to six, mostly four or five, fine, glassine furrow spines, with hyaline tips that are webbed in a weakly curved fan. Furrow spines separated from subambulacral spine cluster by a discrete open space, subambulacral area covered by 10���30, mostly 20���25 fine glassine spinelets each with one to three serrate tips (Fig. 7D). Each adambulacral plate separated by tissue from the next. Oral plates, each with 10 finger-like spines, totaling 20 per interradius. Color in life was a dark orange/brown with light yellow to tan mottling on the abactinal side. Oral side was white to cream. Material Examined. NSMT E-7101, Northeast of Hachijyojima Island, Izu Islands, Japan, 33˚31.2���N, 140˚16.6���E���33˚31.4���N, 140˚16.7���E, 166���168 m, Coll. R / V Shin���yo-maru, St. 28, 23 October 2003, 1 wet spec., R =3.5 r=0.7; NSMT E-7147, Northeast of Hachijyojima Island, Izu Islands, Japan, 33˚31.5���N, 140˚15.5���E���33˚31.3���N, 140˚15.4���,161��� 160 m, Coll. R / V Shin���yo-maru., St. 29, 23 October 2003, 1 wet spec., R =3.8 r=0.8., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on pages 86-89, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Blake, D. B. (1978) The taxonomic position of the modern sea-star Cistina Gray, 1840. Proceedings of the Biological Society of Washington, 91 (1), 234 - 241.","Aziz, A. & Jangoux, M. (1985) Four new species and one new subspecies of Asteroidea (Echinodermata) collected by the Siboga expedition in the Indo-Malayan region. Bijdragen tot de Dierkunde, 55 (2), 263 - 274. https: // doi. org / 10.1163 / 26660644 - 05502005"]}

Hyalinothrix vitrispinum n. sp. Figure 9 A���D Etymology: The species epithet is derived from the Latin vitrum for glass or glassy and spinum for spine alluding to the elongate, glassine spines present in this species. Diagnosis. A species diagnosed by the elongate glassy spinelets present on the paxillar surface, which extend to the surface of adjacent paxillae. Furrow spines six or seven. Comments. This species shares the most distinguishing characters with Hyalinothrix millespina, primarily the elongate glassine spinelets present on the abactinal and surface paxillae which extend well beyond the surface of each plate, forming an interlocking array of spinelets between the plates above the papulae and the fasciolar grooves. Subambulacral spines glassine forming thick, dense tufts proximally. This species is distinguished by the presence of six or seven furrow spines and elongate glassy spinelets on the surface paxillae, numbering mostly between 30 to 40, but exceptionally up to 60. Occurrence: Balut Island, Philippines, 150��� 250 m. Description. Body strongly stellate (R/r=6.6���7.0), arms wide at base, tapering distally. Arms cylindrical in cross-section (Fig. 9A). Abactinal plates paxillate, plates low to moderately height, forming well-defined fasicolar grooves. Plate bases flattened, lobate in shape, mostly four but some three-lobed. All have with overlapping, imbricating bases. Approximately four plates with lobes forming corners around each papular pore. Tissue covers overlapping basal plates. Each plate widening at top forming wide, broader plate surface than base; abactinal plate surface round to polygonal in outline, abactinal plate surface convex, covered with spines. Lateral edge of each plate covered by 20���60, mostly 30���40 fine, elongate glassine spines (Fig. 9B) with single or two-pronged tips forming an overlapping canopy over the fasciolar groove below it. Central plate surface covered by 20���40 shorter hyaline spines similar to those around the plate edges, widely spaced. Central surface of most plates on the holotype show signs of erosion; spination absent. Abactinal plates homogenous in shape, with more polygonal to oval shaped plates occurring proximally and rounder plates occurring more distally. Plates larger proximally becoming smaller distally. Radial series are irregular, carinal series indistinct but lateral arm plates form distinct transverse series along the adradial to lateral arm surfaces. Madreporite strongly convex with distinct sulci, but obscured by glassine spines forming canopy on adjacent paxillar plates. No pedicellariae. Marginal plates, approximately 120���130 per interradius (at R=5.4) versus 45���50 at R=3.5, individual plates indistinct from those on abactinal surface with identical spine types and numbers. Recognition of marginals follows positional criterion of Blake (1976) and were tracked from the terminal plate, alongside the adambulacrals along the arms, then interradially. Actinal plates present in two series in weakly chevron-like pattern, restricted to disk with none extending along the arm (Fig. 9D). Actinal paxillae are continuous in series with those on abactinal and lateral surface, identical in appearance with consistent numbers of glassine abactinal spines. Furrow spines blunt, six or seven, mostly six, per plate in weakly palmate series with smallest spines at ends and tallest spines present centrally on fan (Fig. 9D). Furrow spines five in six-armed paratype (CASIZ 229110). Smallest spines are at least Material Examined. Holotype: NMEC 6916, Balut Island, Philippines, 150���250 m, 1 dry spec., R =5.4 r=0.8. Paratypes: CASIZ 229109, Balut Island, Philippines, 150���250 m, 1 dry spec., R =3.5 r=0.5. CASIZ 185670, Aliguay, Mindanao, Philippines, spec., 100���200 m, 1 dry spec R =4.6 r=0.6. 6-armed: CASIZ 229110 Balut Island, Philippines, 150���250 m, 1 dry spec., R =4.1 r=0.6, taken from longest arm, 6 arms, uneven lengths). Mah PH06, Balut Island, Philippines, 200 m, PH06, 1 dry spec., R =5.3 r=0.8 (one arm bifurcated)., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on pages 90-93, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847

Paralophaster Fisher, 1940 Paralophaster Fisher, 1940: 175; A. M. Clark 1962: 52; McKnight 2006: 10. Myoraster Fisher, 1940: 181. Comments. Paralophaster as outlined by Fisher (1940) are five-rayed solasterids diagnosed based on superomarginals which are largely identical with other abactinal paxillae and have abactinal paxillae arranged in oblique transverse rows. Lophaster has enlarged and widely separated superomarginal paxillae without paxillae in transverse rows. Based on Mah and Foltz (2011) Paralophaster was supported as the sister taxon to the clade including Lophast- er as the sister to a branch containing Solaster and Crossaster (Fig. 1), suggesting the multi-armed condition was derived relative to a plesiomorphic five rayed condition. Paralophaster contains four species, three of which occur primarily in Antarctic settings with one species, Paralophaster hyalinus H. E. S. Clark, 1970 from New Zealand. This species represents the first occurrence of Paralophaster outside of the Southern Hemisphere., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 75, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Fisher, W. K. (1940) Asteroidea. Discovery Reports, 20, 69 - 306.","Clark, A. M. (1962) Asteroidea. B. A. N. Z. Antarctic Research Expedition 1929 - 1931, B 9, 68 - 70.","McKnight, D. G. (2006) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea- stars). 3. Orders Velatida, Spinulosida, Forcipulatida, Brisingida with addenda to Paxillosida, Valvatida. NIWA Biodiversity Memoir, 120, 1 - 187.","Mah, C. L. & Foltz, D. W. (2011) Molecular Phylogeny of the Valvatacea (Asteroidea, Echinodermata). Zoological Journal of the Linnean Society, 161, 769 - 788. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00659. x","Clark, H. E. S. (1970) A new species of Paralophaster (Asteroidea) from New Zealand. Transactions of the Royal Society of New Zealand, Biological Sciences, 12, 177 - 179, pl. 1."]}

Hyalinothrix Fisher, 1911 Hyalinothrix Fisher, 1911: 659; McKnight in Clark & McKnight 2001: 152 (in key), 153. Comments. Hyalinothrix was first described from deep-water settings in the Hawaiian Island region. It is broadly known only from tropical, deep-water settings in the North, Central and South Pacific. No species are known from the Atlantic or Indian oceans. Hyalinothrix, as summarized herein includes six species. Five species, H. millespina, H. diversus n. sp., H. grangei, H. gracilis, and H. vitrispinum n. sp. show the glassy paxillar spinelets as outlined by Fisher (1911) in his description of Hyalinothrix millespina. This is in contrast to Hyalinothrix enoki n. sp., which displays shorter, blunt, opaque spinelets, suggesting a more intermediate morphology with other Asterinidae., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 83, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270 pp."]}

Rhipidaster Sladen, 1889 Rhipidaster Sladen, 1889: 447. Rhipidaster (Xenorias) Fisher, 1913: 222. Xenorias Fisher, 1919: 451. Comments. It is argued herein that Xenorias Fisher, 1913 is a junior synonym of Rhipidaster Sladen, 1889. Fisher (1913, 1919) differentiated Xenorias from Rhipidaster based on the position of the marginal plates, which he argued formed oblique rather than parallel chevrons (in Rhipidaster) with one another, touching by the inter marginal ends along the side of the ray. Re-examination of these plates on dry specimens showed that the superomarginal and inferomarginal plates were in contact with articulated ends intermarginally permitting flexure. Thus, both parallel and oblique marginal plate arrangements are possible, in many cases on the same arm of a single individual. Although Rhipidaster was not included in the most phylogenetic revision of the Valvatacea (Mah & Foltz 2011), the possession of multiple arms suggests greatest affinity with Solaster or Crossaster (Fig. 1)., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 77, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Sladen, W. P. (1889) Report on the Asteroidea. Report on the Scientific Results of the Voyage of H. M. S. Challenger during the years 1873 - 1876, Zoology, 30 (51), xlii + 893 pages, 118 plates.","Fisher, W. K. (1913) New starfishes from the Philippine Islands, Celebes, and the Moluccas. Proceedings of the United States National Museum, 46, 201 - 224. https: // doi. org / 10.5479 / si. 00963801.46 - 2022.201","Fisher, W. K. (1919) Starfishes of the Philippine seas and adjacent waters. Bulletin of the US National Museum, 3 (1000), 1 - 547. https: // doi. org / 10.1126 / science. 50.1293.348","Mah, C. L. & Foltz, D. W. (2011) Molecular Phylogeny of the Valvatacea (Asteroidea, Echinodermata). Zoological Journal of the Linnean Society, 161, 769 - 788. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00659. x"]}

SOLASTERIDAE Viguier 1878 Multi-armed solasterid genera such as Crossaster and Solaster occupy important ecological roles as predators (see Mauzey et al. 1968; Carlson & Pfister 1999; among others) and display importance in influencing community structure (e.g., Himmelman & Dutil 1991). Some five-rayed solasterids, such as those in the genus Lophaster are also predators (e.g., Duncan & Sladen 1889; Mah pers. obs.) but are not as well understood. Solasterids include a total of 52 species in ten genera, which occur primarily in cold to temperate water habitats ranging from intertidal to abyssal (> 3000 m) depths. The Solasteridae includes nine living genera in addition to the Jurassic Brachisolaster. Fisher (1911) provided one of the last comprehensive keys to the genera within the Solasteridae. In the Japanese region, initial accounts of Japanese solasterids included those of Sladen (1889) and Fisher (1911). Hayashi (1939, 1940) provided comprehensive descriptions and identification keys to Solaster and Crossaster species from Japanese waters. Hayashi (1973) described a new species, Lophaster asiaticus, which was also the first account of Lophaster from Japanese waters. Imaoka et al. (1991) was the first to identify Lophaster furcilliger Fisher, 1905, a species previously known from the Pacific coast of North America and the Aleutians, from the Japan Sea. More recently Kogure & Kaneko (2010) described Seriaster regularis from Okinawa and provided a key to Japanese solasterids (in Japanese). Comprehensive molecular phylogenetic treatments of the Solasteridae have not yet been undertaken, but both the two- and three-gene trees in Mah & Foltz (2011) support five-rayed forms, such as Lophaster and Paralophaster, as relatively relative to multi-rayed forms such as the more derived Crossaster and Solaster. Although the position of the ���traditional��� Ganeriidae (sensu Spencer & Wright 1966) is not completely understood, its position on proximal locations on the broader clade are relevant to the Solasteridae as potential sister taxa given shared synapomorphies between some ganeriids and basal solasterids. Diagnosis. Body stellate, disk thick, well defined arms, 5 to 15, round in cross-section. Abactinal surface composed of lobate plates in irregular reticulum, displaying variably close to wide articulation with single to large papular expression. Plates with variable accessories ranging from spines to paxillae. Marginal plates present in two series (following Blake 1978), but one or both series show variable degrees of expression resembling abactinal plates or paxillae. Actinal plates restricted to disk in most taxa. Adambulacral plates wing-like, forming transverse series with interadambulacdral plate spaces filled with tissue. Adambulacral plate surface with variable spine expression projecting into furrow. Subambulacral spination variably expressed as individual spines, in tufts or as combs., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 69, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Mauzey, K. P., Birkeland, C. & Dayton, P. K. (1968) Feeding behavior of asteroids and escape responses of their prey in the Puget Sound region. Ecology, 49, 603 - 619. https: // doi. org / 10.2307 / 1935526","Carlson, H. R. & Pfister, C. A. (1999) A seventeen-year study of the rose star Crossaster papposus population in a coastal bay in southeast Alaska. Marine Biology, Berlin, 133, 223 - 230. https: // doi. org / 10.1007 / s 002270050461","Sladen, W. P. (1889) Report on the Asteroidea. Report on the Scientific Results of the Voyage of H. M. S. Challenger during the years 1873 - 1876, Zoology, 30 (51), xlii + 893 pages, 118 plates.","Hayashi, R. (1939) Solasterids in Japanese waters. Journal of the Faculty of Imperial Science of Hokkaido University, 6 (3), 297 - 311.","Hayashi, R. (1940) Contributions to the Classification of the sea-stars of Japan. I. Spinulosa. Journal of the Faculty of Imperial Science of Hokkaido University, 6 (7), 107 - 204.","Kogure, Y. & Kaneko, A. (2010) A solasterid asteroid Seriaster regularis (Echinodermata, Asteroidea, Velatida) found in the Okinawa Islands: The first record from Japanese waters. Bulletin of the Biogeographical Society of Japan, 65, 97 - 102. [in Japanese]","Mah, C. L. & Foltz, D. W. (2011) Molecular Phylogeny of the Valvatacea (Asteroidea, Echinodermata). Zoological Journal of the Linnean Society, 161, 769 - 788. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00659. x","Spencer, W. K. & Wright, C. W. (1966) Asterozoans, Part U: Echinodermata In: Moore, R. C (Ed.), Treatise on Invertebrate Paleontology, University of Kansas Press, Lawrence, 3 (1), U 4 - U 107.","Blake, D. B. (1978) The taxonomic position of the modern sea-star Cistina Gray, 1840. Proceedings of the Biological Society of Washington, 91 (1), 234 - 241."]}

