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The intricate geomorphology of the coastline in the Chilean Channels and Fjords region, together with the freshwater inputs from the ice fields provide the area with very unique ecological characteristics and a variety of habitats that favour great marine biodiversity. However, although Chilean Patagonia has been the focus of several expeditions and ecological surveys, the greatest emphasis has been either on the populated coasts of the Beagle Channel and the Straits of Magellan to the south or the area to the north of Golfo de Penas, leaving vast areas that remain largely unexplored. This leads to a latitudinal gap in the faunistic information and hinders zoogeographic studies to assess biogeographical connections along the eastern coasts of the Pacific. Peracarida is a taxonomic group that provides an excellent model for such studies because of their high abundance and biodiversity, benthic habits, small size and limited dispersal capacity. A dataset providing the first and only records of the benthic Peracarida between the latitudes 48–51.5°S of the Pacific coast of Chile is presented here, hence closing a geospatial gap for the study of the biogeographical connections of the Peracarida along the Eastern Pacific coast. The dataset comprises a total of 141 georeferenced records of 60 sublittoral species of Tanaidacea, Isopoda and Amphipoda. This and other studies reveal that the coastal fauna of the region follow a latitudinal distribution pattern at a larger scale and nested assemblages inside the channels and fjords that can be regarded as a consequence of the more restrictive conditions in the inner parts. In the present scenario of global warming that is expected to affect particularly polar and subpolar regions, the present dataset serves as a reference for the distribution patterns of benthic organisms with low dispersal capacity.

The offspring of skate Bathyraja sp., caught in the environs of the Simushir Island (Greater Kuril Chain), were studied for infections and stomach contentment. Three species of cestodes: Onchobothrium sp., Pseudanthobothrium purtoni, and Phyllobothrium georgiense were found. Eight taxa of invertebrates were found in the stomach: seven amphipods Acanthostepheia behringiensis, Ampelisca eschrichtii, Eusirus cuspidatus, Gammaridea fam. gen. sp., Lysianassidae gen. sp., Oedicerotidae gen. sp., Stenothoidae gen. sp., and one isopod Arcturus crenulatus. The explosive increase in the number of cestodes infecting Bathyraja sp., has been caused by a change in the food spectrum, characterized by the appearance of bony fish. It is the first time that these three species of cestodes have been recorded in the Bathyraja (inhabiting the Northwestern Pacific). The obtained data expands knowledge on the feeding of skates, the fauna of cestodes of the North Pacific Ocean, and their final hosts, as well as coastal communities of the middle Kuril Islands that are poorly studied.

Current information on soft-bottom benthic amphipod species of the south coasts of Cyprus is scarce. In the summer of 2013, a research survey was carried out, targeting the Vasiliko Bay and the nearby coastal area which is influenced by multiple human-induced stressors. Analysis of 126 samples revealed the presence of 2,122 individual amphipods (Amphilochidea and Senticaudata) belonging to 25 families and 52 species. Twenty-four species are new records for Cyprus increasing the number of amphipods to 141 species. In Vasiliko Bay, two amphipod species presented the highest abundances and were found to be constant (Microdeutopus periergos, Perioculodes longimanus), while seven are common species (Ampelisca brevicornis, Ampelisca typica, Apherusa chiereghinii, Dexamine spinosa, Harpinia crenulata, Leptocheirus pectinatus, Leucothoe incisa) and the remaining 43 species are rare. The highest amphipod total abundances and number of species were recorded in stations with dense Posidonia oceanica meadows and aquaculture units in the vicinity. Brief distributional and ecological characteristics of the identified amphipod species are given and an annotated checklist for the coasts of Cyprus is provided.

14. Lepidepecreum longicornis (Spence Bate, 1862) Materials examined. 9 individuals; Stations Vas. 1(1), 2(1), 3(1), 30(2), 37(1), 38(3). Distribution. Atlanto-Mediterranean (Bellan-Santini & Ruffo 2003). The species is reported in Cyprus for the first time. In Vasiliko Bay it is considered to be a rare species (FI: 14.28 %). Ecology. In Vasiliko Bay it was found at depths of 5���35 m (19 + 14 m), mainly in muddy sand and also sand substrates, with organic matter ranging between 1.859 ���8.416 % (5.166 + 2.968 %), and in association with C. prolifera and C. cylindracea. It was found in stations classified according to the Bentix Index as in: ���high��� (1 station, 1 individual), ���good��� (1 station, 1 individual) and ���moderate��� (4 stations, 7 individuals). It was recorded at a fish farm station (1 individual) and the port (1 individual)., Published as part of Rousou, Maria, Plaiti, Wanda, Lowry, Jim, Charalambous, Stephanos & Chintiroglou, Chariton Charles, 2020, Amphipoda species (Suborders: Amphilochidea and Senticaudata) from Vasiliko Bay, Cyprus: New records, information on their biogeography and an annotated checklist from the coasts of Cyprus, pp. 373-408 in Zootaxa 4896 (3) on page 385, DOI: 10.11646/zootaxa.4896.3.3, http://zenodo.org/record/4383886, {"references":["Spence Bate, C. S. (1862) Catalogue of the Specimens of Amphipodous Crustacea in the Collection of the British Museum. British Museum (Natural History), London, iv + 399 pp., 56 pls. https: // doi. org / 10.5962 / bhl. title. 20901","Bellan-Santini, D. & Ruffo, S. (2003) Biogeography of benthic marine amphipods in Mediterranean Sea. Biogeographia-The Journal of Integrative Biogeography, 24 (1), 273 - 292. https: // doi. org / 10.21426 / B 6110176"]}

15. Lysianassa costae H. Milne Edwards, 1830 Materials examined. 4 individuals; Stations Vas. 2(1), 30(1), 35(2). Distribution. Atlanto-Mediterranean (Bellan-Santini & Ruffo 2003; Christodoulou et al. 2013). The species was reported from Cyprus by Russo (1997), Kocatas et al. (2001) and Christodoulou et al. (2013). In Vasiliko Bay (current study), it is considered as a rare species (FI: 7.14 %). Ecology. Lysianassa costae was found in association with algae, on rocks and stones and in soft-bottom sediments (mud, mud-and mixture) at 1���150 m depth (Kocatas et al. 2001; Christodoulou et al. 2013). In Vasiliko Bay it was found at depths of 20���35 m (29 + 8 m), in muddy sand substrate with organic matter ranging between 6.265 ���8.416 % (7.459 + 1.095 %) and in association with C. prolifera, C. cylindracea and P. oceanica. It was found in stations classified as ���moderate��� according to the Bentix Index. It was also recorded at a fish farm station (1 individual)., Published as part of Rousou, Maria, Plaiti, Wanda, Lowry, Jim, Charalambous, Stephanos & Chintiroglou, Chariton Charles, 2020, Amphipoda species (Suborders: Amphilochidea and Senticaudata) from Vasiliko Bay, Cyprus: New records, information on their biogeography and an annotated checklist from the coasts of Cyprus, pp. 373-408 in Zootaxa 4896 (3) on page 385, DOI: 10.11646/zootaxa.4896.3.3, http://zenodo.org/record/4383886, {"references":["Milne Edwards, H. (1830) Extrait de recherches pour servir a l'histoire naturelle des crustaces amphipodes. Annales des Sciences Naturelles, 20, 353 - 399. https: // doi. org / 10.5962 / bhl. part. 12300","Bellan-Santini, D. & Ruffo, S. (2003) Biogeography of benthic marine amphipods in Mediterranean Sea. Biogeographia-The Journal of Integrative Biogeography, 24 (1), 273 - 292. https: // doi. org / 10.21426 / B 6110176","Christodoulou, M., Paraskevopoulou, S., Syranidou, E. & Koukouras, A. (2013) The amphipod (Crustacea: Peracarida) fauna of the Aegean Sea, and comparison with those of the neighbouring seas. Journal of the Marine Biological Association of the United Kingdom, 93 (5), 1303 - 1327. https: // doi. org / 10.1017 / S 002531541200183 X","Russo, A. R. (1997) Epifauna living on sublittoral seaweeds around Cyprus. Hydrobiologia, 344, 169 - 179. https: // doi. org / 10.1023 / A: 1002970714963","Kocatas, A., Katagan, T. & Huseyin. A. B. (2001) Contribution to the knowledge of the crustacean fauna of Cyprus. Israel Journal of Zoology, 47 (2), 147 - 160. https: // doi. org / 10.1560 / YQL 8 - 4 PBT- 12 W 2 - 82 HV"]}

Coralline intertidal habitats of marine protected areas, are important model systems to investigate species diversity and ecological functioning of benthic communities. Spatial variability of amphipod species composition and functional traits were studied over a three year period during the summer season at five intertidal transects of the Gulf of Kachchh Marine Protected Area, India. A total of 22,706 individuals, comprising 71 species belonging to 40 genera and 23 families were identified. Aoridae, Dexaminidae, Eriopisidae, Lysianassidae and Maeridae were the best represented families (68.2% of total abundance). Distinct spatial patterns in the amphipod assemblage structure and functional traits were observed along the horizontal and vertical axes. The results demonstrated that the amphipod assemblage functioning was greatly influenced by the vertical gradient, with generally higher functional diversity in the lower intertidal zones suggesting increased diversity in resource use strategies, whereas the upper zones showed very little functional diversity possibly due to the prevalence of environmental filtering. As higher species and functional diversities promote better resource partitioning and resilience of the ecosystem, these results are important for the management of marine protected areas facing the dual challenges of global climate change and anthropogenic pressures.