Hyalinothrix diversus n. sp. Figure 5 A���F Etymology: The species epithet is derived from the Latin diversus for different or separate alluding to the many differently shaped abactinal paxillae present on the disk. Diagnosis. A stellate species (R/r=5.4 to 6.5) with tapering arms, thick disk and flat oral surface. Variably shaped abactinal paxillae, especially on the disk, with 10���60, mostly 20���40 glassine spinelets abactinal spinelets, each with multispinous glassine tips. Marginal plates similar to abactinal plates, each bearing 40���60 densely packed spinelets. Actinal plates each with 8���15 short, papillate spinelets. Furrow spines 4 to 6 in palmate arrangement. Subambulacrals, 5 to 9, blunt, elongate in a single transverse series, set off from furrow spines by discrete space. Second subambulacral spine cluster with 10-15 blunt spines. Comments. Although this species displays paxillae, its thick disk and arms and relatively flattened actinal surface suggest a comparison with the asterinid Nepanthia. This species is similar to Hyalinothrix grangei nov. comb., in that several of its characters suggest intermediate morphology between Hyalinotrix and Nepanthia. Structures, such as the ���paxillae��� in Hyalinothrix and the ���subpaxillar��� plates in asterinids such as Paranepanthia grandis (see O���Loughlin & Waters 2004: fig. 5c) show distinction mainly based on elongation of the plate above the base. Occurrence: Balut Island, Philippines, 150��� 250 m. Description. Body strongly stellate (R/r=5.4 to 6.5), arms tapering, forming isosceles trapezoid in cross-section, oral surface flat, disk thick (Fig. 5A). Abactinal plate arrangement forming distinct round papular pores between paxillar plates. Individual plates ovate to quadrilobate, imbricate distally forming more fenestrate skeleton proximally (Fig. 5B). Well developed fasciolar grooves present. Plates with paxillar spines and raised ridges, both forming fasciolar grooves between them, but individual plates highly varied in shape. Disk plates vary in outline from round, trigonal, quadrate to polygonal. Plates on arm primarily oval to round to quadrate or polygonal in shape becoming more homogeneous distally. Short, glassine spinelets, 10���60, mostly 20���40, equal to or shorter to the length of paxillae densely to evenly distributed, present on each disk-radial region plate (Fig 5C). Abactinal paxillae broadly separated into a disk and central radial region and a lateral-interradial on disk region. Disk-radial abactinal paxillae in irregular series individual paxillae are heterogeneous in shape and size, with some smaller plates 25% of the size of other larger plates. Five primary disk plates present at the apex of each interradius, each about three times the size of adjacent smaller paxillae. Lateral plate fields begin interradially from the primary plates on the disk, forming linear, transverse series extending from the contact with the radial/disk plate field to the superomarginal plate series. These lateral arm plate fields are round to polygonal in outline with rounder, smaller plates present adjacent to the superomarginal series. Lateral fields include multiple series proximally decreasing to a single series distally, running parallel to the superomarginals. Papulae irregular but present on both radial and lateral fields, more abundant proximally, becoming less so distally and finally disappearing near armtip. Madreporite, weakly convex to flat, obscured by three or four adjacent paxillae, with well-developed sulci. Marginal plates, approximately 120���130 per interradius (60���65 per arm), plates are paxillar, identical to those on adjacent ���lateral��� plate field, oval to polygonal in shape topped by 40���60 sharp densely packed spinelets (Fig. 5E). Superomarginals show 1:1 association with inferomarginals. Well-developed fasciolar grooves present between marginal plate series. Actinal plates in three or four series on disk, one or two series present proximally on arms, pinching out basally. Actinal plates papillate with eight to 15 blunt, short spinelets; fasciolar grooves well-developed. Furrow spines blunt, four to six, mostly four or five (at R=3.0 to 4.0) in palmate arrangement, with proximal most spines shortest relative to the longer medial to distal furrow spines (Fig. 5F). Largest individual (R=7.4) with five spines on most proximal adambulacral plates, six on distalmost plates. Furrow spines are set deeply into tube foot furrow. Subambulacrals blunt, elongate, five to nine, mostly five to seven, variably in a single transverse series, or a cluster set off from furrow spines by a discrete space. A second subambulacral spine cluster, including 10���15 blunt spines is adjacent to the actinal plate contact and more closely resembles an actinal paxillar plate. Oral plate furrow spines seven (at R=~4.0), eight or nine at R=7.0, forming fully convex curve around edge of oral plate projecting into mouth. Oral plate surface with two low plates bearing three spines each on each plate totaling six per plate, 12 per interradius. Material Examined. Holotype: NMEC 6915, PH-05 Balut Island, 150���250 m, 1 dry spec., R =4.6 r=0.8 Paratypes: CASIZ 229107, PH-01 Balut Island, 150���250 m, 1 dry spec., R =6.5 r=1.4, CASIZ 229108, PH-01 Balut Island, 150���250 m, 2 dry specs, R =3.9 r=0.6, R =3.8 r=0.7., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on pages 84-86, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["O'Loughlin, P. M. & Waters J. W. (2004) A molecular and morphological revision of genera of Asterinidae (Echinodermata: Asteroidea). Memoirs of Museum Victoria, 61 (1), 1 - 40. https: // doi. org / 10.24199 / j. mmv. 2004.61.1"]}

Lophaster asiaticus Hayashi, 1973 Lophaster asiaticus Hayashi, 1973a: 9; 1973b: 87 Diagnosis. A species of Lophaster distinguished by four or five long furrow spines, four serrate subambulacral spines and abactinal paxillae with 13 to 19 spinelets. Comments. This was the first Lophaster species described from Japan. So, far it has only been described from the Sagami Bay region, including the Uraga Channel and nearby areas. Little is known regarding this species. Jimi et al. (2017) reported presence of the myzostomid endoparasite Asteriomyzostomum from Mie, Japan. Occurrence. Sagami Bay region, including Uraga Channel and off Chiba, Japan, 200��� 400 m. Material Examined. Holotype. NSMT-Ast R: 98. Amadaiba, Sagami Bay, Japan, 200 m, Coll. 21 July 1956, 1 wet spec., R =3.7 r=1.0. Other material: NSMT E-7155, off Iwai, Uraga Channel, Japan, ca. 200���400 m, Coll. Chogoro-maru 15 April 2004, 1 wet spec., R =3.4 r=0.6; NSMT E-7158 off Miura Peninsula, Sagami Bay, Japan, 35˚13.45���N, 139˚32.0���E, 170���330 m, Coll. Sankyo-maru, St. 2, 21 February 2001, 1 wet spec., R =5.8 r=1.9; NSMT E-7189, off Iwai, Chiba Prefecture, Japan, 200���300 m, Coll. Chogoro-maru, 15 April 2004, 1 wet spec., R =6.1 r=2.0; NSMT E-7190, off Iwai, Chiba Prefecture, Japan, 100���200 m, Coll. Chogoro-maru, 4 October 2004, 1 wet spec., R =6.1 r=2.0; NSMT E-7183, SW of Suno-saki, Chiba, Japan 34��55.5���N 139��40.2���E to 34��55.4���N 139��40.5���E, 375��� 275 m, Coll. R / V Shin���yo-maru, St. 9, 18 October 2003, R = 3.1 r=0.6., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 71, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Hayashi, R. (1973 a) Seven new species of asteroids from Sagami Bay. Journal of the College of Liberal Arts, Toyama University. Natural. Sciences, 5, 1 - 13.","Hayashi, R. (1973 b) The Sea-Stars of Sagami Bay. Biological Laboratory, Imperial Household, Tokyo, 114 pp., 18 pls.","Jimi, N., Moritaki, T. & Kajihara, H. (2017) Rare endoparasitic Asteriomyzostomum (Annelida: Asteriomyzostomidae) from Japan, including three new species descriptions and their phylogenetic position within Myzostomida. Parasitology International, 66 (6), 841 - 847. https: // doi. org / 10.1016 / j. parint. 2017.08.001"]}