Lepidepecreoides stoddartae sp. nov. (Figs 1, 2) Type material. Holotype female, dissected, 11.0 mm, NHMUK 2018.903, North Falkland Basin, Falkland Islands, South West Atlantic (49��21���31.701���S, 59��8���21.478���W), 341 m, Brown silty clay occasional pebble, 24 December 2012, Box Corer, RRS Ernest Shackleton, Sea Lion Field Development Environmental Baseline Survey (43 MFC). Paratypes: 1 specimen unsexed, 7.1 mm, NHMUK 2018.755, North Falkland Basin, Falkland Islands, South West Atlantic (49��21���29.380���S, 59��3���24.061���W), 434 m, Brown silty clay occasional pebble, 14 April 2012, Box Cor- er, RRS Ernest Shackleton, Sea Lion Field Development Environmental Baseline Survey (46 MFB); 3 gravid female specimens, all 10 mm, NHMUK 2018.899, North Falkland Basin, Falkland Islands, South West Atlantic (49��19���21.438���S, 59��6���44.668���W), 450 m, Brown silty clay occasional pebble, 15 April 2012, Box Corer, RRS Ernest Shackleton, Sea Lion Field Development Environmental Baseline Survey (33 MFC); 1 juvenile specimen, 5.0 mm, NHMUK 2018.900, North Falkland Basin, Falkland Islands, South West Atlantic (49��20���27.670���S, 59��10���1.713���W), 436 m, Brown silty clay occasional pebble, 15 April 2012, Box Corer, RRS Ernest Shackleton, Sea Lion Field Development Environmental Baseline Survey (37 MFA); 1 juvenile specimen, 5.0 mm, NHMUK 2018.901, North Falkland Basin, Falkland Islands, South West Atlantic (49��21���32.428���S, 59��10���0.6200���W), 434 m, Brown silty clay occasional pebble, 14 April 2012, Box Corer, RRS Ernest Shackleton, Sea Lion Field Development Environmental Baseline Survey (42 MFA); 2 specimens unsexed (7.0 mm, 8.5 mm), NHMUK 2018.902, North Falkland Basin, Falkland Islands, South West Atlantic (49��21���32.428���S, 59��10���0.620���W), 434 m, Brown silty clay occasional pebble, 14 April 2012, Box Corer, RRS Ernest Shackleton, Sea Lion Field Development Environmental Baseline Survey (42 MFC); 1 juvenile specimen, 4.0 mm, NHMUK 2018.1005, North Falkland Basin, Falkland Islands, South West Atlantic (49��18���15.113���S, 59��3���27.771���W), 453 m, Brown silty clay occasional pebble, 15 April 2009, Box Corer, RRS Ernest Shackleton, Sea Lion Field Development Environmental Baseline Survey (29 MFA); 1 specimen unsexed, 8.0 mm, NHMUK 2018.754, Falkland Islands, South West Atlantic Ocean, no GPS, RPS North Falklands Drill Site seafloor mining lease (Rhea 1), depth unknown, 26 August 2015, Box Corer, RRS Ernest Shackleton (ENV11 FC); 1 juvenile specimen, 4.1 mm, NHMUK 2018.699, Falkland Islands, South West Atlantic Ocean, no GPS, RPS North Falklands Drill Site seafloor mining lease (Rhea 1), depth unknown, 26 August 2015, Box Corer, RRS Ernest Shackleton (ENV11 FC). Type locality. North Falkland Basin, Falkland Islands, South West Atlantic (49��21���31.701���S, 59��8���21.478���W). Etymology. Named in honour of Helen Stoddart for her significant contribution to lysianassoid taxonomy. Comparative material examined. Lepidepecreoides xenopus K.H. Barnard, 1931, Holotype male, 9.0 mm, BMNH 1936.11.2.334, Palmer Archipelago, Antarctica. Non-type Female, 11.0 mm, BMNH 1936.11.2.335, South Shetland Islands. Description. Head with lateral cephalic lobe subtriangular, apically subacute; eyes apparently absent. Pereonites 1���7 without mid-dorsal carina. Pleonites 1���2 mid-dorsal carina produced as small hump. Pleonite 3 mid-dorsal carina as small hump, posterodorsal margin produced. Urosomite 1 with recurved, apically rounded produced boss. Antenna 1 peduncular articles 1 and 2 without anterodistal lobe; accessory flagellum 3-articulate, terminal article small, offset; flagellum with strong 2-field callynophore; robust setae present on proximal articles; calceoli absent. Antenna 2 flagellum short, calceoli absent. Epistome rounded. Mandible molar columnar with oval, fully triturating surface; palp attached distally, article 3 with proximal A3-seta. Maxilla 1 outer plate with left and right setal-tooth 11 symmetrical, cuspidate distally along inner margin; palp distal margin with 12 apical robust setae. Maxilliped not observed (?damaged). Gnathopod 1 subchelate; coxa large, about as long as coxa 2, subrectangular; basis sparsely setose along anterior margin; ischium short; carpus long, length 4 times breadth, longer than propodus, without posterior lobe; propodus small, margins subparallel, palm angle acute, defined by robust seta. Gnathopod 2 parachelate, palm convex. Pereopod 4 coxa with small posteroventral lobe (posterior margin concave). Pereopod 5 coxa with distinct lateral ridge; basis about as long as broad, posterior margin with well developed mid-central spine, spine longer than broad, apically rounded, posteroventral lobe rounded. Pereopod 6 basis posterior margin serrate. Pereopod 7 basis posterior margin serrate, posterodistally rounded, produced, not reaching merus. Epimeron 3 posterior margin smooth, posteroventral corner broadly rounded. Uropod 3 outer ramus article 2 short; with plumose setae on each ramus. Telson deeply cleft, with 2���3 apical robust seta on each lobe. Remarks. Lepidepecreoides stoddartae sp. nov. can be distinguished from other species in the genus by the acute palm of gnathopod 1 and the more elongate posterior projection on the basis of pereopods 5. The presence of the pereopod 5 projection is a defining character for the genus, the dorsal and ventral margins of the projection and its more proximal position along the posterior margin of the basis in L. stoddartae sp. nov. is most similar to L. xenopus. The serrations along the posterior margin of pereopods 6 to 7 in L. stoddartae sp. nov., is similar to L. bassi and L. xenopus however in the latter two species the serrations are not as well-developed. The pleonite 3 dorsal projecting boss is more recurved and apically rounded in L. stoddartae sp. nov. compared with L. bassi and L. xenopus which have a more acute boss projection with a straight posterior margin. Both L. stoddartae sp. nov. and L. xenopus are recorded from the South Atlantic, currently L. stoddartae is known only from areas around the Falkland Islands, while L. xenopus has been more extensively within the Antarctic region (Table 1). Lepidepecreoides xenopus is the type species for the genus with the type locality South Georgia, it is perhaps not particularly remarkable that the two most morphologically similar species, L. stoddartae sp. nov. and L. xenopus, also have geographically proximate distributions. Lepidepecreoides stoddartae sp. nov. was collected at 341 to 453 m depth, which is similar to previous records of Lepidepecreoides (Table 1). The collection here includes 12 individuals from eight sampling events. This is a particularly high number of specimens. Most Lepidepecreoides species are known from only one or few specimens across six expeditions (one specimen��� L. bassi, L. nubifer, L. talboti, L. torresi; three specimens L. chincui and L. xenopus eight specimens). Other studies have recorded a maximum of three specimens from the same sample (L. xenopus USNM306582 Weddell Sea, Lowry & Stoddart, 2002) (Table 1)., Published as part of Hughes, Lauren Elizabeth, 2020, Lepidepecreoides stoddartae sp. nov. from the Falkland Islands (Amphipoda: Tryphosidae), pp. 108-114 in Zootaxa 4816 (1) on pages 109-113, DOI: 10.11646/zootaxa.4816.1.7, http://zenodo.org/record/3954157, {"references":["Barnard, K. H. (1931) Diagnosis of new genera and species of amphipod Crustacea collected during the Discovery investigations, 1925 - 1927. Annals and Magazine of Natural History, Series 10, 7, 425 - 430. https: // doi. org / 10.1080 / 00222933108673327","Lowry, J. K. & Stoddart, H. E. (2002) The lysianassoid amphipod genera Lepidepecreoides and Lepidepecreum in southern waters (Crustacea: Lysianassidae: Tryphosinae). Records of the Australian Museum, 54 (3), 335 - 364. https: // doi. org / 10.3853 / j. 0067 - 1975.54.2002.1329","Barnard, J. L. (1971) Gammaridean Amphipoda from a deep-sea transect off Oregon. Smithsonian Contributions to Zoology, 61, 1 - 86. https: // doi. org / 10.5479 / si. 00810282.61"]}

Key to species of Lepidepecreoides (following Lowry & Stoddart, 2002) 1 Pleonite 3 produced dorsodistally........................................................................ 2 - Pleonite 3 not produced dorsodistally..................................................................... 5 2 Gnathopod 1 subchelate................................................................................ 3 - Gnathopod 1 simple........................................................ L. chincui Lowry & Stoddart, 2002 3 Pereopod 5 basis with rounded posteroventral lobe. Telson with apical robust setae................................. 4 - Pereopod 5 basis with wedge-shaped posteroventral lobe. Telson without apical robust setae..................................................................................................... L. bassi Lowry & Stoddart, 2002 4 Gnathopod 1 palm angle subacute................................................ L. xenopus K.H. Barnard, 1931 - Gnathopod 1 palm angle acute........................................................... L. stoddartae sp. nov. 5 Telson with apical robust setae............................................................................6 - Telson without apical robust setae............................................. L. talboti Lowry & Stoddart, 2002 6 Gnathopod 1 palm acute. Coxa 5 without lateral ridge. Urosomite 1 boss produced dorsally into a recurved spine...................................................................................... L. nubifer J. L. Barnard, 1971 - Gnathopod 1 palm slightly acute. Coxa 5 with distinct lateral ridge. Urosomite 1 boss produced dorsally into a broad upright triangle................................................................... L. torresi Lowry & Stoddart, 2002, Published as part of Hughes, Lauren Elizabeth, 2020, Lepidepecreoides stoddartae sp. nov. from the Falkland Islands (Amphipoda: Tryphosidae), pp. 108-114 in Zootaxa 4816 (1) on page 113, DOI: 10.11646/zootaxa.4816.1.7, http://zenodo.org/record/3954157, {"references":["Lowry, J. K. & Stoddart, H. E. (2002) The lysianassoid amphipod genera Lepidepecreoides and Lepidepecreum in southern waters (Crustacea: Lysianassidae: Tryphosinae). Records of the Australian Museum, 54 (3), 335 - 364. https: // doi. org / 10.3853 / j. 0067 - 1975.54.2002.1329","Barnard, K. H. (1931) Diagnosis of new genera and species of amphipod Crustacea collected during the Discovery investigations, 1925 - 1927. Annals and Magazine of Natural History, Series 10, 7, 425 - 430. https: // doi. org / 10.1080 / 00222933108673327","Barnard, J. L. (1971) Gammaridean Amphipoda from a deep-sea transect off Oregon. Smithsonian Contributions to Zoology, 61, 1 - 86. https: // doi. org / 10.5479 / si. 00810282.61"]}

Hughes, Lauren Elizabeth (2020): Lepidepecreoides stoddartae sp. nov. from the Falkland Islands (Amphipoda: Tryphosidae). Zootaxa 4816 (1): 108-114, DOI: https://doi.org/10.11646/zootaxa.4816.1.7

Two new species of the genus Microlysias Stebbing, 1918 belonging to the family Tryphosidae Lowry & Stoddard, 1997 were collected from shallow Korean waters. The two new species are described as Microlysias rectangulatus and M. triangulus. The new species M. rectangulatus sp. nov. is similar to M. xenokeras, M. soela, and Orchomenella japonica. However, the new species can be distinguished from these species by having a subrectangular peduncular article 5 of antenna 2 and an elongated article 1 of the mandibular palp, nearly equal to palp article 3. M. triangulus sp. nov. is similar to M. xenokeras and M. soela. However, this species is characterized by the triangular shaped peduncular article 5 of antenna 2 and the slender propodus of gnathopod 1. These species are illustrated and compared to related species.