Lophaster cactorum n. sp. Figure 2 A���E Etymology: The species epithet is derived from the Latin cactus, the prickly plant, alluding to the many furrow spines and the high number of paxillar spinelets. Diagnosis. A stellate to strongly stellate species (R/r=2.7���4.7), arms round, strap-like in outline, interradial arcs moderate. Actinal surface flattened. Abactinal paxillae with 6���50, mostly 20���40 fine glassine spinelets, each with 2���4, fine hyaline tips. Approximately 40 paxillar marginal plates per interradius (arm tip to arm tip), enlarged relative to the adjacent abactinal paxillae. Each marginal with a tuft of 10���30, mostly 15���20 spinelets with 1���2 fine glassine tips. Actinal plates primarily on disk, extending partially along arms. Actinals each covered with small hyaline spinelets with fine tips. Furrow spines, 5 to 9 (mostly 7 or 8), webbed, decreasing from 9 to 5 proximal to distal. Subambulacrals 3 or 4, with serrated edges. Comments. Lophaster cactorum n. sp. is distinguished from other species in having seven to nine furrow spi- nes per adambulacral plate (at R=2.8���3.0) (Fig. 2E), which is the highest number of furrow spines known for the Japanese species. Other Lophaster species possess fewer furrow spines (n=2 to 6 for comparable R of 2.8 to 3.0). This species also displays a large number of fine paxillar spinelets (20���40) relative to other Japanese species. Occurrence: Southwestern Japan, 293���1181 m Description. Body stellate to strongly stellate (R/r=2.7���4.7), arms round, weakly convex in cross-section, strap-like in outline. Interradial arcs moderate. Actinal surface flattened (Fig. 2A). Abactinal skeleton reticulate composed of paxillar plates (Fig. 2B) with three lobate processes emerging from the base, articulating with adjacent paxillae. These create open network covered with an opaque membrane, through which one to four large papulae emerge. More distal plates, less reticulate becoming more flattened and imbricate. Papulae are most abundant proximally on the disk bearing up to four (R up to 3.0) but decreasing to single papulae proximally on the arms, then disappearing completely on the distal half of the arms. A prominent interradial region on the disk is devoid of papulae but not of paxillae and is composed of denser skeleton with fewer open regions. These interradial areas are directly associated with large, primary, paxillar plates on the disk (Fig. 2C). Paxillae widely spaced, each with six to 50, mostly 20���40 fine, glassine spinelets with two to four fine hyaline tips. Madreporite polygonal, convex sitting on the apex of the bare interradial region adjacent to one of the primary plates. No pedicellariae. Marginal plates, approximately 40 per interradius (arm tip to arm tip), both superomarginal and inferomarginal plates paxillate (Fig. 2C), each plate enlarged, approximately six to eight times the size of adjacent abactinal plate. Large cylindrical base for each plate, each paxillae with a tuft of 10���30, mostly 15���20 fine hyaline spines each with single or two point glassine tips. Superomarginals and inferomarginals with one to one correspondence but with each plate directed away from the other (Fig. 2C); distinct gap between the two, shape round in outline. Inferomarginal plate with a larger, thicker tuft of fine hyaline spines, 10 to 50, mostly 20 to 40, almost quadrate in outline. No intermarginal papulae present between marginals. Both superomarginal and inferomarginal paxillae widely spaced from one another. Surface between marginal paxillae is smooth and barren of accessories. Paired marginal plates in contact at the center of the interradius. Actinal plates round, bulbous, arranged in widely spaced, ordered chevron-like series (Figs. 2D, E), extending from disk approximately 70% of the arm distance before ���pinching out.��� Each plate covered by small, hyaline spinelets each with one or two glassine tips, numbering 10 to 40, mostly 20 to 30, alternating with subambulacrals on each adambulacral plate. Well developed fasciolar channels between plates. Adambulacral plates separated by tissue between plate contacts. Furrow spines webbed, five to nine, but mostly seven or eight, with nine spines proximally decreasing to five distally (Fig. 2E). Furrow spines form convex fan-like array with webbing present over 50% of the distance between spines. Subambulacral spines, three or four, mostly three with serrated edges, all centered adjacent to the furrow spine on each adambulacral plate. Oral plate with 12 webbed furrow spines, identical to those on adambulacral plates and one spine per oral plate directed into the mouth (thus, two total per interradius). Oral plates, strongly convex with one to four small round spiny round plates similar to those on the actinal surface covered by micro-spination, total cover numbering up to 15 spinelets. Tube feet well-developed, groove is wide. Color of living specimens shows it to be a dark brown with white marginal paxillae. Material Examined. Holotype. NSMT E-11325, Off Cape Toi-misaki, Miyazaki Prefecture, Japan, 31˚07.9284���N, 131˚39.0357���E, 31˚06.6968���N, 131˚39.0302���E, 1063���1082 m, Coll. R / V Tansei-maru, KT-11-12, St. T10-2, 23 June 2011, 1 wet spec., R =3.1 r=0.8. Paratypes. NSMT E-11326, Off Cape Daio-saki, Wakayama Prefecture, Japan, 34˚05.9���N, 136˚40.8���E��� 34˚05.9���N, 136˚38.7���E, 422���425 m, Coll. R / V Tansei maru, KT-86-6, St. KN 4, 27 May1986, 1 wet spec., R =4.8 r=1.2; NSMT E-11327, Off Tanabe, Wakayama Prefecture, Japan, 33˚35.49���N, 135˚10.33���E���33˚35.44���N, 135˚08.00���E, 322���346 m, Coll. R / V Tansei-maru, KT-84-12, St. 27, 2 September 1984, 1 wet spec., R =2.9 r=0.8; NSMT E- 11328, Tosa Bay, Japan, 33˚10.8���N, 133˚38.1���E���33˚10.4���N, 133˚36.9���E, 408���413 m, Coll. R / V Kotaka-maru, K98- 6-400, 29 June 1998, 1 wet spec., R =2.8 r=0.9; NSMT E-11329, Tosa Bay, Japan, 33˚12.5���N, 133˚38.6���E���33˚12.2���N, 133˚38���E, 364���382 m, Coll. R / V Kotaka-maru, K99-9-400, 27 September 1999, 1 wet spec., R =2.6 r=0.8; NSMT E-11330, West of Heda, Suruga Bay, Japan, 34˚46.64���N, 138˚41.86���E���34˚47.17���N, 138˚40.86���E, 349���542 m, Coll. R / V Seisui-maru, CT 95-4, St. CT4, 5 October 1995, 1 wet spec., R =4.3 r=0.9; NSMT E-11331, East of Cape Taitosaki, Boso Peninsula, Japan, 35˚05.225���N, 140˚51.8357���E to 35˚04.273���N,140˚ 50.876���E, 971���1011 m, Coll. R / V Tansei-maru, KT-03-17, St. TS 6-5, 18 November 2003, 4 wet specs., R =2.8 r=0.8, R =2.7 r=0.1, R =2.9 r=0.9, R =2.6 r=1.3; NSMT E-11332, West of Matsuzaki, Suruga Bay, Japan, 34˚46.7���N, 138˚41.4���E���34˚47.7���N, 138˚42.7���E, 405��� 457 m, Coll. R / V Tansei-maru, KT-79-11, St. OT-4, 19 July 1979, 1 wet spec., R =3.7 r=1.0; NSMT E-11333, Tosa Bay, Japan, 33˚11.982���N, 133˚37.936���E���33˚12.356���N, 133˚38.124���E, 370���380 m, Coll. R / V Kotaka-maru, K98-9- 400(2), 8 September 1998, 1 wet spec., R =1.5 r=0.4; NSMT E-11334, Southeast of Tokachi, Hokkaido Prefecture, Japan, 42˚15.84���N, 144˚05.24���E���42˚16.53���N, 144˚05.68���E, 992���1042 m, Coll. KT-90-8, St. KR 09, 14 June 1990, 1 wet spec., R =3.5 r=0.8; NSMT E-11335, 32˚32.9���N, 132˚27.2���E���32˚33.0���N, 132˚29.7���E, 1090���1091 m, Coll. R / V Tansei-Maru, KT-86-16, St. C, 2 November 1986, 3 wet specs., R =2.7 r=0.8,, R =2.1 r=0.5,, R =4.6 r=1.4; NSMT E-11336, Kumano Sea, 33˚54.556���N, 136˚50.292���E���33˚55.279���N, 136˚49.391���E, 1165���1181 m, Coll. R / V Tansei- Maru, KT-88-15, St. KN 17, 21 August 1988, 1 wet spec., R =3.3 r=1.2; NSMT E-11337, South of Tanegashima Island, Kagoshima Prefecture, Japan, 29˚58.99���N, 130˚57.13���E���29˚59.41���N, 130˚58.59���E, 993���1031 m, Coll. R / V Tansei Maru, KT-97-2, St. YT-6(2), 17 February 1992, 1 wet spec., R =3.3 r=0.8; NSMT E-11338, Tosa Bay, Japan, 33˚12.3���N, 133˚36.5���E���33˚12.6���N, 133˚37���E, 293���300 m, Coll. R / V Kotaka-maru, K97-5-300, 16 May 1997, 1 wet spec., R =1.9 r=0.5, 6 arms. NSMT E-11339, Tosa Bay, Japan, 33˚13.2���N, 133˚40.1���E���33˚13.6���N, 133˚40.6���E, 397 m, Coll. R / V Kotakamaru, K 00-5-400, 9 May 2000, 1 wet spec., R =3.0 r=0.8., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on pages 71-73, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847

Hyalinothrix grangei (Clark & McKnight, 2001) nov. comb. Nepanthia grangei H. E. S. Clark & McKnight 2001: 159. Comments. A review of diagnostic characters of Hyalinothrix versus comparable taxa in the Asterinidae indicate that Nepanthia grangei Clark & McKnight, 2001 should be re-assigned to the genus Hyalinothrix. Holotype images and the description of Nepanthia grangei showed the specimen with abactinal paxillar plates, described as tabulate, with glassine spinelets, which are absent from the definition of Nepanthia (e.g., Rowe & Marsh 1982; O���Loughlin & Waters 2004) and nearly all asterinids, which display spines sitting directly on abactinal and other low-lying surface plates. Nepanthia grangei was placed into Pseudonepanthia by O���Loughlin & Waters (2004), but comparisons of the type species, Pseudonepanthia gotoi A. H. Clark 1916 show spines sitting directly on the abactinal plates (O���Loughlin & Waters 2004), rather than on elongate tabulate or paxillar plates, as indicated on Nepanthia grangei. If Nepanthia grangei is re-assigned to Hyalinothrix, this has an significant outcome on the interpretation of molecular phylogenetic results presented in Mah & Foltz (2011). In their trees (Mah & Foltz 2011: Fig. 2), Nepanthia grangei occurs on a well supported branch (93%) with Tarachaster australis and implies a sister group relationship between Nepanthia and the ���paxillate ganeriids��� such as Tarachaster. This taxonomic change would support Hyalinothrix and Tarachaster on a single, relatively well-supported branch, separate from Chaetaster, which was supported as sister branch to the Odontasteridae. Hyalinothrix and Tarachaster on a single branch would separate them from the Ganeriidae sensu Spencer and Wright (1966) and Fisher (1911), which included Cycethra, Perknaster, and Cuenotaster, disputing the historical interpretation of the Ganeriidae as monophyletic., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 89, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270 pp.","O'Loughlin, P. M. & Waters J. W. (2004) A molecular and morphological revision of genera of Asterinidae (Echinodermata: Asteroidea). Memoirs of Museum Victoria, 61 (1), 1 - 40. https: // doi. org / 10.24199 / j. mmv. 2004.61.1","Mah, C. L. & Foltz, D. W. (2011) Molecular Phylogeny of the Valvatacea (Asteroidea, Echinodermata). Zoological Journal of the Linnean Society, 161, 769 - 788. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00659. x","Spencer, W. K. & Wright, C. W. (1966) Asterozoans, Part U: Echinodermata In: Moore, R. C (Ed.), Treatise on Invertebrate Paleontology, University of Kansas Press, Lawrence, 3 (1), U 4 - U 107."]}

Lophaster Verrill, 1878 Lophaster Verrill, 1878: 214; Sladen 1889: 458; Ludwig 1900: 467; Fisher 1911: 334; Koehler 1920: 143; Djakonov 1950: 63; H. E. S. Clark 1963: 61; Bernasconi 1964: 258; Clark & Downey 1992: 299; McKnight 2006: 9. Sarkaster Ludwig, 1905: 185. Comments. With the description herein, Lophaster includes eleven species occurring worldwide in cold to temperate settings. The description of Lophaster cactorum n. sp. brings the total number of Pacific species up to four, including L. asiaticus, L. furcilliger, and L. suluensis. Another four species, L. densus, L. gaini, L. stellans, and L. tennis, are recorded from Antarctic and high-latitude waters. Lophaster furcifer is recorded from the Arctic and North Atlantic, Lophaster verrilli from Puerto Rico and Lophaster quadrispinus is recorded from South Africa, Japanese solasterids were reviewed by Hayashi (1939) with the first Lophaster record documented by Hayashi (1973) who reported L. asiaticus from Sagami Bay with subsequent records of L. furcilliger in Japan by Oguro in Imaoka et al. (1990) and in Korea by Lee & Shin (2009). Although they have yet to be documented, it seems likely that the other two species, L. asiaticus and L. furcilliger will be reported from nearby localities as further areas have been sampled. Lophaster spp. generally show diagnostic features largely tied to specific numbers of abactinal spinelets, furrow spines and other variable characters. Several species within Lophaster, such as L. furcilliger and L. furcifer show relatively few morphological differences suggesting to some (e.g., Grieg 1932; Mortensen 1932) that they represent a single, widely occurring species. Molecular data has shown both extremes, including multiple forms as part of a widely occurring species, such as Hippasteria phrygiana (Foltz et al., 2013) and cryptic species, showing similarity but differentiated by very few morphological characters, as seen in the Asterinidae (e.g., O���Loughlin & Waters 2004)., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on pages 70-71, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Verrill, A. E. (1878). Art. XX. Notice of recent additions to the marine fauna of the eastern coast of North America. No. 1. American Journal of Science and Arts. 3 (16), 207 - 215.","Sladen, W. P. (1889) Report on the Asteroidea. Report on the Scientific Results of the Voyage of H. M. S. Challenger during the years 1873 - 1876, Zoology, 30 (51), xlii + 893 pages, 118 plates.","Ludwig, H. (1900). Arktische Seesterne. Fauna Arctica. 1 (3), 447 - 502.","Koehler, R. (1920). Echinodermata: Asteroidea. Scientific Reports of the Australasian Antarctic Expedition C 8, 1 - 308.","Djakonov, A. M. [1950 (1968)] Morskie Zvezdy Morei SSSR T U 34, 1 - 203. [Translated as Dyakonov. A. M. 1968. Sea stars (Asteroids) of the USSR Seas. Keys to the Fauna of the USSR 34. Zoological Institute of the Academy of Sciences of the USSR, ed. By Strelkov, A. A., Israel Program for scientific translations Ltd. Jerusalem, 183 pp.]","Bernasconi I. (1964) Asteroideos argentinos. Claves para los ordenes, familias, subfamilies y generos. Physis, 24, 241 - 277.","McKnight, D. G. (2006) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea- stars). 3. Orders Velatida, Spinulosida, Forcipulatida, Brisingida with addenda to Paxillosida, Valvatida. NIWA Biodiversity Memoir, 120, 1 - 187.","Ludwig, H. (1905) Asteroidea. Memoirs of the Museum of Comparative Zoology at Harvard, 32, 1 - 292.","Hayashi, R. (1939) Solasterids in Japanese waters. Journal of the Faculty of Imperial Science of Hokkaido University, 6 (3), 297 - 311.","Lee, T-J. & Shin, S. (2009) A Newly Recorded Sea Star of the Genus Lophaster (Asteroidea: Velatida) from Korea. Animal Systematics, Evolution and Diversity, 25 (3), 331 - 333. https: // doi. org / 10.5635 / KJSZ. 2009.25.3.331","Mah, C. L. & Foltz, D. W. (2011) Molecular Phylogeny of the Valvatacea (Asteroidea, Echinodermata). Zoological Journal of the Linnean Society, 161, 769 - 788. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00659. x","Grieg, J. A. (1932) Echinodermata. Report on the Scientific Results of the \" Michael Sars \" North Atlantic Deep-sea Expedition 1910. 3 (2): 1 - 47, 5 pls. 10 figs.","Mortensen, T. (1932). The Godthaab Expedition 1928 Echinoderms. Meddelelser om Gronland. 79 (2), 1 - 62, 1 plate.","Foltz, D., Fatland, S., Eleaume, M., Markello, K., Howell, K., Neil, K. & Mah C. (2013) Global population divergence of the sea star Hippasteria phrygiana corresponds to onset of the last glacial period of the Pleistocene. Marine Biology, 160 (5), 1285 - 1296. https: // doi. org / 0.1007 / s 00227 - 013 - 2180 - 1","O'Loughlin, P. M. & Waters J. W. (2004) A molecular and morphological revision of genera of Asterinidae (Echinodermata: Asteroidea). Memoirs of Museum Victoria, 61 (1), 1 - 40. https: // doi. org / 10.24199 / j. mmv. 2004.61.1"]}