Microlysias triangulus n. sp. (Korean Name: Se-mo-deo-deum-i-gin-pal-yeop-sae-u, new) (Figs. 7���10) Type material. Holotype, adult male, 11.2 mm, cat no. NIBRIV0000865028, Nokdo Island, Nokdo-ri, Ocheonmyeon, Boryeong-si, Chungcheongnam-do, Korea, 36�� 16��� 07���N, 126�� 15��� 59���E, 21 November 2001, collected by Y. Eun. Paratypes, 1 adult female, 7.0 mm, cat no. NIBRIV0000865030; 1 immature male, 10.1 mm, cat no. NIBRIV0000865029 (dissected), data same as holotype; 1 ♂, CMNC 2020-0002. Etymology. The species name is from the Latin triangulus (triangle), referring to the expanded, triangular shaped peduncular article 5 of male antenna 2. Description. Holotype adult male. Body (Fig. 7A) dorsally smooth; head (Fig. 8A), lateral cephalic lobe produced, subacute apically; eyes ovoid, black, medium; epimeron 1 (Fig. 8B) posterior margin smooth, rounded posteroventrally; epimeron 2 (Fig. 8B) subquadrate posteroventrally; epimeron 3 (Fig. 8B) subquadrate, posterior margin slightly convex, all epimera with pubescence ventrally and without serration posteriorly; urosomite 1 (Fig. 8B) with a weak, dorsal depression and low, rounded carina, which slightly overhangs urosomite 2. Antenna 1 (Fig. 8C) stout, short, length 0.33 x antenna 2; peduncular article 1 longer than peduncular articles 2���3 combined, with a row of 7 penicillate setae dorsally; peduncular articles 2���3 short subequal in length; length ratio of peduncular articles 1���3=1.00: 0.22: 0.21; flagellum 9-articulate, subequal in length to peduncle, with stout callynophore, calceoli absent; accessory flagellum 4-articulate, article 1 elongate, much longer than the other articles combined. Antenna 2 (Fig. 8D) elongate; peduncular article 5 characteristic in form, subtriangular, length=width, broadly gibbous ventrally, length 1.79 x article 4; flagellum 74-articulate, article 1 elongate, length 0.68 x peduncular article 5, calceoli absent. Right mandible (Fig. 8E), incisor smooth, with 1 tiny sharp tooth on the lower side; lacinia mobilis absent; accessory setal row with 6 spines; molar elongate and forms a setose ridge; palp 3-articulate, attached slightly proximal to molar; article 1 unarmed, elongated, length 0.61 x article 3; article 2 longest, with a row of 10 A2-setae; article 3 weakly falcate, length 0.91 x article 2, with 1 A3-seta, 12 D3-setae, and 3 E3-setae. Left mandible (Fig. 8F) similar to left except lacinia mobilis present as a simple peg-like spine, and accessory setal row with 8 spinules. Maxilla 1 (Fig. 8G), inner plate slender, with 2 pectinate setae apically and setules on inner margin, lacking apical spine; outer plate with 11 dentate spine-teeth; palp narrowly rectangular, biarticulate, curved, proximal article short, distal article with 5 blunt spines and 1 simple seta apically. Maxilla 2 (Fig. 8H), inner plate slender, with 1 pappose and 9 simple setae apically, medial margin with pubescence; outer plate slender, length 1.23 x inner one, with pectinate and simple setae apically, both margins covered with pubescence. Maxilliped (Fig. 8I), inner plate subrectangular, with 2 pectinate setae medially, apical margin with bifid cutting edge and 2 simple setae; outer plate elongate semielliptical, reaching distal end of article 2 of palp, with a row of 4 spinules medially; palp 4-articulate, articles 1���3 with simple setae medially and laterodistally; article 4 falcate, shorter than article 3. Gnathopod 1 (Fig. 8J) subchelate; coxa large, widening distally, roundly produced anteroventrally, width 0.66 x length; basis with simple setae along anterior margin; merus, and carpus subequal in length with pubescence ventrally, carpus with short lobe ventrally; propodus subrectangular, narrowing distally, length 2.50 x width, slightly concave ventrally, length 1.41 x carpus; palm short, serrulate, gently convex, defined by 2 spines posterodistally; dactylus falcate, with an accessory tooth, fitting palm. Gnathopod 2 (Fig. 9A), coxa subrectangular, width 0.41 x length; basis slender, elongate, with 1 simple seta posterodistally; ischium elongate, with 5 simple setae on posterior margin, subequal in length to carpus; merus length 0.73 x ischium, with patch of setules posteriorly and unequal simple setae posterodistally; carpus gradually widening distally, with 7 simple setae distally, half of ventrodistal surface covered with pubescence; propodus subovate and narrow, length 2.43 x width, minutely chelate, with 4 rows of pectinate setae medially, length 0.46 x carpus; dactylus acute, fitting palm. Pereopod 3 (Fig. 9B), coxa subrectangular, unarmed; basis narrowing proximally, with 6 simple setae anteriorly and 3 simple setae posterodistally; merus length 1.82 x carpus, produced anterodistally, with 14 simple setae posteriorly; propodus subrectangular, slender, length 1.35 x carpus, with a row of 5 spines posteriorly; dactylus falcate, length 0.30 x propodus. Pereopod 4 (Fig. 9C) similar to pereopod 3 except coxa much broader than that of pereopod 3, posterior margin excavate, posterodistal lobe produced, truncated, posteroventral corner rounded. Pereopod 5 (Fig. 9D), coxa large, rounded quadrate, weakly bilobate, length 1.16 x width; basis broadly subcircular, width 1.07 x length, posterior margin weakly serrate, posteroventral lobe broadly rounded; with a row of spines and 12 simple setae along anterior margin; merus expanded posteriorly, anterior margin with 6 simple setae, posterior margin with 4 simple setae; propodus rectangular, length 1.46 x carpus, anterior margin with a row of 4 paired spines; dactylus falcate, length 0.42 x propodus. Pereopod 6 (Fig. 9E), coxa subequal to coxa 7, weakly bilobate, posterior lobe produced posteroventrally; basis subovate, with a row of spines on distal half of anterior margin, posterior margin weakly serrate; merus expanded posteriorly, anterior margin with 6 long simple setae and 5 spines, posterior margin with 3 spines; propodus rectangular, length 1.25 x carpus, anterior margin with 4 paired spines; dactylus falcate, length 0.35 x propodus. Pereopod 7 (Fig. 9F) similar to pereopod 6, but coxa not lobate; basis broader than that of pereopod 6, posterior margin convex and weakly serrate; merus narrow, not expanded. Uropod 1 (Fig. 10A), peduncle subrectangular, length 1.67 x outer ramus, with row of spines on dorsolateral and dorsomedial margins; rami lanceolate, outer ramus slightly longer than inner one, dorsolateral margin with 4 spines; inner ramus with 3 spines on both dorsolateral and medial margins. Uropod 2 (Fig. 10B), peduncle longer than outer ramus, with 3 spines dorsolaterally; outer ramus slightly longer than inner one, with 4 dorsolateral spines; inner ramus with 3 dorsolateral and 2 dorsomedial spines. Uropod 3 (Fig. 10C), peduncle short, much shorter than outer ramus, with 5 spines distally; outer ramus biarticulate, length 1.17 x inner ramus, proximal article with 11 long plumose setae along inner margin, outer margin with 6 spines; distal article short, length 0.17 x proximal one; inner ramus broad, not reaching base of distal article of outer ramus, outer margin with 15 long plumose setae, inner margin with 2 spines and 3 plumose setae. Telson (Fig. 10D) much longer than broad, length 1.62 x width, deeply cleft, 74% of its length, each lobe with a pair of penicillate setae and 3 spines dorsolaterally, 1 spine and 1 penicillate seta apically. Paratype, immature male. 10.1 mm. Antenna 1 (Fig. 10E, F) similar to that of adult male; peduncular article 1 with 2 penicillate setae distally; flagellum 9-articulate, calceoli absent. Antenna 2 (Fig. 10E, G) short; similar to that of adult male, but peduncular article 5 less expanded ventrally; flagellum 54-articulate, compressed, much shorter than that of adult male, calceoli absent. Paratype, adult female. 7.0 mm. Head (Fig. 10H) similar to that of adult male; cephalic lobes slightly narrower and rounded. Antenna 1 (Fig. 10I) similar to that of adult male; peduncular article 1 with 4 penicillate setae ventrally; flagellum 8-articulate; callynophore present, calceoli absent. Antenna 2 (Fig. 10J) short, subequal in length to antenna 1; peduncular articles 4���5 subrectangular, narrow, without ventral expansion; flagellum 6-articulate, much shorter than that of adult male. Uropod 3 (Fig. 10K) stout, inner ramus narrower than male and with less plumose setae than male. Depth range. 20���30 m Remarks. The relative position of the palp attached to the mandibular body has traditionally been an important character in higher level systematics in lysianassids. However, the form of the palp is as important as the relative position. Elongation of the first article of the palp is an unusual character in lysianassids. Barnard & Karaman (1991) mentioned that the mandibular palp of the genus Microlysias is attached strongly proximal to the molar, but this diagnosis was based on only a single species, M. xenokeras . However, Lowry and Kilgallen (2014), showed that M. xenokeras and M. soela have slightly differing positions of the mandibular palp, but they are all proximal to the molar. The character of the mandible in the genus Microlysias should be emended as follows: mandibular palp is attached slightly to strongly proximal to the molar. Microlysias triangulus sp. nov. is similar to M. xenokeras Stebbing, 1918, M. soela Lowry & Kilgallen, 2014 and M. rectangulatus sp. nov. (this paper) in having a broadened male peduncular article 5 of antenna 2. However, M. triangulus is distinguished from its congeners as follows: 1) antenna 2, peduncular article 5 characteristic in form, subtriangular (vs. subquadrate in M. xenokeras, M. soela and M. rectangulatus); 2) gnathopod 1, propodus elongate and slender, length 2.50 x width (vs. stouter in M. xenokeras, 2.10 x width, M. soela, 1.73 x width and M. rectangulatus, 2 x width). As well, from M. xenokeras, it differs in the much stouter gnathopod 2 propodus and narrower pereopod 5 basis. From M. soela it also differs in the much smaller eyes, lack of maxilla 1 inner plate apical spine projection and slender maxilla 2. From M. rectangulatus sp. nov. (this paper) it also differs in the narrower propodus of gnathopods 1���2, much shorter article 1 of the mandibular palp and smooth posterior margins of epimeron plates 2���3. Microlysias triangulus is also the largest species, with males reaching 11.2 mm vs 7.6 mm in M. rectangulatus and 6 mm in M. xenokeras and M. soela. The type species, M. xenokeras was collected from ascidians (Stebbing, 1918). Lowry & Kilgallen (2014) mention that crinoids were in one of the collections of M. soela, but did not specifically mention any direct association. We have no information from our collections whether or not M. triangulus were associated with any other invertebrates when collected. If Microlysias species are commonly found to be associated with sessile invertebrates, we can expect many other species to be eventually described in the future. We have no direct evidence of the feeding type of M. triangulus, but as M. rectangulatus is a carnivorous/scavenging species, it may be inferred that M. triangulus may also have a similar feeding habit. Distribution. Korea (Nokdo-island, Boryeong-si)., Published as part of Heo, Jun-Haeng, Hendrycks, Ed A. & Kim, Young-Hyo, 2020, Two new species of the genus Microlysias (Crustacea, Amphipoda, Tryphosidae) from Korean Waters, pp. 543-556 in Zootaxa 4759 (4) on pages 550-555, DOI: 10.11646/zootaxa.4759.4.5, http://zenodo.org/record/3741063, {"references":["Barnard, J. L. & Karaman, G. S. (1991) The families and genera of marine gammaridean Amphipoda (except marine gammaroids). Records of The Australian Museum, Supplement 13, 1 - 866. https: // doi. org / 10.3853 / j. 0812 - 7387.13.1991.367","Lowry, J. K. & Kilgallen, N. M. (2014) New tryphosine amphipods from Australian waters (Crustacea, Amphipoda, Lysianassoidea, Lysianassidae, Tryphosinae). Zootaxa, 3844 (1), 1 - 64. https: // doi. org / 10.11646 / zootaxa. 3844.1.1","Stebbing, T. R. R. (1918) Some Crustacea of Natal. Annals of the Durban Museum, 2, 47 - 75, pls. 8 - 12."]}