Ganeriinae Sladen, 1889 Diagnosis. Abactinal plates, bearing spinelets in most taxa, primarily imbricate to reticulate, plates embedded within membrane or overlain by soft tissue. Marginal plates variably quadrate to flattened and imbricate. Paxillate in Cuenotaster. Actinal plates imbricate, embedded in tissue or abutted, but arranged in chevron-like pattern. Type genus is indicated by *. Included Taxa: Aleutiaster A.H. Clark 1939, Cuenotaster Thi��ry in Koehler, 1920, Cycethra Bell, 1881, * Ganeria Gray, 1847, Perknaster Sladen, 1889, Scotiaster Koehler, 1907, and Vemaster Bernasconi, 1965. Comments. The Ganeriidae were originally described as a subfamily within the Asterinidae (Sladen 1889) but was later separated and elevated to family status by Fisher (1911). Fisher (1919) proceeded to include Hyalinothrix within the Ganeriidae, which was morphologically distinct from the more typological ganeriids, such as Ganeria and Cycethra as outlined by Sladen (1889). Ganeriidae are poorly studied outside of Antarctica. Some genera, such as Perknaster have been studied for their ecological roles (e.g., McClintock et al. 2000), but most non-Antarctic taxa (e.g., Hyalinothrix) are known primarily from taxonomic literature (e.g., Fisher 1911). The Ganeriidae within the Asterinidae. Recent molecular work in asteroid phylogeny has revealed relatively close phylogenetic relationships between the Asterinidae, the Ganeriidae, and more distantly the Solasteridae (Mah & Foltz 2011; Matsubara et al. 2004). Work by Mah & Foltz (2011) suggests a polyphyletic Ganeriidae with clades nestled within the greater clade containing the Asterinidae. The ganeriids, such as Cycethra Bell, 1881 and Perknaster Sladen, 1889, which more closely resemble the type genus Ganeria Gray 1847 form with Cuenotaster, a distinct clade from the more ���paxillate ganeriids��� such as Tarachaster which is also included in the Asterinidae but on a separate clade. Nepanthia grangei McKnight, 2001, which was reconstructed as the sister clade to Tarachaster tenuis Fisher 1913, was likely misclassified and is best assigned to Hyalinothrix. This group, including Tarachaster and Hyalinothrix is herein designated the Hyalinothricinae, following a prior hypothesis of similarity discussed by Fisher (1911)., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 81, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Sladen, W. P. (1889) Report on the Asteroidea. Report on the Scientific Results of the Voyage of H. M. S. Challenger during the years 1873 - 1876, Zoology, 30 (51), xlii + 893 pages, 118 plates.","Clark, A. H. (1939). A new genus of starfishes from the Aleutian Islands. Proceedings of the United States National Museum 86 (3061), 497 - 500","Koehler, R. (1920). Echinodermata: Asteroidea. Scientific Reports of the Australasian Antarctic Expedition C 8, 1 - 308.","Bell, F. J. (1881). Account of the Echinodermata collected during the Survey of H. M. S. \" Alert \" in the Straits of Magellan and on the Coast of Patagonia. Proceedings of the Zoological Society of London. p. 87 - 101, p. VIII & IX.","Gray, J. E. (1847). Descriptions of some new genera and species of Asteriadae. Proceedings of the Zoological Society of London. 72 - 83.,","Bernasconi, I. (1965). Nuevo genero y nueva especie abisal de Goniasteridae (Echinodermata, Asteroidea). Physis. 25 (70), 333 - 335.","Fisher, W. K. (1919) Starfishes of the Philippine seas and adjacent waters. Bulletin of the US National Museum, 3 (1000), 1 - 547. https: // doi. org / 10.1126 / science. 50.1293.348","McClintock, J. B., Baker, B. J., Amsler, C. D. & Barlow, B. L. (2000) Chemotactic tube-foot responses of the spongivorous sea star Perknaster fuscus to organic extracts of sponges from McMurdo Sound, Antarctica. Antarctic Science, 12 (1), 41 - 46. https: // doi. org / 10.1017 / S 0954102000000067","Mah, C. L. & Foltz, D. W. (2011) Molecular Phylogeny of the Valvatacea (Asteroidea, Echinodermata). Zoological Journal of the Linnean Society, 161, 769 - 788. https: // doi. org / 10.1111 / j. 1096 - 3642.2010.00659. x","Matsubara, M., Komatsu, M. & Wada, H. (2004) Close relationship between Asterina and Solasteridae (Asteroidea) supported by both nuclear and mitochondrial gene molecular phylogenies. Zoological Science, 21, 785 - 793. https: // doi. org / 10.2108 / zsj. 21.785","Fisher, W. K. (1913) New starfishes from the Philippine Islands, Celebes, and the Moluccas. Proceedings of the United States National Museum, 46, 201 - 224. https: // doi. org / 10.5479 / si. 00963801.46 - 2022.201"]}

Lophaster furcilliger Fisher, 1905 Lophaster furcilliger Fisher, 1905: 312; 1911: 334; Djakonov 1950: 64; Alton 1966: 1706; Oguro in Imaoka et al. 1991: 91; Kogure & Hayashi 1998: Lambert 2000: 79; Lamb & Hamby 2005: 329; Lee & Shin 2009: 331. Lophaster furcilliger vexator Fisher, 1910: 574; Fisher 1911: 334; Djakonov 1968: 55. Lophaster furcilliger vaxator (sic): Baranova 1957: 163. Sarkaster validus Ludwig, 1905: 185. Diagnosis. Lophaster displaying two to five (mostly four or five) furrow spines, up to 20 spinelets per paxillae. Large size with specimens up to R=9.2. Comments. Lophaster furcilliger is a widely occurring species along the Pacific coast of North America, extending from the Galapagos to Japan and Korea. This species was first recorded from the Sea of Japan by Oguro in Imaoka et al. (1991) with subsequent occurrence in the Sado Strait recorded by Kogure and Hayashi (1998). Based on the relatively few spinelets on each paxillar spine, the elongate arms and the bathymetric range, species observed herein are most consistent with the type species Lophaster furcilliger rather than the ���shallow water��� subspecies L. furcilliger vexator. Fisher (1910,1911) designated this subspecies, L. furcilliger vexator based on larger disk, thicker rays, (and thus smaller R/r), stouter abactinal and marginal paxillae, each with six to ten fine points instead of two to four, heavier adambulacral spines and more closely placed adambulacral plates. Baranova (1957) and Djakonov (1968) regard L. furcilliger vexator as a forma of L. furcilliger and intermediate in form between the Pacific L. furcilliger and the Arctic/Atlantic L. furcifer. Fisher���s (1911: 340) account of this species refers to it as being present in ���lesser depths��� with distribution from the southern Bering Sea to northern California. Lambert (2000) and Lamb & Hanby (2005) have both indicated L. furcilliger vexator as the ���shallow-water��� subspecies. However, details as to the extent or specific occurrence are vague. Based on the case presented in the literature, L. furcilliger vexator ���s character differences are best interpreted as phenotypic variation. However, some characters such as ���thicker rays��� and ���closely placed adambulacrals��� could result from post-mortem deformation, such as in Ceramaster which shows a swollen abactinal surface in situ versus those in preserved specimens (Mah 2015). Occurrence: Japan (Sagami Bay, Sea of Japan), Korea, Bering Sea, Okhotsk Sea, Aleutian Islands, California to Baja California and Galapagos region, 86 to 4200 m. Material Examined. Japan. NSMT E-11363, Off Iwaki, Fukushima Prefecture, Japan, 37˚26.65���N, 142˚18.10���E��� 37˚27.32���N, 142˚18.59���E, 840���866 m, Coll. R / V Soyo-maru, St. 8, 2 August 2012, 1 wet spec., R =10.9 r=2.8; NSMT E-11340, Off Iwaki, Fukushima Prefecture, 37˚35.0���N, 142˚23.4���E���37˚37���N, 142˚23.4���E, 901���923 m, Coll. R / V Soyo-maru, St. C5-B, 21 July 2008. 9 wet spec., R =7.5 r=2.2, R =4.6 r=0.9, R =9.6 r=2.5, R =9.2 r=2.4, R =6.4 r=2.0, R =6.5 r=1.6, R =3.0 r=4.0, R =2.3 r=0.6, R =2.4 r=0.4; NSMT E-11311, Off Soma, Fukushima Prefecture, 37˚59.21���N, 142˚33.00���E, 1165 m, Coll. R / V Soyo-maru, St. 10, 19 July 2012, 1 spec., R =5.2 r=1.0; NSMT E-11305, Off Soma, Fukushima Prefecture, 37˚59.21���N, 142˚33.00���E, 1165 m, Coll. R / V Soyo-maru, (probably) St. 10, 19 July 2012, 9 spec., R =7.5 r=1.7, R =7.0 r=0.9, R =5.9 r=1.2, R =3.7 r=0.9, R =4.0 r=0.9, R =4.2 r=0.6, R =5.8 r=1.2, Two specimens with all arms damaged., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 73, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Djakonov, A. M. [1950 (1968)] Morskie Zvezdy Morei SSSR T U 34, 1 - 203. [Translated as Dyakonov. A. M. 1968. Sea stars (Asteroids) of the USSR Seas. Keys to the Fauna of the USSR 34. Zoological Institute of the Academy of Sciences of the USSR, ed. By Strelkov, A. A., Israel Program for scientific translations Ltd. Jerusalem, 183 pp.]","Alton, M. (1966) Bathymetric distribution of sea stars (Asteroidea) off the Northern Oregon coast. Journal of the Fisheries Research Board of Canada, 23 (11), 1673 - 1714.","Kogure, Y. & Hayashi, I. (1998) Bathymetric distribution pattern of echinoderms in the Sado Strait, the Japan Sea. Bulletin of the Japan Sea National Fisheries Research Institute, 48, 1 - 16.","Lambert, P. (2000) Sea Stars of British Columbia, Southeast Alaska, and Puget Sound. Royal British Columbia Museum Handbook. University of British Columbia Press, Vancouver, BC, 186 pp. https: // doi. org / 10.1017 / s 0025315400040194","Lee, T-J. & Shin, S. (2009) A Newly Recorded Sea Star of the Genus Lophaster (Asteroidea: Velatida) from Korea. Animal Systematics, Evolution and Diversity, 25 (3), 331 - 333. https: // doi. org / 10.5635 / KJSZ. 2009.25.3.331","Fisher, W. K. (1910) New starfishes from the North Pacific. Zoologischer Anzeiger, 35, 568 - 574.","Baranova, Z. I. (1957) Echinoderms of the Bering Sea. Issledovaniya Dalny-Vostok Morei USSR, 4, 149 - 266. [In Russian]","Ludwig, H. (1905) Asteroidea. Memoirs of the Museum of Comparative Zoology at Harvard, 32, 1 - 292.","Lamb, A. & Hanby, B. P. (2005) Marine life of the Pacific Northwest, A photographic encyclopedia of invertebrates, seaweeds and selected fishes. Harbour Publishing, British Columbia, 398 pp."]}

What is Knightaster? Based on the description outlined for Knightaster bakeri by H. E. S. Clark (1972) and H. E. S. Clark & McKnight (2001) and compared with details summarized by O���Loughlin & Waters (2004), several relevant characters suggest its membership should be ascribed to the Asterinidae. Clark (1972) proposed affinities with several ganeriid genera, such as Cycethra, but provided no characters for these relationships. Based on Clark���s (1972) description, Knightaster lacks paxillae, which are present in the other Hyalinothricinae, and has a surface with flattened, spine-bearing abactinal plates arranged into an irregular reticulum rather than imbricate plates forming a series of single regular papular pore openings. Knightaster displays several character similarities asterinids which are narrow at the base of the arm, elongate and sub cylindrical in cross-section, such as Nepanthia or Pseudonepanthia. Considering the complexity of the asterinids, it is beyond the scope of this study to further reconcile Knightaster without evaluation and comparison within the Asterinidae., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 83, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Clark, H. E. S. (1972) Knightster, a new genus of asteroid from Northern New Zealand. Journal of the Royal Society of New Zealand, 2 (2), 147 - 150. https: // doi. org / 10.1080 / 03036758.1972.10429370","Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270 pp.","O'Loughlin, P. M. & Waters J. W. (2004) A molecular and morphological revision of genera of Asterinidae (Echinodermata: Asteroidea). Memoirs of Museum Victoria, 61 (1), 1 - 40. https: // doi. org / 10.24199 / j. mmv. 2004.61.1"]}

Hyalinothrix millespina Fisher, 1911a Fisher, 1911a: 661; Mah 1998: 67 (checklist) Figure 8 A���E Comments. This species is only known from the type locality in the Hawaiian Islands and has not been encountered since its original description by Fisher (1911a). Diagnosis. A stellate species (R/r=4.5), with abactinal plates, round to polygonal in outline displaying 75���100 clear, fine spinelets on each abactinal spine tip, forming an almost fuzzy outline (Figs. 8A, B). Papulae one or two to a papular region. Marginal plates slightly larger than adjacent abactinals (Fig. 8C). Three or four series of actinal intermediate plates, becoming single series distally. Individual actinal plates, identical to those on abactinal surface, displaying 40���70 spinelets on each spine tip. Furrow spines three to five (mostly four) in a straight series (Figs 8 D���E). Remainder of adambulacral plates with a brush-like array of 10���20 short subambulacral spinelets. Occurrence: Known only from Hawaiian Islands (Maui), 232��� 282 m. Material Examined: USNM 27674 Honolua Bay, Pailolo Channel, Maui, Hawaiian Islands, 21��05���45���N, 156��40���50���W, 232���282 m, Coll. USFC Albatross, 1 wet spec., R =4.7 r=1.0., Published as part of Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, pp. 67-100 in Zootaxa 4750 (1) on page 90, DOI: 10.11646/zootaxa.4750.1.4, http://zenodo.org/record/3702847, {"references":["Fisher, W. K. (1911 a) Hyalinothrix, a new genus of starfishes from the Hawaiian Islands. Proceedings of the United States National Museum, 39, 659 - 664. https: // doi. org / 10.5479 / si. 00963801.39 - 1807.659","Mah, C. (1998) New Records, Taxonomic Notes and a Checklist of Hawaiian Starfish. Bishop Museum Occasional Papers, 55, 65 - 71."]}

Plinthaster Verrill, 1899 Verrill 1899: 161; Fisher 1906: 1052 [as Tosia section B (Plinthaster)] Verrill 1899: 166; Fisher 1911: 165 (as Pyrenaster) Fisher 1910: 172; 1911: 165; Halpern 1970a: 131; Halpern 1970b: 244; McKnight 1973: 185; Downey in Clark & Downey 1992: 259; H.E.S. Clark in Clark & McKnight 2006: 110 (as Plinthaster) Diagnosis. Body weakly stellate to pentagonal. Abactinal plates, flat, bare central surface, polygonal, no surficial granulation but with crystalline nodules/tubercles or radiating patterns present on subsurface. Marginal plates relatively few per interradius, with widely spaced coarse granules but otherwise smooth or bare. Actinal surface covered by granules. Comments. Plinthaster along with Astroceramus and Sibogaster are among several Goniasteridae which display crystalline nodules embedded in the abactinal plate surface and which also possess bald, smooth abactinal plates with few to no granules on the marginal surface. These differ from others, such as Stellaster and various members of the Ferdininae, such as Kanakaster which display crystalline nodules in conjunction with a granulated tegument covering the surface. Based on historical definitions from the literature (e.g Doderlein, 1924), Plinthaster, Astroceramus and Sibogaster have shown relatively distinct morphological boundaries, but examination of further diversity within each suggests overlap between them. Smaller sized (R=5.0) Sibogaster, for example superficially resemble very stellate Plinthaster [e.g. ��� Eugoniaster ephemeralis ��� in Macan (1938)]. Similarly, pentagonal shaped or small-sized Astroceramus can also superficially resemble Plinthaster. Plinthaster dentatus, which occurs widely in the Atlantic and possibly in the south Pacific is morphologically varied leading to a wide synonymy. A comprehensive survey of Indo-Pacific Plinthaster has never been undertaken but it seems likely, based on unpublished observations, that there is considerable, if not greater variation among Pacific species. What are Plinthaster (ex. Pentagonaster) d��derleini, P. investigatoris and P. cuenoti ?. Koehler (1910) described three Indian Ocean species of Pentagonaster, which have found current assignment to Plinthaster including Plinthaster ephemeralis, Plinthaster investigatoris, Plinthaster d��derleini and Plinthaster cuenoti. Plinthaster ephemeralis was found to be a synonym of Sibogaster digitatus D��derlein 1924 by Mah (2015). Evaluation of these other two species further suggests that assignment to Plinthaster is unwarranted. In both species, the number of marginal plates (~25���34) per interradius is high and exceeds the number present in any of the known Plinthaster species. The abactinal plate patterns and plate morphology, as described for P. investigatoris and P. d��derleini as figured by Alcock (1893) and Koehler (1910) respectively, suggest that these species have been incorrectly assigned to Plinthaster. The description of Pentagonaster investigatori s Alcock indicates that the abactinal plates are tabulate, and are distinctly isolated from one another but with a fringe of squamous membrane clad granules flush with the general surface and with marginal plates bearing a small central, elevated patch of deciduous granules. A type specimen for this species is unavailable and is most likely lost, but based on the description, this species seems best assigned to Pillsburiaster. Other species of Pillsburiaster display the same general body shape, small, irregular abactinal plate pattern, raised granulated marginal patches and granules on the abactinal surface. The marginal plate number and furrow spine number are also more similar to other known Pillsburiaster species. Pentagonaster d��derleini ���s description in Koehler (1910) is also very compatible with placement in Pillsburiaster. Similarities are similar to those observed in P. investigatoris in terms of marginal plate number and irregular abactinal plate pattern. Pentagonaster cuenoti Koehler that Fisher (1919: 260) thought was similar to Ceramaster also displays characters, such as the abactinal plate pattern and marginal plate morphology, granulated raised marginal patch and marginal plate number that are most compatible with Pillsburiaster. Absence of granules on the surface of the abactinal plates can be attributed to abrasion during collection or possibly variation as has been observed in collections of the Atlantic Pillsburiaster geographicus. Neither description of the above species mentions the presence of crystalline nodules in the abactinal plate surface which is a synapomorphy of Plinthaster. Also noteworthy is the extreme occurrence depth of both species, with Plinthaster d��derleini collected from 2160 m and P. investigatoris from 1380 m which is consistent with collection depths (800 to 2200 m) of accepted Pillsburiaster spp. These two species are also consistent with Ceramaster and Peltaster but descriptions of abactinal and marginal plate morphology are not as identical. A search for the types of these species in the MNHN collections was unsuccessful and it is likely that this material is lost., Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 72-73, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Verrill, A. E. (1899) Revision of certain genera and species of starfishes, with descriptions of new forms. Transactions of the Connecticut Academy of Arts and Sciences, 10 (1), 145 - 234. https: // doi. org / 10.5962 / bhl. part. 7031","Fisher, W. K. (1906) The starfishes of the Hawaiian islands. Bulletin of the United States Fish Commission, 23, 987 - 1130.","Fisher, W. K. (1911) Asteroidea of the North Pacific and adjacent waters. 1. Phanerozonia and Spinulosida. Bulletin of the US National Museum, 76, xiii + 1 - 420. https: // doi. org / 10.5479 / si. 03629236.76. i","Fisher, W. K. (1910) New genera of starfishes. Annals of the Magazine of Natural History, Series 8, 5 (26), 171 - 173. https: // doi. org / 10.1080 / 00222931008692747","Halpern, J. A. (1970) Goniasteridae (Echinodermata: Asteroidea) of the Straits of Florida. Bulletin of Marine Science, 20 (1), 193 - 286.","McKnight, D. G. (1973) Additions to the asteroid fauna of New Zealand: family Goniasteridae. New Zealand Oceanographic Institute Records, 1 (13), 171 - 195.","Clark, A. M. & Downey, M. E. (1992) Starfishes of the Atlantic. Chapman and Hall, London, 794 pp. https: // doi. org / 10.5860 / choice. 30 - 2659","McKnight, D. G. (2006) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars). 3. Orders Velatida, Spinulosida, Forcipulatida, Brisingida with addenda to Paxillosida, Valvatida. NIWA Biodiversity Memoir, 120, 1 - 187.","Doderlein, L. (1924) Die Asteriden der Siboga-Expedition. II. Pentagonasteridae. Siboga-Expedition, 46 (2), 49 - 69, pls. 14 - 19. https: // doi. org / 10.5962 / bhl. title. 11319","Macan, T. T. (1938) Asteroidea. British Museum of Natural History, John Murray Expedition 1933 - 34, Scientific Reports, IV (9), 324 - 432.","Koehler, R. (1910) An account of the shallow-water Asteroidea. Echinoderma of the Indian Museum, 6, 1 - 192. https: // doi. org / 10.5962 / bhl. title. 11614","Mah, C. L. (2015) New species, corallivory, in situ video observations and overview of the Goniasteridae (Valvatida, Asteroidea) in the Hawaiian Region. Zootaxa, 3926 (2), 211 - 228. https: // doi. org / 10.11646 / zootaxa. 3926.2.3","Fisher, W. K. (1919) Starfishes of the Philippine seas and adjacent waters. Bulletin of the United States National Museum, 3 (100), 1 - 547, 156 pls. https: // doi. org / 10.1126 / science. 50.1293.348"]}

Calliaster thompsonae H.E.S. Clark & McKnight 2001 Figure 8 A���E Clark, H.E.S. & McKnight 2001: 25 Diagnosis. Species with triangular tapering arms, abutted superomarginal plates present along the arm (Fig. 8A), wide superomarginal plates (Fig. 8C), large conical spines present on the abactinal and marginal plates (Fig. 8A, C), adambulacral plates rectangular, weakly convex actinal plates and six to seven furrow spines (Fig. 8E). Comments. This specimen represents a significant range extension for this species, which has previously only been documented from the Bay of Plenty in New Zealand (no depth noted). This first Indian Ocean occurrence differs in that the abactinal plates are more convex, abactinal spines are more conical (vs. more cylindrical in the New Zealand specimen), a greater number of superomarginals abut over the arm radius beginning at the base of each arm (rather than midway along the arm distance), each superomarginal plate shows a strong convex curvature with a more pronounced smooth, bare surface, and there are only one or two spines present on each superomarginal plate, rather than the two to three spines present in the New Zealand holotype (R= 8.3 cm). Pedicellariae were also not observed on this specimen whereas small spatulate pedicellariae were observed on the New Zealand holotype. This species bears immediate similarities with the South African Calliaster acanthodes H.L. Clark in that the abactinal surface displays a similar abactinal surface covered by prominent, conical spines. However, this species possesses abactinal plates extending to the arm tip with spineless abactinal arm plates. Marginal plates in Calliaster acanthodes are more quadrate in shape (i.e. closer length and width) and are directed laterally rather than producing a prominent abactinal facing. Actinal granulation in Calliaster acanthodes is well-developed, whereas the actinal surface in C. thompsonae is devoid of all surficial granulation, including granules. Occurrence. Bay of Plenty, New Zealand to Northeast coast of Somalia, 75���175 m. Description. Body stout, stellate (R/r=2.6) in outline, arms elongate, disk arched, interradial arcs broadly curved. Abactinal plates abutted, plate surfaces flat to weakly convex. Individual plates round to polygonal in outline, mostly homogenous in size, shape. Minority of plates small (about 25% of the size of a majority sized plate). Abactinal plates restricted to disk only, none beyond basal arm region. Carinal plates ranging from round (proximally) to oval (distally) in shape. Fasciolar grooves present, developed channels present around plates, six papulae present around each plate, present only over radial regions. Abactinal plates each plate with a single, prominent, sharp, conical spine (Figs. 8A, B) with only a minority of plates (two to five per interradius) lacking spines. These spines, ranging in length from 1.0 to 3.0 mm project well above the abactinal surface (Fig. 8B). Those plates lacking spines located around the periphery of the abactinal plate field, adjacent to superomarginal contact. Primary circlet plates along each radial series each with enlarged sharp, conical spine approximately twice as thick and about 25% longer than other abactinal spines. Granules, eight to 50, mostly 10���40, bead-like in shape, widely spaced around periphery of each plate (Fig. 8B). Madreporite convex, with well-developed sulci, flanked by three abactinal plates. No pedicellariae. Superomarginal and inferomarginal plates eighteen per interradius (arm tip to arm tip) (Fig. 8A), these series are slightly offset, forming zig-zag contact between them. Length of each plate with approximately 20���25 beadlike, widely spaced granules, approximately 30���50 along each width. Superomarginals six, very wide (4x the length), forming prominent distinct abactinal facing border in each interradius, arms with six plates abutted over midline on arm (Fig. 8A, C). Abutted superomarginals show mostly 1:1 correspondence, but one arm with slightly offset plates showing zig-zag contact along the arm mid-radius. Superomarginal surface strongly convex with smooth surface bearing no surficial accessories (no granules, etc.). Interradial superomarginals with two prominent, conical spines directed away from one another (Fig. 8B, C), with one directed laterally and another directed abactinally. Remainder of superomarginal plates each with a single prominent conical spine, in lateral directed series. The holotype with distalmost six plates missing spines showing only remaining convex spine base. One arm damaged with strongly convex, truncated superomarginal plates. Distalmost superomarginals becoming more quadrate with more acutely convex surface. Inferomarginal plates mostly with a single lateral series of conical, pointed spines. One to three inferomarginal plates exceptionally with two spines. No other surficial accessories. Surface smooth and bare. Inferomarginals present interradially wide (about 4x the length) becoming more elongate along arms (about 3��� 4x the width). Terminal plate rhombic in shape but with broadly rounded edges, two short blunt spines. No pedicellariae on marginal surfaces. Actinal surface, plates restricted to disk, composed of two full series in chevron-like series (Fig. 8D) with approximately three to five irregularly shaped plates becoming more jumbled in series distally. Individual plate surface flat to weakly convex, quadrate to irregularly polygonal in outline. Most plates with a large, prominent cylindrical blunt spine, one per plate, each spine approximately 1���2.0 mm in length (Fig. 8D). Actinal plate surface smooth and bare, no surficial accessories (no granules, pedicellariae, etc.). Peripheral granules, five to 20, bead-like in shape, widely spaced around actinal plate periphery. Actinal plates adjacent to inferomarginals smallest and most irregular in shape, with a minority lacking spines. Furrow spines six or seven in weakly convex to straight fan (Fig. 8E). Two enlarged subambulacral spines in transverse series, comparable in size with other actinal spines, approximately 5x the width and thickness of a furrow spine. Adambulacral plate surface otherwise bare with no surficial accessories (Fig. 8E). Adambulacral plate surface flattened to weakly convex. Oral plates with six to eight furrow spines, one enlarged blunt spine per plate projecting into mouth, two prominent subambulacral oral spines identical to those on adambulacral plates. Two paired series of six to eight angular granules flanking each side of an oral sulcus where halves of the oral plate are in contact. Material Examined. USNM 1510318, off NE coast of Somalia and south of Socotra Island 11��24���N 51��35���E. 75���175m, Coll. R / V Coll. R / V Anton Bruun cruise 9, st. 463. 1 wet spec. R=4.2 r=1.6, Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 26-28, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270."]}