Microlysias rectangulatus sp. nov. (Korean Name: Ne-mo-deo-deum-i-gin-pal-yeop-sae-u, new) (Figs. 2���6) Type material. Holotype, adult male, 7.6 mm, cat no. DKU-099, Gajin-port, Gajin-ri, Jugwang-myeon, Goseonggun, Gangwon-do, Korea, 38�� 22���05���N, 128�� 30���45���E, 02 February 2008, collected by Y.H. Kim. Paratypes, 1 adult female, 8.6 mm, cat no. DKU-100, data same as holotype (dissected), 2 ♂, 10 ♀, CMNC 2020-0001, data same as holotype and the remaining paratypes (8 ♂, 50 ♀, DKUAMP202001) in the collection of the corresponding author. Etymology. The species name is from the Latin quadratus (square, four-cornered), referring to the expanded subrectangular peduncular article 5 of male antenna 2. Description. Holotype adult male. Body (Fig. 3A) dorsally smooth; head (Fig. 4A), lateral cephalic lobe subacute, triangular apically; eyes large, ovoid, black; epimeron 1 posterior margin smooth and convex; epimeron 2, posteroventral corner right angled, posterior margin minutely serrated; epimeron 3 posteroventral corner subquadrate, posterior margin minutely and irregularly serrated; urosomite 1 with dorsal depression and mid-dorsal carina, posterolateral margin minutely serrated (Fig. 4B). Antenna 1 (Fig. 4A, C) stout, length 0.34 x antenna 2; peduncular article 1 much longer than peduncular articles 2���3, with a row of 7 simple setae dorsally; length ratio of peduncular articles 1���3=1.00: 0.20: 0.17; flagellum 12- articulate, calceoli absent, subequal in length to peduncle, with 2-field callynophore; accessory flagellum 5-articulate, article 1 rather elongate, shorter than other articles combined. Antenna 2 (Fig. 4A, D) elongate; peduncular articles 1���4 rather short; peduncular article 5, subquadrate, length 1.45 x width, broadening ventrodistally; flagellum 51-articulate, first article elongated, calceoli absent. Epistome (Fig. 4A) roundly produced, projecting above upper lip. Lower lip (Fig. 4E), inner lobes indistinct; outer lobe pubescent medially; mandibular lobes narrow. Left mandible (Fig. 4F), incisor simple, smooth; lacinia mobilis simple, slender; accessory setal row with 3 spines and patch of setules; molar slightly elongate, narrow and forms a setose ridge; palp 3-articulate, attached strongly proximal to molar; article 1 unarmed, very long, length 0.98 x article 3; article 2 longest, with 10 A2-setae; article 3 weakly falcate, length 0.64 x article 2, with 1 A3-seta, 14 D3-setae, and 2 E3-setae. Right mandible (Fig. 4G), incisor smooth and without tooth; lacinia mobilis absent; accessory spine row with 5 spines; the other morphological characters generally similar to left mandible. Maxilla 1 (Fig. 4H), inner plate slender, subrectangular, with 2 pectinate setae apically and setules on outer margin, lacking apical spine; outer plate with 11 dentate spine-teeth; palp biarticulate, proximal article short, distal article not expanded, with 1 slender and 4 blunt apical spines. Maxilla 2 (Fig. 4I), inner plate slender, slightly shorter than outer, with 14 apical setae, medial margin with pubescence; outer plate 1.08 x longer than inner one, with pectinate and simple setae distally. Maxilliped (Fig. 4J), inner plate rectangular, with 2 pectinate setae medially, apical margin with 2 unequal simple setae and 3 blunt spines; outer plate subovate, exceeding distal end of article 2 of palp, with 10 spines medially and 4 simple setae on inner margin; palp 4-articulate, article 1 slightly shorter than article 2, with 2 simple setae on inner margin, 1 simple seta laterodistally; article 2 with 11 simple setae on inner margin, 1 simple seta laterodistally; article 3 with simple setae on inner and distal margins; article 4 falcate, shorter than article 3. Gnathopod 1 (Fig. 5A) subchelate; coxa large, broadly rounded anterodistally and expanded, width 0.69 x length; basis subrectangular, with 15 simple setae anteriorly; ischium with 5 simple setae posteriorly; merus with pubescence posteriorly and simple setae posterodistally; carpus subtriangular, shorter than propodus, with short ventral lobe, with 2 clusters of simple setae distally; propodus rectangular, slightly narrowing distally, length 2 x width, slightly concave posteriorly, length 1.44 x carpus; palm short, serrulate, transverse, defined by 1 stout spine posterodistally; dactylus falcate, fitting palm. Gnathopod 2 (Fig. 5B), coxa subrectangular, gradually widening distally, width 0.43 x length; basis slender, elongate, with 1 simple seta posterodistally; ischium elongate, with 6 simple setae on posterior margin, subequal in length to carpus; merus length 0.73 x ischium, with patch of setules posteriorly and 3 simple setae posterodistally; carpus pubescent posteriorly, with clusters of simple setae anteriorly and medially, length 0.54 x basis, posterior margin slightly convex; propodus short, length 2.10 x width, subquadrate, minutely chelate, oblique anterodistally, with 7 long pectinate setae, length 0.50 x carpus, palm obtuse with 1 simple setule; dactylus small, acute, fitting palm. Pereopod 3 (Fig. 5C), coxa similar to that of gnathopod 2 but slightly more curved, width 0.42 x length; basis subrectangular, with 3 simple setae posterodistally; ischium short, length 0.31 x basis, with 8 simple setae posteriorly; merus length 1.50 x carpus, produced anterodistally, with long simple setae posteriorly; propodus subrectangular, slightly longer than carpus, with a row of 7 spines posteriorly; dactylus falcate, length 0.43 x propodus. Pereopod 4 similar to pereopod 3 except coxa (Fig. 5D) broadened, posterior margin excavate, posterodistal lobe produced, truncate, corner rounded. Pereopod 5 (Fig. 5E), coxa large, rounded quadrate, bilobate, width 1.12 x length; basis subcircular, length 0.98 x width, posteriorly expanded, margin weakly serrate, posteroventral lobe broadly rounded, width subequal to length, with a row of spines along anterior margin; merus expanded posteriorly, anterior margin with 5 simple setae and 3 spines, posterior margin with 5 simple setae; carpus length 0.41 x merus, anterior margin with 6 spines, posterior margin with 2 spines distally; propodus rectangular, length 1.75 x carpus, anterior margin with 5 spines; dactylus falcate, length 0.43 x propodus. Pereopod 6 (Fig. 5F), coxa slightly larger than coxa 7, bilobate, anterior lobe small, posterior lobe roundly produced ventrally; basis narrowly subovate, with a row of spines on distal half of anterior margin, posterior margin weakly serrate, posteroventral lobe narrowly rounded; merus expanded posteriorly, anterior margin with 4 long simple setae and 5 small spines, posterior margin with 2 spines and 2 simple setae; carpus length 0.86 x merus, anterior margin with 3 spines and 4 spines distally, posterior margin with 2 spines distally; propodus rectangular, length 1.33 x carpus, anterior margin with 3 clusters of 2 spines; dactylus falcate, length 0.42 x propodus. Pereopod 7 (Fig. 5G) similar to pereopod 6, but coxa subtriangular; basis much broader than that of pereopod 6, posterior margin broadly expanded, merus expanded. Uropod 1 (Fig. 6A), peduncle subrectangular, length 1.33 x outer ramus, with row of spines on dorsolateral and dorsomedial margins, and 2 apicolateral spines dorsodistally; rami lanceolate; outer ramus subequal in length to inner one, dorsolateral margin with 3 spines; inner ramus with 3 dorsolateral and 1 medial spines. Uropod 2 (Fig. 6B), peduncle slightly longer than outer ramus, with 3 dorsolateral and 2 medial spines; rami lanceolate; outer ramus slightly longer than inner one, with 3 dorsolateral spines; inner ramus with a row of 6 dorsolateral spines. Uropod 3 (Fig. 6C) stout, peduncle short, slightly shorter than outer ramus, with 2 groups of 3 laterodistal spines, medial margin with 4 simple setae and 3 spines; outer ramus biarticulate, length 1.16 x inner ramus, proximal article with 7 long medial plumose setae and 1 spine along inner margin, outer margin with 3 spines; distal article short, length 0.22 x proximal one; inner ramus not reaching base of distal article of outer ramus, outer margin with 8 long plumose setae, inner margin with 2 spines and 1 plumose seta. Telson (Fig. 6D) longer than broad, length 1.55 x width, cleft 62% of its length, each lobe with a pair of simple or bifid setae and 2 spines dorsolaterally, 1 spine and 1 seta apically. Paratype, adult female. Body (Fig. 3B) about 8.6 mm long; head (Fig. 6E) similar to that of male; coxa 1 less expanded anteriorly than that of male; urosomite 1 with moderate dorsal elevation and microserrate distal margin. Antenna 1 (Fig. 6G) stout, similar to that of male; peduncular article 1 with 5 penicillate setae ventrally; flagellum 11-articulate. Antenna 2 (Fig. 6H) callynophore slightly smaller, slender, much shorter than male, peduncular articles 3���5 narrow and elongate, article 5 without expansion and more setose than in male; flagellum 11-articulate, article 1 not elongated as in male. Uropod 3 (Fig. 6I) similar to that of male, rami less setose and inner ramus shorter. Depth range. 60���100 m Remarks. The genus Microlysias Stebbing, 1918 is similar to the genera Orchomene Boeck, 1871 and Lysianella G.O. Sars, 1882 in having the following characteristics: 1) mouthparts forming quadrate bundle; 2) coxa 1 large and visible, not tapering; 3) gnathopod 1 short, strongly subchelate; 4) gnathopod 2 minutely chelate; and 5) uropod 3, outer ramus 2-articulate (Barnard & Karaman, 1991). However, Microlysias is easily distinguished from those two genera by having a swollen peduncular article 5 of male antenna 2 (Barnard & Karaman, 1991; Lowry & Kilgallen, 2014) and an elongated article 1 of the mandibular palp. The mandibular molar of the genus Orchomenella is button-shaped (truncated cylinder) and armed with denticles and cusps but without pubescence, the article 1 of the mandibular palp is short and the outer plate of the maxilliped has 2 strong apical spines (Barnard & Karaman, 1991). These characteristics are distinctly different from the genus Microlysias. Among the species of Orchomenella, O. japonica Gurjanova, 1962 is similar to Microlysias species in possessing a swollen peduncular article 5 of antenna 2 in male. However, O. japonica is distinguished from species of Microlysias by a combination of the following features (Microlysias species characters in parentheses): 1) molar button-shaped (vs. elongate and forms a setose ridge); 2) mandibular palp with very short article 1 (vs. elongated article 1). These characters exclude O. japonica from Microlysias and therefore it should remain in the genus Orchomenella. Microlysias rectangulatus sp. nov. is similar to M. xenokeras Stebbing, 1918, M. soela Lowry & Kilgallen, 2014, M. triangulus sp. nov. (this paper) and Orchomenella japonica Gurjanova, 1962. However, M. rectangulatus differs from those species in the following characters: 1) eyes ovate and smaller (vs. irregularly subrectangular, very large, covering most of head in M. soela, reniform in O. japonica); 2) antenna 2, peduncular article 5 subrectangular, length 1.45 x width (vs. length=width in M. xenokeras and length 0.95 x width in M. soela); 3) mandibular palp, article 1 very long, length 0.98 x article 3 (vs. short, length 0.23 x article 3 in O. japonica, 0.61 x article 3 in M. triangulus, 0.70 x article 3 in M. xenokeras and 0.60 x article 3 in M. soela); 4) gnathopod 2, propodus subovate, length 2.1 x width (vs. slender, length 2.90 x width in M. xenokeras, 2.50 x width in M. soela and 2.43 x width in M. triangulus); 5) epimeron 2���3 and urosome 1, posterior margin microserrate (vs. smooth in all the other species); and 6) pereopod 7, merus expanded (vs. not expanded in all the other species). The feeding behavior of Microlysias had been unknown, however we discovered the new species scavenging on flat fish caught in the net (Fig. 2). This discovery leads us to report M. rectangulatus as a carnivorous and likely opportunistic, scavenging species. Distribution. Korea (Goseong-gun)., Published as part of Heo, Jun-Haeng, Hendrycks, Ed A. & Kim, Young-Hyo, 2020, Two new species of the genus Microlysias (Crustacea, Amphipoda, Tryphosidae) from Korean Waters, pp. 543-556 in Zootaxa 4759 (4) on pages 544-550, DOI: 10.11646/zootaxa.4759.4.5, http://zenodo.org/record/3741063, {"references":["Stebbing, T. R. R. (1918) Some Crustacea of Natal. Annals of the Durban Museum, 2, 47 - 75, pls. 8 - 12.","Barnard, J. L. & Karaman, G. S. (1991) The families and genera of marine gammaridean Amphipoda (except marine gammaroids). Records of The Australian Museum, Supplement 13, 1 - 866. https: // doi. org / 10.3853 / j. 0812 - 7387.13.1991.367","Lowry, J. K. & Kilgallen, N. M. (2014) New tryphosine amphipods from Australian waters (Crustacea, Amphipoda, Lysianassoidea, Lysianassidae, Tryphosinae). Zootaxa, 3844 (1), 1 - 64. https: // doi. org / 10.11646 / zootaxa. 3844.1.1","Gurjanova, E. F. (1962) Amphipods of the northern part of the Pacific Ocean (Amphipoda-Gammaridea). Part 1. Akademiya Nauk SSSR, Opredeliteli po Faune SSSR, 74, 1 - 440."]}

Key to species of Microlysias 1. Antenna 2 male, peduncular article 5 subquadrate, enlarged; gnathopod 1 length M. triangulus sp. nov. 2. Eyes very large, irregularly subrectangular, occupying most of head; maxilla 1, inner plate with a slender spine projection apically; maxilla 2 plates stout.................................................. M. soela Lowry & Kilgallen, 2014 - Eyes ovoid, medium sized, not occupying most of head; maxilla 1, inner plate lacking a slender spine projection apically; maxilla 2 plates slender, of normal size....................................................................... 3 3. Male antenna 2, peduncular article 5, length=width; gnathopod 2, propodus very slender and curved, length 2.9 x width; pereopod 7, merus narrow; epimeral plates 2���3, posterior margins smooth; mandibular palp, article 1, length about 0.7 x article 3............................................................................... M. xenokeras Stebbing, 1918 - Male antenna 2, peduncular article 5, length 1.45 x width; gnathopod 2, propodus subquadrate, straight, length 2.1 x width; pereopod 7, merus expanded; epimeral plates 2���3, posterior margins microserrate; mandibular palp, article 1, length subequal to article 3........................................................................ M. rectangulatus sp. nov., Published as part of Heo, Jun-Haeng, Hendrycks, Ed A. & Kim, Young-Hyo, 2020, Two new species of the genus Microlysias (Crustacea, Amphipoda, Tryphosidae) from Korean Waters, pp. 543-556 in Zootaxa 4759 (4) on page 556, DOI: 10.11646/zootaxa.4759.4.5, http://zenodo.org/record/3741063, {"references":["Lowry, J. K. & Kilgallen, N. M. (2014) New tryphosine amphipods from Australian waters (Crustacea, Amphipoda, Lysianassoidea, Lysianassidae, Tryphosinae). Zootaxa, 3844 (1), 1 - 64. https: // doi. org / 10.11646 / zootaxa. 3844.1.1","Stebbing, T. R. R. (1918) Some Crustacea of Natal. Annals of the Durban Museum, 2, 47 - 75, pls. 8 - 12."]}

The complete mitochondrial genome of the deep sea amphipod Eurythenes magellanicus was determined in this paper. This molecular was 14,988 bp in length, and contained the typical 13 protein coding ...