Stellasteropsis colubrinus Macan 1938 Figure 36 D Macan 1938: 395; Clark & Rowe 1971: 32, 48 (as Stellasteropsis colubrinus) Diagnosis. This largely follows Macan���s (1938) description and is included herein for completeness and convenience. Body strongly stellate (R/r=3.0), arms sharply triangular, tapering. Interradial arcs acute. Abactinal, marginal, actinal surfaces covered by continuous granule-invested integument. Abactinal plates abutting, polygonal in outline, no spines or tubercles present. Pedicellariae absent. Superomarginals strongly convex forming heterogeneous periphery. Distalmost four or five inferomarginal plates with tubercle on outer distal corner. Furrow spines four or five. Adambulacral plate surface covered by granules, no differentiated accessories or spines. Granules coarser than those present on actinal surface. Comments. Stellasteropsis colubrinus reported by Chao from Taiwan [1990: 410, Figs 3B, 21, 22 (in checklist)] were misidentified. Based on Chao���s images, these show the papular pore pattern and tubercles of juvenile oreasterids, most likely in the genus Pentaceraster. The strongly stellate body shape, elongate arms, absence of abactinal spines or tubercles as well as the number of furrow spines suggests that that affinities of this species lie with the more southern Stellasteropsis fouadi, especially those individuals with smaller, narrower arms. However, this species shares the more pronounced superomarginal convexity and the inferomarginal tubercles with Stellasterospsis tuberculiferus suggesting an intermediate morphology between the two species. Occurrence. Gulf of Aden, Arabian coast, 13.5-200 m, Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 93-94, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Macan, T. T. (1938) Asteroidea. British Museum of Natural History, John Murray Expedition 1933 - 34, Scientific Reports, IV (9), 324 - 432.","Clark, A. M. & Rowe, F. W. E. (1971) Monograph of Shallow-water Indo-West Pacific Echinoderms. British Museum (Natural History) Publications 690. British Museum (Natural History), London, ix + 238, 31 pls."]}

Sphaeriodiscus ganae n. sp Figure 32 A–E Etymology. This species is named for friend and colleague, Ms. Christina Gan, professor at Highline Community College in Seattle, Washington. Diagnosis. This species lacks the secondary plates present on the abactinal surface (Fig. 32B), has fewer superomarginal plates (ten instead of 12 in S. mirabilis), lacks enlarged distalmost inferomarginal plates, and has marginal plates which are wide rather than elongate. Actinal accessories and spination are similar however. Comments. Sphaeriodiscus ganae n. sp. shares the very large convex superomarginal plates with the Atlantic Sphaeriodiscus bourgeti (Perrier 1885). However, Sphaeriodiscus ganae n. sp. has ten superomarginals per interradius (R=~3.0 cm) versus only six to eight in comparably sized specimens of S. ganae n. sp.. Sphaeriodiscus ganae n. sp. also has three or four furrow spines per plate versus four or five in S. bourgeti. Superomarginal plates, especially those enlarged ones in S. ganae n. sp., display significantly wider rather than more elongate superomarginals in S. bourgeti. Otherwise, both species are similar, lacking smaller, secondary plates with similar granulation patterns on both abactinal and marginal plates surfaces. Occurrence. Walters Shoal, western Indian Ocean, 647– 712 m. Description. Body, stout, pentagonal (R/r=1.45–1.5), interradial arcs weakly curved (Fig. 32A, D). Abactinal plates polygonal, most hexagonal with some interradial plates more irregular in shape (Fig. 32B). Secondary plates absent. Surficial plates covered by homogeneous, covering of round granules, approximately four granules present along a 1.0 mm line. Granules approximately 15–90 per plate, homogeneous overall, weakly differentiated into central and peripheral series. Peripheral granules in single row, approximately seven to 25–30, central region, approximately eight to-50 with granules in some regions densely distributed becoming so abundant that boundary between plates is obscured. Radial regions displaying papular regions in conjunction with shallow fasicolar grooves. No pedicellariae observed. Madreporite quadrate to triangular, flanked by four or five plates. Superomarginals, inferomarginals ten per interradius (arm tip to arm tip) (Fig. 32A, C). Superomarginals elongate throughout, relatively narrow interradially becoming wider and significantly more swollen distally, especially penultimate to terminal plate (Fig. 32C). Central pair of superomarginals in holotype appear significantly smaller relative to distalmost three plates on holotype (IE-2013-17139) (Fig. 32A, C). Central pair on paratype are more proportional to other superomarginals but are noticeably small relative to distalmost plates. Superomarginals and inferomarginals slightly offset with zigzag contact between them. Superomarginals have strong abactinal facing, occupying approximately (0.5/2.4) 20% of the total “r” distance interradially with distalmost two pairs of superomarginals directly abutting over midline. Penultimate superomarginal plates with strongly convex surface followed by triangular to triangular plates adjacent to the terminal plate (Fig. 32C). Superomarginal plate surface covered in a dense field of granules identical to those on the abactinal surface save for a large prominent bald patch on the abactinal surface of each plate bearing scattered, round and widely-spaced granules, ranging from seven to 30. These bald regions on some plates can be 25% of the size of the largest ones observed on the plates elsewhere. Largest penultimate superomarginals with strongly convex bald areas with up to 30 widely spaced granules. Absent granules leave concave pitting on surface. Where bald areas are reduced or absent, most of superomarginal plates covered by approximately 200–500 densely arranged, round granules, consistent in size with those on abactinal plates. On those superomarginal surfaces with larger bald regions, only 50–100 granules are present surrounding bald regions which are raised above superomarginal surface. Peripheral granules, approximately 120 total, approximately 30 on the width, 40 on the length. Inferomarginal plate series mostly covered by 200–500 coarse, round granules identical to those on superomarginal plates. Bald areas irregularly present ranging from smaller patches with three widely spaced granules to large bald patches with up to 30–40 widely spaced round granules. Penultimate inferomarginals also strongly swollen with triangular plates adjacent to terminal plate. Terminal plate small, triangular. Actinal surface with four full actinal plate series in chevron formation (Fig. 32D). Individual plates ranging from quadrate to irregularly polygonal in shape. Surface almost completely covered by coarse, round granules, six to 40 per plate, consistent with those observed on the abactinal and marginal surfaces, becoming so dense that boundaries between plates are obscured. No pedicellariae observed. Furrow spines three or four per plate, thick, blunt, round-tipped, quadrate or triangular in cross-section in a straight or weakly palmate series (Fig. 32E). but with alternating furrow spine series, three on lower series and four on upper series. These variably shown in different series or in single series depending on state of specimen preservation. Three well-defined subambulacral spine rows. First subambulacral row adjacent to furrow spine composed of primarily two spines, one smaller proximal spine and one larger and thicker distal spine. Second subambulacral spine row composed of two or three angular granules (quadrate to triangular in cross section), set off from third series composed of three granules, which eventually become continuous with granules on actinal surface or “pinch out” distally along arm. Furrow spines on oral plate four, twice as thick as furrow spines on adambulacral plates, blunt tipped, quadrate in cross-section. One spine on apex of each half of oral plate, projecting into mouth, total of two on each interradial angle. Oral plates with five short, angular granules, quadrate to triangular in cross section present along the edge of sulcus dividing each oral plate and paired on each side. Material Examined. Holotype. IE-2013-17139 Southwestern Indian Ocean, Walters Shoal. 33°8’S 44° 1’E to 33°8’S 44° 2’E, 700–712 m. Coll. MD 208 (Walters Shoal) CP 4902, 7.5.17. 1 wet spec. R=3.3 r=2.2. Paratype. IE-2013-17141 Southwestern Indian Ocean, Walters Shoal. 33°8’S 44° 0’E to 33°9’S 44° 1’E, 647–672 m. Coll. MD 208 (Walters Shoal) CP 4901, 7.5.17. 1 wet spec. R=3.5 r=2.4, Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 84-85, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911