Thurston, Michael H., Horton, Tammy (2020): Claudedebeella, a replacement name for Falklandia De Broyer, 1985 (Crustacea, Amphipoda, Lysianassoidea, Tryphosidae), preoccupied by Falklandia Forster & Platnick, 1985 (Arachnida, Araneae). Zootaxa 4750 (3): 437-438, DOI: https://doi.org/10.11646/zootaxa.4750.3.10

Claudedebeella reducta (Schellenberg, 1931) Orchomenopsis reducta Schellenberg, 1931: 49 51, fig. 26. Orchomenella reducta.��� Ruffo, 1949: 11, fig. 1.��� Barnard, 1958: 97. Orchomene reducta.��� Barnard, 1964: 89 (in key).��� Lowry & Bullock, 1976: 100.��� Shulenberger & Barnard, 1976: 248. Falklandia reducta.��� De Broyer, 1985: 303 312, figs 1 6.��� Barnard & Karaman, 1991: 487.��� De Broyer & Jażdżewski, 1993: 68.��� De Broyer & Rauschert, 1999: 285. ��� De Broyer et al., 2007: 138.��� Havermans et al., 2010: 204 207.��� Havermans et al., 2011: 233, 235.��� Lowry & Kilgallen, 2014: 303. Remarks. Despite multiple literature records, knowledge of the species is based on only five specimens, three from the type locality, 52��29���S 60��36���W, just south-west of the Falkland Islands at a depth of 197 metres (Schellenberg, 1931), one from 70��15���S 85��06���W, in the Bellingshausen Sea at a depth of 569 metres (Ruffo, 1949) and one from 61��23���S 55��26���W, in the Scotia Sea at a depth of 285 metres (Havermans et al., 2011)., Published as part of Thurston, Michael H. & Horton, Tammy, 2020, Claudedebeella, a replacement name for Falklandia De Broyer, 1985 (Crustacea, Amphipoda, Lysianassoidea, Tryphosidae), preoccupied by Falklandia Forster & Platnick, 1985 (Arachnida, Araneae), pp. 437-438 in Zootaxa 4750 (3) on page 437, DOI: 10.11646/zootaxa.4750.3.10, http://zenodo.org/record/3707448, {"references":["Schellenberg, A. (1931) Gammariden und caprelliden des Magellangebietes, Sudgeorgiens und der Westantarkis. Further zoological results of the Swedish Antarctic Expedition 1901 ̶ 1903, 2 (6), 1 290.","Ruffo, S. (1949) Amphipodes (II). Expedition Antarctique Belge. Resultats du voyage de la Belgica en 1897 1899. Rapports Scientifiques, Zoologie, 1 58.","Barnard, J. L. (1958) Index to the families, genera, and species of the gammaridean Amphipoda (Crustacea). Allan Hancock Foundation Publications, Occasional Paper, 19, 1 - 145.","Barnard, J. L. (1964) Marine Amphipoda of Bahia de San Quintin, Baja California. Pacific Naturalist, 4 (3), 55 139.","Lowry, J. K. & Bullock, S. (1976) Catalogue of the marine gammaridean Amphipoda of the Southern Ocean. Bulletin of the Royal Society of New Zealand, 16, 1 187.","Shulenberger, E. & Barnard, J. L. (1976) Amphipods from an abyssal trap set in the North Pacific Gyre. Crustaceana, 31 (3), 241 - 258. https: // doi. org / 10.1163 / 156854076 X 00035","De Broyer, C. (1985) Description de Falklandia gen. n. de l'Ocean Austral et definition des Lysianassoidea uristidiens (Crustacea, Amphipoda). Zoologica Scripta, 14 (4), 303 312. https: // doi. org / 10.1111 / j. 1463 - 6409.1985. tb 00200. x","Barnard, J. L. & Karaman, G. S. (1991) The families and genera of marine gammaridean Amphipoda (except marine gamma- roids). Records of the Australian Museum, Supplement 13, 1 - 866. https: // doi. org / 10.3853 / j. 0812 - 7387.13.1991.367","De Broyer, C. & Jazdzewski, K. (1993) Contribution to the marine biodiversity inventory. A checklist of the Amphipoda of the Southern Ocean. Documents de travail de l'Insitut Royal des Sciences Naturelles de Belgique, 73, 1 154.","De Broyer, C. & Rauschert, M. (1999) Faunal diversity of the benthic amphipods (Crustacea) of the Magellan region as compared to the Antarctic (preliminary results). Scientia Marina, 63 (Supplement 1), 281 293. https: // doi. org / 10.3989 / scimar. 1999.63 s 1281","De Broyer, C., Lowry, J., Jazdzewski, K. & Robert, H. (2007) Catalogue of the Gammaridean and Corophiidean Amphipoda (Crustacea) of the Southern Ocean with distribution and ecological data. In: De Broyer, C. (Ed.), Census of Antarctic Marine Life: Synopsis of the Amphipoda of the Southern Ocean. Vol. 1. Bulletin de l'Institut Royal des Sciences Naturelles de Belgique, Biologie, 77 (Supplement 1), pp. 1 - 325.","Havermans, C., Nagy, Z. T., Sont, G., De Broyer, C. & Martin, P. (2010) Incongruence between molecular phylogeny and morphological classification in amphipod crustaceans: A case study of Antarctic lysianassoids. Molecular Phylogenetics and Evolution, 55, 202 209. https: // doi. org / 10.1016 / j. ympev. 2009.10.025","Havermans, C., Nagy, Z. T., Sont, G., De Broyer, C. & Martin, P. (2011) DNA barcoding reveals new insights into the diversity of Orchomene sensu lato (Crustacea: Amphipoda: Lysianassoidea). Deep-Sea Research II, 58, 230 241. https: // doi. org / 10.1016 / j. dsr 2.2010.09.028","Lowry J. K. & Kilgallen N. M. (2014) A revision of the lysianassid genus Waldeckia with the description of four new species (Crustacea, Amphipoda, Lysianassidae, Waldeckiinae subfam. nov.). Zootaxa, 3784 (4), 301 304. https: // doi. org / 10.11646 / zootaxa. 3784.4.1"]}

Eurythenes plasticus sp. nov. Weston (Figs. 4���8) Material Examined. HOLOTYPE: Mature female, USNM 1615729, body length 48.1 mm. PARATYPES: Mature male, USNM 1615732, GenBank (16S MT 021437), (COI MT 038070), body length 47.6 mm, Mariana Trench, Pacific Ocean (11.5911N, 144.84730E), cruise FK 141109, station LH14, depth 6010 m. Immature female, USNM 1615733 GenBank (16S MT 021438), (COI MT 038071), body length 38.6 mm, Mariana Trench, Pacific Ocean (11.6071N, 144.8331E), cruise FK 141109, station LH15, depth 6142 m. Juvenile, USNM XXXX3, body length 15.6 mm, same collection location as type locality . PARAGENETYPE: Juvenile, GenBank (16S MT 021439), (COI MT 038072), body length 15.1 mm, same collection location as type locality. NON-TYPE SPECIMENS: Three juveniles, body lengths 12.5, 13.5 & 15.7 mm, same collection location as type locality, USNM 1615731. Type Locality. Mariana Trench, Pacific Ocean (12.64065N, 144.73796E), cruise FK141109, station WT02, depth 6865 m. Etymology. The species names, plasticus, stems from Latin for plastic. This name speaks to the ubiquity of plastic pollution present in our oceans. Diagnosis. Lateral cephalic lobe strongly produced, slightly triangular. Article 2 of mandibular palp narrow. Maxilliped inner plate with three to four apical protruding nodular setae. Gnathopod 1 subchelate, basis narrow (2.9x as long as wide), palm not protruding and weakly convex. Gnathopod 2 subchelate, coxa broad ventrally and weakly curved, palm convex. Pereopods 3 to 7 dactyli short. Pereopod 5 coxa bilobate and posterior lobe larger than anterior lobe. Epimeron 3 posteroventral corner subquadrate without small posteroventral tooth. Uropod 1 and 2 rami margins with spine-like setae. Dorsal carination with increasing degree on epimeron 1-3 and urosomite 1. Description, based on holotype, female, USNM 1615729. BODY (Figs. 4, 5, 6): surface smooth, without setae; urosomite 3 with an anterodorsal depression. Oostegites present on gnathopod 2 to pereopod 5, elongate but lacking setae. Coxa gills present on gnathopod 2 to pereopod 7. Colour pattern at time of recovery unknown. HEAD (Fig. 5): rostrum absent; ventral corner of eye rounded and obliquely pointing backwards (Fig. 5C). Antenna 1 short, 0.1x as long as body length; accessory flagellum 12-articulate; primary flagellum 28-articulate; callynophore well-developed; calceoli absent (Fig. 5A). Antenna 2 medium length, 0.3x as long as body, 1.8x as long as antenna 1; flagellum 59-articulate; calceoli absent (Fig. 5B). MOUTHPART BUNDLE (Fig. 5): Mandible left lacinia mobilis a long slender distally cuspidate robust seta; setal row left with 13 short, slender, robust setae; molar large, setose, vestigial distal triturating patch; palp article length ratio 1: 3.2: 2.6, article 2 posteriorly not expanded and distally not tapering, 3.4x as long as wide; article 3 blade-like (Fig. 5I). Maxilla 1 inner plate with nine apical and sub-apical plumose setae; outer plate with an 8/3 setal crown arrangement; palp longer than outer plate, 2-articulate, seven sub-apical and apical setae with one being a flag seta (Fig. 5H). Maxilla 2 inner and outer plates broad, inner plate 0.6x shorter than outer plate (Fig. 5G). Maxilliped inner plate large, sub-rectangular, four apical protruding nodular setae; outer plate subovate, with 12 apical setose setae; palp large and well-developed; dactylus well-developed, unguis present, six small apical setae (Fig. 5D, F). PEREON (Figs. 6, 7): Gnathopod 1 coxa very weakly anteriorly concave, anteroventral margin with setae; palm crenulate, 0.4x as long as width of propodus, defined by one robust seta at base of palm and another robust seta at end of palm that is 2.6x longer; dactylus curved posteriorly, one long anterodistal seta, unguis present (Fig. 6A, B). Gnathopod 2 subchelate, coxa obovate, broad ventrally and weakly curved; propodus elongate, not expanded distally, 6.1x as long as wide; propodus 2.7x as long as wide, moderately expanded distally; palm crenulate, distal end defined by three robust setae; dactylus not reaching palmar corner, curved posteriorly, unguis present, one long anterodistal seta (Fig. 6A, B). Pereopod 3 coxa sub-rectangular, 2.0x as long as wide, setae on surface of coxa and along ventral and posterior margins; basis weakly expanded posteriorly, 2.7x as long as wide; merus expanded anteriorly, tuft of setae on anteroventral corner; propodus 4.8x as long as wide; dactylus short, 0.4x as long as propodus, unguis present (Fig. 6C). Pereopod 4 coxa broad, 1.2x as long as wide, 1.1x length of coxa 3, junction between anterior and ventral border bluntly angular (sub-rectangular), ventral border straight, posteroventral border straight and weakly oblique; leg almost identical with pereopod 3 (Fig. 6D). Pereopod 5 coxa bilobate, posterior lobe 1.3x longer and 1.6x wider than anterior lobe, ventral border of posterior lobe sub-triangular; basis expanded posteriorly, posterior margin smooth; merus broadly expanded posteriorly, 1.5x as long as wide, curved posterior margin; propodus slender, 6.2x as long as wide, seven groups of robust setae on the anterior margin; dactylus short, 0.4x as long as propodus, unguis present (Fig. 7A). Pereopod 6 coxa subquadrate, posterior margin weakly bilobate or weakly concave; basis expanded posteriorly, posterior margin distinctly crenate; merus broadly expanded posteriorly, 1.7x as long as wide, convex posterior margin; propodus slender, 5.9x as long as wide, eight groups of robust setae on the anterior margin; dactylus slender, short, 0.3x as long as propodus, unguis present (Fig. 7B). Pereopod 7 coxa sub-rectangular; basis with posterior border crenulate and strongly expanded, distal lobe moderately protruding; merus broadly expanded posteriorly, 1.6x as long as wide, convex posterior margin; propodus with normal stoutness, 5.6x as long as wide, eight groups of robust setae on the anterior margin; dactylus slender, short, 0.3x as long as propodus, unguis present (Fig. 7C). PLEON AND UROSOME (Figs. 7, 8): Epimeron 1 anteroventral corner rounded with long slender setae; posteroventral corner produced into a small tooth. Epimeron 2 anteroventral margin lined with short fine setae; posteroventral corner produced into a strong tooth. Epimeron 3 ventral margin lined with long fine setae, weakly curved (Fig. 7D). Urosomite 1 with anterodorsal notch (Fig. 7D). Uropod 1 peduncle with one apicomedial setae; inner ramus subequal in length to outer ramus; outer ramus 0.85x as long as peduncle; outer ramus with 18 lateral and eight medial spine-like setae; inner ramus with 20 lateral and 11 medial spine-like setae (Fig. 8A). Uropod 2 peduncle with one apicomedial setae; inner ramus subequal in length (0.9x) to outer ramus; outer ramus subequal in length to peduncle outer ramus with 20 lateral and three medial spine-like setae; inner ramus with seven lateral and 16 medial spine-like setae (Fig. 8B). Uropod 3 inner ramus subequal in length to article 1 of outer ramus; article 2 of outer rami short, 0.05x length of article 1; setae of distolateral angle of peduncle of normal length and stoutness; medial margins of both rami with plumose setae (Fig. 8C). Telson 70% cleft, pair of apical setae on each lobe parallel with beginning of cleft, distal margin with a single apical seta on right lobe, distal end of left lob missing (Fig. 8D). Variations. As with other species of Eurythenes, there appears to be very little sexual dimorphism. In part, this could be limited to having a single male specimen. The mature male paratype (USNM 1615732) has calceoli present on both antenna 1 and antenna 2. Both antennae are shorter than the holotype with antenna 1 accessory flagellum being 10-articulate, antenna 1 25-articulate, and antenna 2 54-articulate. Additionally, the maxilliped inner plate of the male paratype has three apical protruding nodular setae, specifically lacking the third setae present on the holotype (Fig. 5F). There were differences present in the juvenile paratype (USNM 1615730) that included typical cohort differences among Eurythenes, such as fewer setae on pereopods and uropods and reduced articulation on antennae (antenna 1 accessory flagellum 7-articulate, antenna 1 15-articulate, and antenna 2 38-articulate). In addition, the juvenile paratype had more pronounced and raised dorsal carination than on the adults (Fig. 7E). This difference was present among all the juvenile specimens observed. Differential Diagnosis. As highlighted in d���Udekem d���Acoz & Havermans (2015), the morphological characteristics that separate and define the species within the gryllus -complex are hard to observe and should be used with caution. Eurythenes plasticus sp. nov. is a member of the gryllus -complex morphologically and genetically. Nevertheless, there is a combination of characters that are unique to E. plasticus sp. nov. and allow it to be distinguished from the morphologically similar species E. andhakarae, E. magellanicus, and E. aequilatus. The most distinctive characteristics are the robust, spine-like setae on rami of uropod 1 and 2 (Fig. 8A, B) and the lobes of pereopod 5 coxa (Fig. 7A), here being unequal, which is novel within Eurythenes. Eurythenes plasticus sp. nov. can be differentiated from E. andhakarae with article 2 of the mandible palp being narrow (instead of expanded), four protruding nodular spines on the inner plate of the maxilliped (versus three non-protruding), and straight ventral border of coxa 4 (opposed to curved). Eurythenes plasticus sp. nov. can be separated from E. magellanicus with a long gnathopod 1 palm (instead of short), a straight ventral border of coxa 4 (opposed to curved), a subquadrate posteroventral corner in epimeron 3 (instead of bearing a small tooth), and the rami of uropod 1 and 2 being subequal (opposed to uropod 2 outer ramus being shorter than inner ramus and uropod 1 outer ramus being longer than inner ramus). Eurythenes plasticus sp. nov. can also be distinguished from E. aequilatus by its eyes with a variable width (opposed to constant width), the outer plate of maxilla 1 with 8/3 crown arrangement (instead of 9/3 arrangement), and a long gnathopod 1 palm (instead of short). Habitat, Distribution and Biology. Eurythenes plasticus sp. nov. was collected from the upper hadal depths of the Mariana Trench, between 6010 and 6949 m. Similar to sister species within the genus, E. plasticus sp. nov. is a benthic scavenger, as individuals of multiple cohorts entered the baited traps. Eurythenes plasticus sp. nov. is a member of a wider scavenging amphipod community comprised of A. gigantea, Bathycallisoma schellenbergi (Birstein & Vinogradov, 1958), Hirondellea dubia Dahl, 1959, H. gigas, Paralicella caperesca Shulenberger & Barnard, 1976, Paralicella tenuipe s Chevreux, 1908, and Valettietta anacantha (Birstein & Vinogradov, 1963), which were concurrently recovered in the traps (data unpublished). Discussion The salient finding of this study is the paired molecular and morphological identification approaches provided congruent evidence that E. plasticus sp. nov. represents an undescribed species within Eurythenes. Further, as a scavenger at upper hadal depths (6010 ��� 6949 m) in the Mariana Trench, E. plasticus sp. nov. is not exempt from ingesting microplastics that are bioavailable within the hadal zone. In comparison to described Eurythenes species, E. plasticus sp. nov. was placed as part of the gryllus -complex and most closely related to the abyssal E. magellanicus (Fig. 2). The bPTP analysis of COI and both K2P analyses delineated E. plasticus sp. nov. to be a distinctive lineage, and these methods aligned with previous studies that detected cryptic speciation within the gryllus -complex (Havermans et al. 2013; Eustace et al. 2016; Narahara-Nakano et al. 2017). The 16S phylogeny specifically showed E. plasticus sp. nov. to be nearly identical to Eg7 (Fig. 2A; France & Kocher 1996; Havermans et al. 2013). This Eurythenes sp. was a singleton recovered from abyssal depths at the Horizon Guyot seamount, Pacific Ocean, and it was collected along with another Eurythenes sp. from the divergent Eg9 clade (Havermans et al. 2013). Confidence in the identification of Eg7 would be further strengthened with additional genetic or morphological data. The morphological variation seen in E. plasticus sp. nov., such as an uneven coxa 5 lobe and lack of a tooth on the posteroventral corner of epimeron 3, supported the phylogenetic evidence as an undescribed lineage. Consistent with previous studies, these morphological characteristics should be used with caution, as some are difficult to discern objectively. Additional specimens, like from the Eg7 clade, may reveal phenotypic plasticity in the characteristics observed in this morphological study (d���Udekem d���Acoz & Havermans 2015). Continued application of a combined molecular and morphological approaches in future studies is likely to reveal further species diversity within the gryllus -complex. The discovery of E. plasticus sp. nov. continues to align with the pattern Eurythenes that the geographic and bathymetric species distributions are complex (Havermans 2016). With the Eg7 singleton, the geographic range of E. plasticus sp. nov. thus far appears to be restricted to the Central Pacific Ocean. Across that ocean basin, E. plasticus sp. nov. has broad bathymetric range, ~ 3000 m. While it is common among Eurythenes to be found only in a single ocean basin and have a wide vertical distribution (Eustace et al. 2016; Havermans 2016), it is less common to span across the abyssal and hadal zones. Although, this is not unique, as it has been documented in other amphipods, such as A. gigantea (Jamieson et al. 2013). A species needs to be able to cope at the cellular, reproductive, and physiological levels in both the stable abyssal (Smith et al. 2008) and the dynamic hadal environments (Jamieson 2015; Downing et al. 2018). Yet, it was curious that during the present study, E. plasticus sp. nov. was only collected from upper hadal depths, despite amphipods being captured at shallower and deeper depths (43 additional deployments 4506 to 10545 m; data unpublished). This highlights that the distribution of E. plasticus sp. nov. is a patchwork. Further work and sampling will be required to understand the conditions that support the presence of this species. The finding of a microplastic fibre in the hindgut of a juvenile was not unexpected. Deep-sea scavenging amphipods, as an adaption to their food limited environment, indiscriminately consume carrion (Blankenship & Levin 2007) and are known to inadvertently ingest microfibres present in the carrion and sediment (Jamieson et al. 2019). The detection of a microplastic adds to the number of hadal scavenging amphipods, including adult specimens of H. gigas from the Mariana Trench and Eurythenes sp. ���hadal��� the Peru-Chile Trench (Jamieson et al. 2019), which have been found to have consumed plastic microfibers. Microplastic consumption by a juvenile indicates that scavenging amphipods are potentially ingesting microplastics throughout their life, which could pose acute and chronic health effects. While the ecotoxicological impacts of microplastic exposure has yet to be investigated on deep-sea amphipods, early work on other Malacostraca indicates that the ingestion of polypropylene fibres by the sand crab, Emerita analoga, increases adult mortality and decreases in retention of egg clutches (Horn et al. 2019). This study adds to the growing body of literature on marine organisms ingesting plastic and microfibers (Besseling et al. 2015; Lusher et al. 2015; Bellas et al. 2016; Alomar & Deudero 2017). The microplastic found in the hindgut of E. plasticus sp. nov. was most similar to PET, which is one of the top five most prevalent synthetic plastic polymers produced and discarded globally (Geyer et al. 2017). Without substantial global changes to the life cycle of plastic, from reducing the rate of plastic production to improving waste management (Forrest et al. 2019), plastics and microfibres will continue to be transported to the deep sea and be ubiquitous in the hadal food chain for the foreseeable future., Published as part of Weston, Johanna N. J., Carrillo-Barragan, Priscilla, Linley, Thomas D., Reid, William D. K. & Jamieson, Alan J., 2020, New species of Eurythenes from hadal depths of the Mariana Trench, Pacific Ocean (Crustacea: Amphipoda), pp. 163-181 in Zootaxa 4748 (1) on pages 169-177, DOI: 10.11646/zootaxa.4748.1.9, http://zenodo.org/record/3697667, {"references":["d'Udekem d'Acoz, C. & Havermans, C. (2015) Contribution to the systematics of the genus Eurythenes S. I. Smith in Scudder, 1882 (Crustacea: Amphipoda: Lysianassoidea: Eurytheneidae). Zootaxa, 3971 (1), 1 - 80. https: // doi. org / 10.11646 / zootaxa. 3971.1.1","Havermans, C., Sonet, G., d'Udekem d'Acoz, C., Nagy, Z. T., Martin, P., Brix, S., Riehl, T., Agrawal, S. & Held, C. (2013) Genetic and morphological divergences in the cosmopolitan deep-sea amphipod Eurythenes gryllus reveal a diverse abyss and bipolar species. Public Library of Science One, 8 (9), e 74218. https: // doi. org / 10.1371 / journal. pone. 0074218","Eustace, R. M., Kilgallen, N. M., Ritchie, H., Piertney, S. B. & Jamieson, A. J. (2016) Morphological and ontogenetic stratification of abyssal and hadal Eurythenes gryllus sensu lato (Amphipoda: Lysianassidae) from the Peru-Chile Trench. Deep Sea Research I: Oceanographic Research Papers, 109, 91 - 98. https: // doi. org / 10.1016 / j. dsr. 2015.11.005","France, S. C. & Kocher, T. D. (1996) Geographic and bathymetric patterns of mitochondrial 16 S rRNA sequence divergence amount deep-sea amphipods, Eurythenes gryllus. Marine Biology, 126 (4), 633 - 643.","Havermans, C. (2016) Have we so far only seen the tip of the iceberg? Exploring species diversity and distribution of the giant amphipod Eurythenes. Biodiversity, 17 (1 - 2), 12 - 25. https: // doi. org / 10.1080 / 14888386.2016.1172257","Jamieson, A. J., Lacey, N. C., Lorz, A. N., Rowden, A. A. & Piertney S. B. (2013) The supergiant amphipod Alicella gigantea (Crustacea: Alicellidae) from hadal depths in the Kermadec Trench, SW Pacific Ocean. Deep Sea Research II: Topical Studies in Oceanography, 92, 107 - 113. https: // doi. org / 10.1016 / j. dsr 2.2012.12.002","Smith, C. R., De Leo, F. C., Bernardino, A. F., Sweetman, A. K. & Arbizu, P. M. (2008) Abyssal food limitation, ecosystem structure and climate change. Trends in Ecology & Evolution, 23 (9), 518 - 528. https: // doi. org / 10.1016 / j. tree. 2008.05.002","Jamieson, A. J. (2015) The hadal zone: Life in the deepest oceans, 1 st ed. Cambridge University Press, Cambridge, UK.","Downing, A. B., Wallace, G. T. & Yancey, P. H. (2018) Organic osmolytes of amphipods from littoral to hadal zones: Increases with depth in trimethylamine N-oxide, scyllo - inositol and other potential pressure counteractants. DeepSea Research Part I: Oceanographic Research Papers, 138, 1 - 10. https: // doi. org / 10.1016 / j. dsr. 2018.05.008","Blankenship, L. E. & Levin, L. A. (2007) Extreme food webs: Foraging strategies and diets of scavenging amphipods from the ocean's deepest 5 kilometers. Limnology and Oceanography, 52 (4), 1685 - 1697.","Jamieson, A. J., Brooks, L. S. R., Reid, W. D. K., Piertney, S. B., Narayanaswamy, B. E., & Linley, T. D. (2019) Microplastics and synthetic particles ingested by deep-sea amphipods in six of the deepest marine ecosystems on Earth. Royal Society Open Science, 6 (2), 180667. http: // dx. doi. org / 10.1098 / rsos. 180667","Horn, D., Granek, E. F. & Steele, C. L. (2019) Effects of environmentally relevant concentrations of microplastic fibers on Pacific mole crab (Emerita analoga) mortality and reproduction. Limnology and Oceanography Letters. https: // doi. org / 10.1002 / lol 2.10137","Besseling, E., Foekema, E. M., Van Franeker, J. A., Leopold, M. F., Kuhn, S., Bravo Rebolledo, E. L., Hesse, E., Mielke, L. J. I. J., Ijzer, J., Kamminga, P. & Koelmans, A. A. (2015) Microplastic in a macro filter feeder: Humpback whale Megaptera no- vaeangliae. Marine Pollution Bulletin, 95 (1), 248 - 252. https: // doi. org / 10.1016 / j. marpolbul. 2015.04.007","Bellas, J., Martinez-Armental, J., Martinez-Camara, A., Besada, V. & Martinez-Gomez, C. (2016) Ingestion of microplastics by demersal fish from the Spanish Atlantic and Mediterranean coasts. Marine Pollution Bulletin, 109 (1), 55 - 60. https: // doi. org / 10.1016 / j. marpolbul. 2016.06.026","Alomar, C. & Deudero, S. (2017) Evidence of microplastic ingestion in the shark Galeus melastomus Rafinesque, 1810 in the continental shelf off the western Mediterranean Sea. Environmental Pollution, 223, 223 - 229. https: // doi. org / 10.1016 / j. envpol. 2017.01.015","Geyer, R., Jambeck, J. R. & Lavender Law, K. (2017) Production, use, and fate of all plastic ever made. Science Advances, 3 (7), e 1700782. https: // doi. org / 10.1126 / sciadv. 1700782","Forrest, A., Giacovazzi, L., Dunlop, S., Reisser, J., Tickler, D., Jamieson, A. J. & Meeuwig, J. J. (2019) Eliminating plastic pollution: How a voluntary contribution from industry will drive the circular plastics economy. Frontiers in Marine Science, 6: 627. https: // doi. org / 10.3389 / fmars. 2019.00627"]}