Calliaster sarahae n. sp. Figure 7 A���E Etymology. This species is named for Dr. Sarah Samadi, professor of marine biology at the Mus��um national d'Histoire naturelle, who has been instrumental in the collection of the species included herein. Diagnosis. Body strongly stellate (R/r=3.4���4.5), arms elongate, tapering, triangular in shape. Abactinal surface plates smooth, bare with large conical spines on basal carinal plates, but absent elsewhere. Overall spines relatively few. Superomarginal plates each with one or two sharp, conical spines (Figs 7B, C), abutted over midline distally with abactinal plates extending along arms over 75% of distance (Fig. 7A). Actinal surface lacking spines, plate surface covered by granules, large pedicellariae the size of the width of each plate (Fig. 7E). Furrow spines mostly eight, proximally but up to 12 distally. Comments. This species invites comparison with Calliaster thompsonae Clark and McKnight 2001, which occurs in the Indian Ocean and in the New Zealand region with which it shares a similar overall body shape with elongate, tapering arms and a distinctly visible peripheral series of strongly convex, superomarginal plates which abut over the radius along the arm. However Calliaster sarahae n. sp. differs in that it possesses eight or more furrow spines, versus the six or seven in Calliaster thompsonae, there are far fewer conical spines on the abactinal surface limited to basal carinal arm plates and the actinal plates in Calliaster sarahae n. sp. possess are spineless, and are either bare or possess pedicellariae, whereas Calliaster thompsonae displays spines on all actinal plates. This species is also similar to Calliaster chaos n. sp. from the Mascarene Islands, but differs in that it consistently shows fewer spines present on the abactinal surface relative to C. chaos n. sp., which displays an abundance of prominent spines on the disk. Calliaster sarahae n. sp. is also much more strongly stellate (R/r=3.4��� 4.5) versus C. chaos n. sp. which shows broader arms with R/r=2.79���3.02 at a comparable size (R=~9.0 cm). Abactinal plate size and shape on C. chaos n. sp. are also heterogeneous on the arms and disk relative to the homogeneous abactinal plates on Calliaster sarahae n. sp. Occurrence. Madagascar, Walters Shoal 285���635 m. Description. Body strongly stellate (R/r=3.4���4.5). Arms strongly tapering, elongate (Fig. 7A). Interradial arcs curved. Arms upturned. Abactinal plate round to oval shaped with flat, smooth surface (Figs 7A, B). Oval shaped plates most abundant along carinal and adradial series along arms with more oval shaped plates on primary circlet and proximally on disk. Smaller, more irregular shaped plates present interradially adjacent to contact with superomarginal plates. Most plate surfaces smooth, bare. Abactinal plates continue along arms between abutted superomarginals, narrowing to a single, irregular series between superomarginals. Single, large, conical sharp spines, about 1.0 cm above the abactinal surface, with swollen base present only on proximal-most carinal series on disk extending for consistently four plates in the Madagascar specimens plates along mid-radius with a prominent conical pointed spine present on the central plate of the primary circlet. These large prominent spines absent from all other abactinal plates, but other smaller, conical spines, about the width of each abactinal plate (approximately 1.0���2.0 mm) present between central and carinal plates on IE-2013-6996. A smaller individual from Walters Shoal (IE- 2013-6997), only a single spine was observed on the proximal-most basal carinal plate. Large (about 1.0 mm), paddle-shaped pedicellariae at the base of each spine and on adradials each sitting in a concave pit corresponding to the shape of each valve. Each plate with 13���30 peripheral granules, evenly distributed, quadrate in shape. Madreporite pentagonal, weakly concave with shallow sulci abutted by six round to polygonal plates. Superomarginal and inferomarginal plates 32���42 per interradius (arm-tip to arm-tip) with 1:1 correspondence proximally with more zigzag correspondence distally along arm. Superomarginals wide, swollen, forming lateral border around disk periphery. Distalmost superomarginals, variably five to 10 pairs from terminus, abutted over mid radius. Two prominent conical spines present on three to five interradial superomarginal plates directed abactinally and dorsolaterally (Figs. 7B, C). Spine number decreases to one per plate along arms running in ordered serial formation with interradial spines. Superomarginal plates otherwise smooth, with no surficial accessories (e.g., granules, etc.). Peripheral granules 70���120 (mostly 80���100) surrounding each plate. One arm on holotype with substantive etching on superomarginal and inferomarginal surface. Inferomarginal plates wide interradially but becoming more elongate (L>W) distally along arm. Inferomarginal plates with one or two prominent, conical spines decreasing to a granular tubercle on some marginal plates with surface of inferomarginal plates irregularly covered by round to pointed granules, seven to nine (Fig. 7C). Irregularly one small paddle-shaped pedicellaria has also been observed. Terminal plate broadly triangular in shape. Actinal surface composed of approximately three complete plate series in chevron formation (Fig. 7D). Each plate polygonal to quadrate in shape. One or two relatively large (1.0 mm length) paddle-shaped pedicellariae on each plate with a corresponding pit (Fig. 7E). Most pedicellariae with two valves, but exceptionally pedicellariae with three. Pedicellariae valves variable with some individuals showing smooth edges (i.e. IE-2013-6995) whereas others display jagged teeth on valves (i.e. IE-2013-6994, 6996). Pedicellariae in regular series along actinal series adjacent to adambulacral plates series. Most with a single pedicellaria per plate, but a minority of plates with two pedicellariae per plate, mostly present on proximal-most actinal plates adjacent to oral plates. Other than pedicellariae, actinal plates with round, densely packed but evenly spaced granules, 10���30 per plate surface. Furrow spines eight proximally becoming 12 distally adjacent to arm-tip in straight to weakly curved fan on each adambulacral (Fig. 7E). Spines narrow, quadrate to angular in cross-section. Paddle-shaped pedicellariae present proximally on adambulacral plate surface. Adambulacral plates each with one or two large thick spines in transverse series each with heavily etched tips. Two spines present proximally gradually decreasing to single spine on arm tip. Transverse subambulacral spines approximately four times the thickness of an individual furrow spine and approximately three to four times the length forming prominent series along oral surface. Oral furrow spines 13���15, each oral plate surface half with one large spine identical to those on subambulacrals. Remaining oral plate surface mostly bare but distal end covered by 10���20 granules. Color in life orange. Material Examined. Holotype: IE-2007-1039 Madagascar 14��50���S 47��00E, 442 m, Coll. Bouchet & Kantor MIRIKY. 1 wet spec. R=10.9, r=3.2. Paratypes: IE-2013-6994 Madagascar 12��53���3���S 48��9���4���E, 480��� 520 m. Coll. A. Crosnier 3 April 1971. P1 Chal. 2. 1 dry spec. R=8.6 r=2.2. IE-2013-6995 Madagascar 12��43���0���S 48��13���4���E, 350��� 360 m. Coll. A. Crosnier 15 April 1971. P3 Chal. 2. 1 dry spec. R=7.9 r=2.3. IE-2013-6996 Madagascar. 12��42.4���S 48��14.3���E, 285��� 295 m. Coll. A. Crosnier, 15 Sept. 1972, P3 Chalutage 42. 1 dry spec. R=7.7 r=1.9. IE- 2013-6997 Walter���s Shoal, southern Indian Ocean. 33��11���S 44��00���E, 620��� 635 m. Coll. Marion Dufresne 0 8 st. 6. CP 47. 16 March 1976. 1 dry spec. R=6.3 r=1.4, Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 22-26, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270."]}

Monachaster D��derlein, 1916 Comments. Monachaster, in addition to Goniodiscaster and Anthenea represent genera intermediate between the Oreasteridae and the Goniasteridae, and as such have been transferred between the two groups throughout their taxonomic history. Based on the abactinal-facing superomarginals, and the paired, interradial abactinal plate pattern similar to those of Stellaster and Stellasteropsis, I agree with Tortonese (1976) and Walenkamp (1990) among others who have placed Monachaster within the Goniasteridae rather than the Oreasteridae. Some characters, such as the, dense granular covering, the minimal adambulacral spination and the bald patches on the superomarginals, also suggest Monachaster shows affinities with the Ferdininae (Goniasteridae) as described by Mah (2017)., Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on page 65, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Doderlein, L. (1916) Uber die Gattung Oreaster und verwandte. Zoologische Jahrbucher, 40, 409 - 440.","Tortonese, E. (1976) Researches on the coast of Somalia. Seastars of the genus Monachaster (Echinodermata, Asteroidea). Monitore Zoologico Italiano, New Series, Supplemento VII (6), 271 - 276. https: // doi. org / 10.1080 / 03749444.1976.10736828","Walenkamp, J. H. C. (1990) Systematics and zoogeography of Asteroidea (Echinodermata) from Inhaca Island, Mozambique. Zoologische Ferhandelingen, 261, 1 - 86.","Mah, C. L. (2017) Overview of the Ferdina - like Goniasteridae (Echinodermata: Asteroidea) including a new subfamily, three new genera and fourteen new species. Zootaxa, 4271 (1), 1 - 72. https: // doi. org / 10.11646 / zootaxa. 4271.1.1"]}

Kanakaster plinthinos Mah 2017 Figure 17 C, D Mah 2017: 34 Comments. These specimen are nearly identical to the New Caledonia individuals described by Mah (2017) with the notable difference that the small bare patches present on the superomarginal plates in the type series are absent (Fig. 17C) and in having more than ten marginal plates per interradius rather than six to eight (Fig. 17C). The body shape and joined distal superomarginals are identical. These are the first recorded occurrences of this species from beyond the type locality. Occurrence. New Caledonia, Madagascar, Kenya, 140��� 350 m. Material Examined. IE-2007-4004 Madagascar. 2608���S 4539���E, 333 m, Coll. Atimo Vatae, N / O Nosy Be 11, st. DW 3553, 5 May 2010. 1 wet spec. R=1.3 r=0.6. USNM E51268 NE of Mombasa, Kenya. 242���S, 4053 E, 140 m. Coll. R / V Anton Bruun 6 Nov. 1964. 1 wet spec. R=1.9, r=0.8., Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on page 48, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Mah, C. L. (2017) Overview of the Ferdina - like Goniasteridae (Echinodermata: Asteroidea) including a new subfamily, three new genera and fourteen new species. Zootaxa, 4271 (1), 1 - 72. https: // doi. org / 10.11646 / zootaxa. 4271.1.1"]}

Astroceramus kintana n. sp. Figure 4 A���F Etymology. The species epithet kintana is the Malagasy word for ���star��� alluding to this species strongly stellate shape. Noun is held in apposition. Diagnosis. This species is distinguished by the presence of elongate abactinal plates along approximately 50% of the arm distance by abutted superomarginal plates (Fig. 4A). It possesses seven or eight furrow spines and two enlarged subambulacral spines (Fig. 4F). Comments. This species and Astroceramus eleaumei n. sp. share several characters, including the presence of abactinal plates extending well along the arm as well as elongate arm length and an overall strongly stellate body shape; the two species are found in close geographic proximity and are similar to one another in appearance. Occurrence. Northeast of Glorioso Island, west of Mayotte Island, 455���614 m Description. Body stout, strongly stellate (R/r=2.2���3.2) with elongate, tapering arms, triangular in shape. Interradial arcs broad, weakly curved to straight (Fig. 4A, D). Abactinal plates abutted forming flush pavement, each plate hexagonal to polygonal or round in outline except for those on arm. Abactinal surface continues onto approximately 50% of proximal arm distance. Individual arm plates elongate, variably triangular to irregular in shape. Abactinal plates mostly homogeneous in shape, size becoming more irregular distally adjacent to superomarginal contact. Abactinal plates largely bare and smooth save for coarse, round small tubercular granules, zero to five, mostly one to three present on the center of each plate (Fig. 4B). These granulated plates present mainly on interradial regions but can occur on arm plates. Plates with widely spaced, coarse peripheral granules, 10���30, mostly 15���25. Paddle-shaped pedicellariae with four to seven widely spaced teeth on each valve, present on a minority of abactinal plates, (Fig. 4B) mostly present interradially adjacent to the superomarginal contact, present either individually or with one or two granules present. Pedicellariae sit within a pit extending into the surface of the plate. Other than granules and pedicellariae, plate surface is bare and smooth. Abactinal plates possess numerous crystalline nodules, 10���120, mostly 30���100, widely spaced and inset into the surface of each plate (Fig. 4B). These are numerous proximally on the disk but begin to pinch out on plates distally adjacent to the superomarginal contact and along arm plates. Madreporite quadrate, flanked by four plates. Papulae present primarily along radial regions, six per plate, present at each plate angle. Marginal plates 36���38 per interradius (arm tip to arm tip), with superomarginals abutted over midline along each arm. Superomarginals offset forming zigzag contact along distal 50% of arm distance. Marginal plates quadrate in outline interradially becoming wider along the arm base and becoming more elongate distally. Distalmost superomarginals, 10���11, abutted over midline with a more prominent abactinal superomarginal facing along arm tip. Superomarginal surface covered by coarse, closely spaced, abundant granules (Fig. 4C), approximately 20���100 on dorsolateral surface with 20���60 widely present on abactinal superomarginal plate surface. Lateral surface with few to no granules. Granules present in greatest numbers interradially decreasing significantly along distal superomarginals along arm. Peripheral granules round, coarse, approximately 20 per side/ roughly 80���150 around the complete plate. Pedicellariae paddle-like, one to three present on interradial superomarginal plates, decreasing to none along arm. Superomarginal with zigzag like contact with offset plates proximally becoming more 1:1 near arm tip. Inferomarginal plate actinal surface covered by 20���100 close but widely distributed, coarse granules, including a second peripheral series of granules, approximately 20 per side, about 80���100 in total, set within the peripheral inferomarginal granules. Terminal plate triangular in shape, smooth surface. Actinal surface composed of approximately six to eight full series in chevron formation (Fig. 4D) with the remainder irregularly present distally adjacent to interradial inferomarginal contact. Actinal plates range from quadrate to irregularly round in shape with larger plates present proximally becoming smaller and more irregular distally. Actinal plates adjacent to adambulacral plates rectangular and in addition to granular cover, nearly every plate with mostly one, but exceptionally two or more, paddle-shaped pedicellariae (Fig. 4E) identical to those present on the abactinal surface, set into s pit on each plate. Pedicellariae absent from most other actinal plates but a minority of them, one to five do have pedicellariae. Actinal plate surface covered by five to 20, mostly 10���15 widely spaced coarse round to pointed granules (Fig. 4D, E). Peripheral granules number approximately seven per side, approximately four to 40 total, most showing approximately 25���30 total. Furrow spines seven or eight blunt tipped, round in cross-section in straight to weakly palmate series. Subambulacral spines two, both thickened, bullet shaped, blunt tipped, set off from furrow spines by discrete space (Fig. 4F). On proximal plates the proximal-facing subambulacral spine is generally half the size of the distal-facing subambulacral spine. This latter large subambulacral spine is easily the width of three furrow spines with a large bulbous round tip. A minority of adambulacral plates with tong-like pedicellariae between the enlarged subambulacrals and the smaller, angular granules present. Remainder of adambulacral plate surface with four to 12 angular granules, widely spaced on plate surface. Oral plate furrow spines, eight to 10, quadrate in cross section with rounded edges, on oral plate, with one enlarged blunt spine per paired plate, triangular in cross-section projecting into mouth. Oral plate Subambulacral spines four, quadrate in cross-section, blunt-tipped with round to angular edges, set off from furrow spines by a discrete space. Paired, large angular granules, eight, present on tissue covered contact between oral plates. Approximately eight to 10 angular granules, widely spaced, present on remainder of oral plate. Color in life: orange. Notes on juvenile specimen. One specimen (MNHN IE-2013-17272) with R=1.2 shows only five superomarginals abutted over the midline but with approximately seven abactinal plates extending from the disk onto the arms. Ten superomarginals present per interradius. Actinal plates were strongly convex. Furrow spines three or four. Material Examined. Holotype: IE-2013-17176. Off west coast of Mayotte Island, 12�� 47 'S, 44�� 58' E to 12�� 46 'S, 44�� 59' E, 455���460 m. Coll. DW 4844, Jan 30, 2017. 1 wet spec. R=7.7 r=2.4. Paratypes: IE-2013-17170, Northeast of Glorioso Island, 11�� 30'S, 47�� 29' E to 11�� 29 'S, 47�� 29' E, 614��� 583 m. Coll. DW 4813, 25 Jan 2017. 1 wet spec. R=6.2 r=2.7, IE-2013-17174 Northwest of Mayotte Island, 12�� 30'S, 44�� 55' E, 606��� 610 m. Coll. DW 4863 Feb. 6 2017. 1 wet spec. R=6.8 r=2.7, IE-2013-17182, Off the southeast coast of Mayotte Island, 12�� 56'S, 45�� 15' E, 474���505m, Coll. S. Samadi, DW 4865, Feb 7, 2017. 2 wet specs R=6.4 r=2.2, R=7.7 r=2.9. IE-2013-17272, Northeast of Glorioso Island, 11�� 30'S, 47�� 28' E, 219��� 224 m. Coll. DW 4808, Jan 25, 2017. R=1.2 r=0.5, Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 15-17, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911