Shoemakerella fissipro sp. nov. Shoemakerella fissipro Ortiz, Capetillo & Winfield, 2018: 599–605, figs. 1–4 [unavailable]. Type material. HOLOTYPE: female with oostegites, 5.3 mm total length, 2 m depth, collected in a spiny lobster puerulus tramp, September 30, 2016, deposited in the National Crustacean Collection of the of Biology Institute, National Autonomous University of Mexico, Mexico City, CNCR 34500. PARATYPE: female with oostegites, 5.4 mm total length, collected together with the holotype, CNCR34501. Diagnosis. Mandible palp article 3 surface finely grooved, without setae or cuticular extrusions, on both margins; article 3 short, 0.7× article 2; propodus on pereopods 3–7 with distal fissure; pereopods 6 and 7 basis posterior margin concave; telson posterior margin rounded. Etymology. The new species is named after the morphological characteristic (fissure) in the distal part of each propodus of the pereopods 3–7. Remarks. A full description and figures of S. fiissipro and list of additional non-type material examined is given by Ortiz et al. (2018).

Ortiz et al. (2018) described a new species of lysianassid amphipod, Shoemakerella fissipro, from Gulf of California, northeastern Pacific Ocean. Although the description and figures presented by Ortiz et al. (2018) fully characterize the new species, the journal issue in which the description appeared was published online only, and the article in which the new name appeared did not include a ZooBank registration number (LSID), required for validation of new names in electronic-only publications (ICZN 2012). As a result, the name Shoemakerella fissipro Ortiz, Capetillo & Winfield, 2018, as published in Cahiers de Biologie Marine 59: 599–605, is not available according the International Code of Zoological Nomenclature (ICZN 1999, 2012). Therefore, the present note serves to validate name Shoemakerella fissipro by fulfilling ICZN conditions for nomenclatural availability.

Ortiz, Manuel, Capetillo, Norberto, Winfield, Ignacio (2020): Validation of Shoemakerella fissipro Ortiz, Capetillo & Winfield, from the Gulf of California, northeastern Pacific Ocean (Amphipoda: Amphilochidea: Lysianassidae). Zootaxa 4728 (1): 150-150, DOI: https://doi.org/10.11646/zootaxa.4728.1.10

Aruga kieppe sp. nov. (Figs 5–8) Material examined. Holotype, female, 7.0 mm. April 2013, Quiepe (Kieppe) Island in Camamu Bay, Bahia (13°50'60''S 38°58'001''W), UERJ 75. Type-locality. Quiepe Island in Camamu Bay, Bahia, Brazil. Etymology. Specific epithet corresponds to the name of the island. That can be Quiepe or Kieppe. Diagnosis. Gnathopod 2, carpus, posterior margin concave and strongly setose. Urosomite 1, dorsal median margin with a dorsal forward turned keel and two lateral carinas. Description. ( Holotype). Head naked. Lateral cephalic rounded. Antenna 1, first peduncular article with plumose setae in dorsal and ventral margins; article 2, 0.3 × article 1 length, with plumose and simple setae in anterodorsal and anteroventral corners; primary flagellum with 10 articles, two fields of callynophore, one strong and another weak, articles with simple setae in corners; accessory flagellum with six articles. Antenna 2, articles 4 and 5 subrectangular, approximately the same length, with simple and plumose setae; peduncle 7-articulate. Mouthparts forming a subquadrate bundle. Epistome and upper lip slightly separate, upper lip dominant, acute distally, ventral margin subquadrate, setose. Mandible, incisor smooth, lacinia mobilis in left mandible, modified a slender seta, simple accessory setae; molar slightly setose; palp 3–articulate, article 2 approximately 2,8 × longer than article 1, with four slender and three pectinate setae; article 3, surface setose, with apical setae. Maxilla 1, inner plate, small row of setae in outer margin, two plumose robust setae in apical margin; outer plate, 11 setalteeth in 5/6 arrangement: ST1–4 and ST6–ST7 2-cuspidate, ST5 3-cuspidate, STA–STD 2-cuspidate (with two cusps medially); palp, 2-articulate, serrate, with two small apical setae. Maxilla 2, plates narrow, inner plate with slender setae in apical margin, outer plate with pectinate setae in lateral margin, slender setae in apical margin. Maxilliped, inner plate, lateral and apical margin with plumose setae, small robust setae in apical margin; outer plate, apical margin slightly serrate and rounded; palp, 4-articulate, article 2 and 3, lateral and apical margins with slender setae, article 2, 1.5 × longer than article 1 approximately, 4.5 × longer than wide, dactylus with small subterminal setae and nail. Pereonites 1–7: without setae. Gnathopod 1, simple, coxa, rounded anteriorly, basis; anterior margin setose, tuft of setae in posteroventral corner; ischium, 0.4 × length of basis, tuft of setae in anteroventral corner, posterior margin setose; merus, subtriangular, posterior margin with row of small setae and tuft of slender setae; carpus, approximately 1.5 × longer than wide, anteroventral and posteroventral corner with setae; propodus, approximately 2.0 × longer than wide, anterior margin with distal setae, posterior margin setose; dactylus, small, 0.6 × length of propodus, small setae in posteroventral corner, with nail, 0.4 × length of dactylus. Gnathopod 2, basis subrectangular, 1.8 × longer than wide; basis long, approximately 8 × longer than wide; ischium, 0.4 × length of basis, tuft of setae in distal surface; merus, posterior margin with row of setae, posteroventral corner with simple setae; carpus, 1.7 × longer than merus, anterior and medial margins with simple setae, posterior margin concave and strongly setose, with thin setae; propodus, margins setose, anteroventral corner with pectinate setae, posteroventral corner denticulated; dactylus, small, approximately 0.1 × length of propodus, with nail. Pereopod 3, coxa subrectangular, 1.4 × longer than wide; basis, 0.6 × the length of coxa, anteroventral corner and posterior margin with simple setae; ischium small, approximately 0.3 × the length of basis, posterior margin with simple setae; merus, 2.7 × longer than wide, expanded anteriorly, one slender seta in anteroventral corner, posterior margin setose; carpus, posterior margin setose; propodus, 3.8 longer than wide, small seta in posterior margin; dactylus, elongated, approximately 0.6 × length of propodus, anterior margin with one plumose seta, with nail. Pereopod 4, coxa, elongated, 1.6 × longer than coxa 5; basis, posteroventral corner with simple setae; ischium, posterior margin with setae; merus, 2.5 × longer than wide, anterior margin with 5 small setae, anteroventral corner and posterior margin with simple setae; carpus, small, approximately 0,3 × of the length ischium, without setae; propodus, anteroventral corner with one setae, posterior margin with setae; dactylus, anterior margin with one plumose setae, with nail, with small setae. Pereopod 5, coxa, subquadrate, anterior margin slightly convex, posterior margin straight; basis, anterior and posterior margins with small setae, anteroventral corner with slender setae; ischium, small, 0.4 × length of merus, one seta with accessory seta in anterior margin and one in anteroventral corner; merus, anterior and posterior margin with setae with accessory setae, posterior margin rounded; carpus, anterior and posterior margin slightly rounded, with setae with accessory setae; propodus, subrectangular, setae with accessory setae in anterior margin, one seta in posterior margin and two in posteroventral corner; dactylus, posterior margin with one plumose seta, with nail. Pereopod 6, coxa, anterior margin slightly concave, posterior margin, slightly rounded; basis, 1.4 × longer than wide, anterior margin slightly convex, with simple setae, posterior margin setose; ischium, setae with accessory setae in anterior margin; merus, anterior margin slightly straight with setae with accessory setae, two setae in posterior margin; carpus, anterior margin with two tufts of setae with accessory setae and one in anteroventral corner, posterior margin with one setae; propodus, subrectangular, approximately the same length of carpus, three tufts of setae with accessory setae in anterior margin and in posteroventral corner; dactylus, 0.6 × the length of propodus, with one plumose setae in posterior margin, with nail. Pereopod 7, coxa, anterior margin straight, posteroventral margin rounded, with simple setae; basis, anterior margin with small setae with accessory setae, posterior margin with simple setae, anteroventral corner elongated, ventral margin concave; ischium, with two setae with accessory setae in anteroventral corner; merus, two setae with accessory setae in anteroventral corner, one in posterior margin and one in posteroventral corner; carpus, 1.4 × longer than carpus of pereopod 6, tufts of setae with accessory setae in anterior margin, one in posterior margin and one tuft in posteroventral corner; propodus, 1.6 × longer than propodus of pereopod 6, with tufts of setae in anterior, posterior and ventral margins; dactylus, 0.4 × the length of propodus, posterior margin with small setae, without nail. Pleonite 1–3 and urosome 1–3 without setae, epimeral plates 1–3, posteroventral margin subquadrate to subacute. Urosomite 1, dorsal median margin with a dorsal forward turned keel and two lateral carinas. Uropod 1, peduncle, approximately the same length of rami, dorsal and ventral margins with thin setae; outer ramus, with nail. Uropod 2, peduncle, posterior margin with one seta; ramus, approximately the same length; inner ramus, tuft of slender setae in posterior margin, with constriction, with one long setae with accessory setae, with nail; outer ramus, with nail. Uropod 3, peduncle, approximately the same length of outer rami; rami with nail; inner ramus 0.7 × the length of outer ramus. Telson, entire, slightly longer than wide, posterior margin convex, with three plumose setae in surface. Remarks: Although Aruga kieppe sp. nov. presents similar characters to the genus Shoemakerella, this species belongs to Aruga by the presence of two fields of callynophore on antenna 1, left mandible with lacinia mobilis like a long slender peg, and especially for presenting maxilla 1, outer plate, setal-teeth STA–D medial margin 2- cuspidate. This species differs mainly from A. holmesi, and A. paracuru sp. nov. by having: coxa 1, anterior margin less expanded anteriorly; epimeral plates 1–3, posteroventral margin subquadrate to subacute; urosomite 1, dorsal margin with a keel and dorsal carinas; telson, apical margin convex. The shape of lateral cephalic lobe, the convex telson and the posterior margin of the epimeral plate 3 are the principal differences between this new species and A. oculata