Milteliphaster Alcock 1893 (member of Calliaster lineage) Alcock 1893: 91 (as Milteliphaster) Comments. Rowe and Gates (1995) briefly outlined several taxonomic changes for Calliaster spinosus and Calliaster regenerator and Milteliphaster; review of one of the syntypes Milteliphaster woodmason i (MNHN IE- 2014-164) indicates that these changes were unwarranted. Milteliphaster woodmasoni demonstrates elongate, rectangular shaped marginal plates with a pronounced lateral frame, forming a very small proportion of the total ���r��� distance n the disk as opposed to nearly all of the other Calliaster species, which show a more distinct abactinal facing with a more pronounced ���r��� distance. Significant differences between M. woodmasoni and Milteliphaster wanganellensis H.E.S. Clark 1982, include wide, abactinal facing superomarginals as well as differing spine occurrence patterns and a very different, stout body morphology. The diagnoses for Milteliphaster as outlined by H.E.S. Clark (1982) and Clark and McKnight (2001) appear generalized and show relatively little difference from Calliaster, making them difficult to find useful in differentiating the two genera. The two species placed in Milteliphaster, as outlined by Rowe and Gates (1995), are also not consistent with the characters present in Milteliphaster woodmasoni given the comparison of those species with the type species, M. woodmasoni., Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on page 63, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Rowe, F. W. E. & Gates, J. (1995) Echinodermata. In: Wells, A. (Ed.), Zoological Catalogue of Australia. Fol. 33. CSIRO, Melbourne, pp. 1 - 510. https: // doi. org / 10.1086 / 419606","Clark, H. E. S. (1982) A new genus and two new species of sea-stars from North of New Zealand, with notes on Rosaster species (Echinodermata: Asteroidea). National Museum of New Zealand Records, 2 (5), 35 - 42.","Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270."]}

Eknomiaster H.E.S. Clark 2001 in Clark & McKnight 2001 H.E.S. Clark 2001: 40; Mah 2007: 316. Diagnosis. Body shape pentagonal (R/r=1.47���1.55), interradial arcs weakly curved to straight. Abactinal plates, polygonal, bare, smooth with no surficial accessories. Marginal plates, blocky, smooth with no surficial accessories, enlarged with five to eight per interradius. Actinal surface covered by granules, pedicellariae of varying types. Furrow spines three to seven. Comments. As outlined by Mah (2007) this genus was supported as a member of the Pentagonaster clade, showing morphological affinities with the Pacific Pentagonaster and Tosia. This represents the first occurrence of this genus in the Indian Ocean., Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on page 32, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270.","Mah, C. L. (2007) Systematics, Phylogeny, and Historical Biogeography of the Pentagonaster clade (Asteroidea, Valvatida, Goniasteridae). Invertebrate Systematics, 21, 311 - 339. https: // doi. org / 10.1071 / IS 06049"]}

Mediaster mollis sp. nov. Figure 21 A���F Etymology. The species epithet mollis is Latin for ���soft��� alluding to the soft texture of the abactinal body wall. Diagnosis. This species is distinguished by its strongly stellate body shape (R/r=2.54���3.0), the relatively soft abactinal body wall, low tabulae, abactinal plates with dense, abundant, homogeneous-sized granulation, 15���60 per plate (Figs 21 B, C), numerous pedicellariae on the abactinal (Fig. 21B) and marginal surface, large number of superomarginals, with 10 or 11 furrow spines, adjacent to a subambulacral series of five or six spines (Fig. 21F). Comments. This species bears a superficial resemblance to Kermitaster pacificus H.E.S. Clark & McKnight 2001, in that it possesses the granulated surface and overall shape (Clark & McKnight 2001: Figs. 14, 17). Clark & McKnight (2001: 62) note the absence of the internal radiating ossicles at the base of each abactinal plate discounting assignment to Kermitaster. This species��� generalized appearance also invites comparison with Bathyceramaster careyi or Bathyceramaster elegans, but the absence of underlying radial ossicles separates those species from Mediaster mollis n. sp. Occurrence. Western Indian Ocean, 452��� 833 m. Description. Body stellate (R/r=2.54���3.0), arms elongate with upturned or attenuated tips. Interradial arcs weakly curved to straight (Fig. 21A, E). Abactinal surface strongly distended. Abactinal plates short, columnar (i.e. weakly tabulate) with shallow fasciolar grooves throughout most of surface, flattening out with plates becoming more abutted distally on arm tips (Fig. 21C). Abactinal plates extending to arm tip from disk. Plates round to polygonal in outline, plates homogenous in shape, size proximally becoming smaller and more irregular in outline distally, adjacent to the superomarginal contact. Radial and adradial plates distinctly hexagonal in shape, especially proximally. Dissection of abactinal plate shows plates with four distinct bar-shaped ossicles radiating from each plate. These radiating plates with papular pores distributed between them. A bare region present along each radius along the inside of the abactinal plate surface where the two other radiating bars would be present in a comparable position. Abactinal plate surface covered by 15���60 coarse, round granules, approximately 2 to 2.5 granules counted along a 1.0 mm line. Granules form a widely spaced, single series, forming discrete boundary around the surficial edge of each plate, approximately 10���40 (about five to ten per side on most). Central surface granules widely spaced leaving shallow convexities on plate surface when removed. Granules present around edge form discrete cover extending over and obscuring fasciolar groove. Granular cover on abactinal plates present appearance of nearly continuous cover obscuring boundary between plates except where discontinuities or uneven surface integument are present. Granular cover is especially dense interradially adjacent to the superomarginal plate contact. Nearly every plate with one or two alligator-jaw like shaped pedicellariae (about 1.0 mm in length) valves each bearing six to 10 (mostly eight) teeth along the edge of each valve (Fig. 21B). Madreporite relatively flat, flush with abactinal surface, pentagonal to round in shape with five to seven plates surrounding it. Papulae six per plate, present at each edge. Marginal plates with primarily lateral facing, superomarginals, inferomarginals 62���66 (at R= 7.8 cm) per interradius (arm tip to arm tip), smallest individual with 34 (at R= 2.4 cm) per interradius with R= 3.8 cm showing 38 per interradius. Marginal plates elongate, rectangular in outline, especially interradially (Fig. 21D) becoming more quadrate in dimension distally near arm tip. Superomarginals and inferomarginals similar in size, but inferomarginals with pronounced actinal facing. Superomarginals lateral facing but with collapsed abactinal surface overhanging onto lateral side. Superomarginals and inferomarginals with some offset, forming zigzag contact between them. Marginal plate series transition from lateral facing to more abactinal distally along arm, especially at arm tip. Marginal plates surface with dense granular cover, approximately 100���200 covering each plate surface, granules identical in shape with that on abactinal surface (about 2.0���2.5 along a 1.0 mm lines). Granules show little to poor distinction between peripheral and central series. Each superomarginal and inferomarginal plate with one to three pedicellariae, identical to those present on abactinal surface, alligator-like in shape with six to eight teeth along the edge of each valve. Although pedicellariae are most strongly expressed interradially they do occur more distally along arms as well. Terminal plates triangular, smooth and flush with adjacent superomarginal plates. Actinal surface large, four to seven full rows in chevron formation (Fig. 21E), individual plates quadrate to round in shape with plates more irregular in size, shape distally adjacent to contact with inferomarginals. Actinal plates form weakly pronounced fasciolar grooves matched up with inferomarginal plate contacts. Actinal surface covered by abundant, but evenly spaced bullet-shaped granules covering the plate surface. Granules similar in shape with those on other surfaces, approximately 2 per 1.0 mm line. As with other surfaces, a small alligatorshaped or in some examples, an elongate tong-like shaped, pedicellaria is present, seated in a flat linear pit, present on the surface of most plates on the actinal intermediate region. Furrow spines 10���11, mostly 11 in larger specimens, with rounded, blunt tip, slender, compressed, quadrate in cross-section arranged in a weakly convex/palmate to straight formation (Fig. 21F). Adjacent to furrow spines are two distinct rows of subambulacral spines, each set off from the furrow spines with a discrete space (Fig. 21F). The first subambulacral spine row, adjacent to the furrow spines, composed of five spines, each about twice as thick as the furrow spines, quadrate in cross-section, with narrowing, rounded, blunt tips. Third row of subambulacrals composed of five short pointed granules, Material Examined. Holotype: IE-2013-17228 Western Indian Ocean 12�� 43 'S, 45 �� 19' E to 12�� 44 'S, 45�� 20' E, 664��� 617 m. Coll. S. Samadi et al. BIOMAGLO DW 4875 9 Feb. 2017. 1 wet spec. R=5.4 r=2.0. Paratypes: IE-2013-17206 Western Indian Ocean, 12��59���S, 44 �� 56' E to 12 �� 59 'S, 44 �� 55' E, 669��� 692 m. Coll. S. Samadi et al. BIOMAGLO CP 4858 4.2.17. 1 wet spec. R=5.8 r=1.9. IE-2013-17208 Western Indian Ocean, 12 �� 44 'S, 45 �� 19' E to 12�� 43 'S, 45�� 18' E. 452��� 462 m. Coll. S. Samadi et al. BIOMAGLO CP4876, 9.2.2017. 3 wet specs. R=5.6 r=2.2, R=6.6 r=2.3, R=7.8 r=2.9. IE-2013-17209 Western Indian Ocean 12 �� 25 'S, 43 �� 56' E to 12 �� 26 'S, 43 �� 56' E, 507��� 521 m.. Coll. S. Samadi et al. BIOMAGLO DW 4833. 28.01.17. 2 wet specs. R=7.1 r=2.8, R=7.9 r=3.2. IE-2013-17225 Western Indian Ocean 13 �� 0 'S, 44 �� 55' E to 13�� 1 'S, 44 �� 54' E. 757��� 795 m. Coll. S. Samadi et al. BIOMAGLO CP 4856 4.2.17. 1 wet spec. R=2.4 r=1.1. IE-2013-17227 Western Indian Ocean 13 �� 0 'S, 44 �� 55' E to 13 �� 1 'S, 44 �� 53' E, 742��� 833 m. Coll. S. Samadi et al. BIOMAGLO CP 4859, Feb. 4. 2017. 1 wet spec. R=3.8 r=1.4. IE-2013-17229 Western Indian Ocean 12 �� 30 'S, 44 �� 55' E to 12 �� 30 'S, 44 �� 55' E, 618��� 609 m. Coll. S. Samadi et al. BIOMAGLO DW 4862 9?2, 2017. 1 wet spec. R=5.3 r=2.1., Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 54-58, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/2615911, {"references":["Clark, H. E. S. & McKnight, D. G. (2001) The Marine Fauna of New Zealand: Echinodermata: Asteroidea (sea-stars), Order Valvatida. NIWA Biodiversity Memoir, 117, 1 - 270."]}