Shoemakerella ungulata sp. nov. (Figs 14–17) Material examined. Holotype, female, 7.2 mm, April 2013, channel of Maraú River, Camamu Bay, Bahia, Brazil, (13°54'S 32°01'W). 6.5 mm, UFBA 3223. Type-locality. Camamu Bay, Bahia, Brazil. Etymology. The epithet refers to the Latin word ungula, that means a hoof or nail, present in the gnathopod 1 dactylus. Diagnosis. Gnathopod 1, dactylus with a strong nail, 1.4 × longer than dactylus. Gnathopod 2, propodus elongate, 4 × longer than wide and 0.9 × carpus length. Uropod 3, peduncle very elongated (1.3 × longer than outer ramus). Telson strongly emarginated. Description. (Based on holotype). Head longer than deep; lateral cephalic lobe rounded, subacute; rostrum absent; eyes reniform. Antenna 1, peduncle, article 1 robust, dorsal margin convex, ventral margin straight, with three plumose setae; article 2 and 3 similar in length; article 2, anterior margin concave, tuft of setae on anterodorsal and anteroventral corners, article 3, slender setae in anterior margin, callynophore absent; primary flagellum 10-articulate; accessory flagellum 5-articulate, articles 1, 2 and 5, with setae in anterior margin. Antenna 2, article 1–3 subequal in length, article 3, setae in anterior and ventral margin, article 4 × longer than article 3, anterodorsal and posteroventral corners with tufts of setae, posteroventral margin with a small plumose seta, ventral margin with slender setae; article 5 small; flagellum 6-articulate; calceoli and callynophore absent. Mouthparts forming a subquadrate bundle. Epistome and upper lip separate with a slightly notch; epistome slightly concave; upper lip rounded dorsally, anterior margin concave, distal margin with notch, forming a rounded shape, ventral margin concave, anteroventral margin setose. Mandible, incisor smooth, one small seta proximal an incisor, with two accessory setae, lacinia mobilis absent in right and left mandible; molar triturative, setose; palp 3- articulate, article 2, twice the size of the article 1, with setae in apical margin, article 3, rounded in apical margin, with two setae. Maxilla 1, inner plate with thin setae in lateral margins, without apical setae; outer plate, setal-teeth in 6/5 arrangement: ST1 1-cuspidate, ST2 and ST3 2-cuspidate, ST4 3-cuspidate, ST5 6-cuspidate, ST6 12- cuspidate and ST7 9-cuspidate (left maxilla 1, ST6 and ST7 10-cuspidate); STA conical, elongated, STB–D 1- cuspidate, small; palp 2-articulate, apical margin serrated, small subterminal seta. Maxilla 2, inner margin rounded apically, serrated setae in apical margin; outer plate, narrow, 2.6 × longer than wide, apical margin with slender setae. Maxilliped, inner plate narrow, thin setae in surface and apical margins, outer plate, inner margin straight, outer margin rounded, slightly serrated apically; palp 4-articulate, article 1 1.6 × longer than wide, article 2, elongated, 2.3 × longer than article 1, longer setae in outer margin, article 3 rounded apically, apical and outer margin with setae, dactylus with seta. Gnathopod 1, simple, coxa large, 1.5 × wider than coxa 2, expanded anteriorly; basis large, 1.5 × longer than wide, anterior margin and posteroventral corner with simple setae; ischium small, posterior margin with setae; merus, subtriangular, posteroventral corner acute, posterior margin with small setae distally and simple setae apically; carpus subrectangular, anterior margin with three setae, anteroventral and posteroventral corners with tuft of setae, ventral margin slightly concave; propodus with setae in anterodistal and posterodistal margin; dactylus with a wide nail, almost one and a half times greater. Gnathopod 2, minutely subchelate, coxa long, 2.6 × longer than wide, basis long, 5.3 × longer than wide, anterior margin with three simple setae; ischium long, 2.6 × longer than wide, anterior and posterior margins with one simple seta, posteroventral corner with tuft of setae; merus rounded, with convex protuberance anteriorly, posterior margin with thin setae, carpus slender, rounded ventrally, ventral margin and posterior margin setose; propodus long, 4 × longer than wide and 0.9 × carpus length, anterior and posterior margin setose, posterodistal corner with scales; palm acute; dactylus small, not reach the palmar angle, with nail. Pereopod 3, coxa long, 2.7 × longer than wide, basis 2.5 × longer than wide, anterior margin with two setae, posterior margin with one seta and posteroventral corner with a tuft of setae; ischium, posterior margin setose; merus, 1.5 × the carpus length, anteroventral angle expanded, with tuft of setae, posterior margin with simple setae; carpus small, rounded ventrally, propodus 1.3 × the carpus length; dactylus long, 0.6 × the propodus length, with nail. Pereopod 4, coxa expanded posteriorly, basis with two setae in anteroventral corner, ischium setose posteriorly, merus, anteroventral corner expanded, with tuft of setae, posterior margin setose; carpus setose posteriorly; propodus with two simple setae in anterior margin apically and seven in posterior margin. Pereopod 5, coxa rounded, 1.4 × wider than long, basis rounded, approximately as longer as wide, anterior margin setose; ischium small, about half merus length, one seta in anteroventral margin; merus, anterior margin setose, posterior margin with two tufts of two setae. Pereopod 6, coxa, anterior margin concave, posterior margin convex, with two setae; basis, anterior margin convex, with simple setae, posterior margin convex proximally and concave distally; ischium small, 0.3 × merus length, anterior margin with setae; merus, anterior margin with simple setae, posterior margin with one seta, posteroventral corner with a robust seta. Pereopod 7, coxa, anterior margin straight, posterior margin slightly convex; basis, anterior margin convex proximally, posterior margin slightly serrated; ischium small, posteroventral angle expanded ventrally; merus, anterior margin with stes of two setae, anteroventral corner with four setae, posterior margin with sets of two setae, one of than with accessory seta, posteroventral corner with three setae. Pleonites 1–3: Epimeral plate 3, posterior margin concave until half, posterodistal margin rounded. Uropod 1 long, peduncle subequal in length to rami, dorsal inner and outer margin with setae; rami subequal in length, inner and outer rami with setae in dorsal margin. Uropod 2, 0.7 × uropod 1 length, peduncle with setae in dorsal inner margin; rami subequal in length, inner ramus with constriction with a slender seta; outer ramus with setae in dorsal margin, with nail. Uropod 3, peduncle long, 2.75 × longer than wide and 1.3 × longer than outer ramus, dorsolateral flange strongly developed, dorsal margin with 5 setae, posteroventral corner with one seta; inner ramus, 0.8 × shorter than outer ramus, dorsal margin with two setae, outer ramus with thin setae in dorsal margin, rami with nail. Telson, about half longer than wide, apical margin very emarginated, with one seta in subterminal margins. Remarks. Shoemakerella ungulata sp. nov. differs from all other species of Shoemakerella in having an outer plate of maxilliped with a straight inner margin and a rounded outer margin; a strong nail in dactylus of gnathopod 1, the long propodus of gnathopod 2 and a strongly emarginated telson. In addition, it has a dorsally rounded upper lip, with anterodorsal margin straight, anterior margin concave, distal margin with notch, forming a rounded shape and ventral margin concave, different to S. cubensis and S. subchelata.

Aruga paracuru sp. nov. (Figs 9���13) Material examined. Holotype, female, ovigerous, 8.9 mm, Paracur�� Beach, Cear��, (03��25'S, 39��02'W), 20 August 2012, UFBA 3224. Paratype, female, Paracur�� Beach, Cear��, (03��25'S 39��02'W), 18 October 2012 in beach rock. UERJ 74. Type-locality. Paracur�� Beach, Cear��, Brazil. Etymology. The specific epithet corresponds to the beach Paracur��. This name comes from the Tupi indigenous language. Diagnosis. Upper lip, apical margin subacute, distal margin with a conical projection. Epimeral plate 3, posteroventral corner straight. Telson, lateral rounded. Description. ( Based on holotype). Head without setae. Lateral cephalic lobe subtriangular. Antenna 1, approximately same length as the antenna 2; article 1 of peduncle robust, subquadrate, three plumose setae in dorsal margin and two thin setae proximally, ventral margin with five plumose setae and distal corner with three slender setae; article 2, 0.3 �� article 1 length, apical corner with slender setae and distal corner with slender and plumose setae, article 3 half the length of article 2, with three slender setae in anterior margin; primary flagellum 12-articulate, two strong fields of callynophore, almost articles of flagellum with setae in anterior margin; accessory flagellum with 7 articles. Antenna 2, peduncle 13-articulate, anterior margin of articles with simple setae. Mouthparts forming a subquadrate bundle. Epistome and upper lip slightly separated, with one seta proximal, upper lip dominant, apical margin subacute, dorsal and ventral margins with small simple setae, apical margin with simple seta, anteroventral angle with a conical projection. Mandible, ventral margin with three robust serrate setae, incisor smooth, convex and laminar; lacinia mobilis in left mandible, modified a slender seta, with thin accessory seta; molar triangular, triturative, with small setae and scales; palp 3-articulate, article 1, about half length of article 2, article 2 with three simple setae in anterior margin, four pectinates setae in apical margin, article 3, 0.7 �� article 2 length, anterior margin concave, surface setose, apex with long setae. Maxilla 1, inner plate, tapering distally, tuft of thin setae in inner margin, two setae plumose in apical margin; outer plate, with 11 setal-teeth in 5/6 arrangement: ST1 asymmetrical, left ST1 2-cuspidate, right ST1 1-cuspidate, ST2���4 2-cuspidate, ST5 3-cuspidate, ST6 5-cuspidate, ST7 asymmetrical, left ST7 3-cuspidate, right ST7 5-cuspidate; STA���D 2-cuspidate; maxillar palp with 2 articles, article 2, about 7 �� longer than article 1, distal margin with slender setae and with subterminal seta. Maxilla 2, inner plate with small setae in medial margin, five plumose setae in subterminal margin, slender setae in apical margin; outer plate, some setae in subapical surface, slender setae in apical corner. Maxilliped, inner plate, subtriangular, with plumose setae in lateral margin, apical margin with three nodular setae and two simple setae; outer plate subrectangular; palp, 4-articulate, article 1, 0.5 �� article 2 length, slender plumose setae in lateral margin, article 2, lateral and apical margins with simple and slender setae, article 3, subrectangular, lateral and apical margins with simple setae, dactylus with subterminal seta. Pereonites 1���7: without setae. Gnathopod 1 simple, coxa well-developed, anterior margin convex, anteroventral corner produced, rounded, with simple setae, posteroventral corner rounded; basis, anterior margin with simple setae, posterior margin convex, posteroventral margin with tuft of setae; ischium, 0.4 �� length of basis, anterior margin concave, anteroventral corner rounded, with four setae, posterior margin setose; merus, expanded posteriorly, posterior margin with small setae proximally and slender seta posterodistally; carpus, subrectangular, posteroventral corner with four setae; propodus, 2.4 �� longer than dactylus, anterodistal and posterior margins with setae; dactylus, with small setae in posterior margin, with nail. Gnathopod 2, minutely subchelate, coxa, 2.2 �� longer than wide, setae in ventral margin; basis, 3.5 �� longer than wide, anterior margin with simple setae; ischium elongate, 4 �� longer than wide, with slender seta in surface distally; merus small, 2.5 �� longer than wide, anterior margin convex distally, posterior margin convex and covered by tufts of small setae, posterior corner with slender setae; carpus, 2.5 �� longer than merus, anterior margin slightly convex, with small setae and anteroventral corner with slender setae, posterior margin strongly convex, covered by scales, posteroventral corner with simple and slender setae; propodus, small, rounded, covered by setae, anterior margin convex, with setae, anterior margin with irregular and long setae, posterior margin with simple setae, posteroventral corner strongly convex, with scales, palm slightly serrate; dactylus very small, posterior margin serrate, the tip touches the palm, but not exceeding it. Pereopod 3, coxa 2.2 �� longer than wide, subequal in size to coxa 2, basis 3 �� longer than wide, anterior and posterior margins with setae; ischium small, anterior margin convex, posterior margin convex, with slender setae; merus elongate, 1.9 �� longer than wide, expanded anteroventrally, with slender setae, posterior margin setose; carpus, one setae on anteroventral corner, posterior margin setose; propodus with setae in anterior margin and on anteroventral corner, posterior margin setose; dactylus, 0.7 �� propodus length, with nail. Pereopod 4, coxa deeper than wide, with large posteroventral lobe, anteroventral corner quadrate; basis, 3.2 �� as longer than wide, posteroventral setose; ischium, merus, carpus and propodus setose posteriorly, merus elongate, 1.9 �� as longer than wide; carpus, 0.4 �� merus length, posteroventral margin with setae; dactylus with nail. Pereopod 5, coxa large, anterior margin slightly straight, anteroventral corner convex, posterior margin rounded; basis, anterior margin convex, with small setae and tufts of simple setae, posterior margin convex, serrate, posteroventral corner rounded; ischium, anteroventral corner with setae; merus, carpus and propodus, anterior margin with sets of setae; merus, posterior margin expanded, with sets of setae (1���1���1���2); dactylus with nail. Pereopod 6, coxa concave anteriorly, posterior margin convex, ventral margin rounded; basis, convex anteroventrally, with simple setae, posterior margin slightly serrate; ischium with setae in anterior margin, merus with sets of two setae in anterior margin and three setae in posterior margin, carpus, anterior margin with sets of setae with accessory setae (2���2���1���4), posterior margin, one seta, posteroventral corner with two setae with accessory setae; propodus, anterior margin with sets of two setae with accessory seta, posteroventral corner with four setae; dactylus with one setae in surface, with nail. Pereopod 7, coxa, posteroventral margin convex, basis anterior and posterior margin convex, setae in anterior margin, posterior margin serrate, ischium, setae with accessory setae in anteroventral corner, merus, anterior margin with three sets of setae with accessory seta, posterior margin with one seta, posteroventral corner with one seta with accessory seta. Epimeral plates 1���3: with setae in dorsal margin. Epimeral plate 3, posteroventral margin with straight angle. Urosomite 1���3, with dorsal carinas (two in lateral margins and one in medial margin). Uropod 1, peduncle 0.8 �� rami length, dorsal margin with two setae with accessory seta, posterior margin with one seta with accessory seta; inner ramus with two setae with accessory setae in dorsal margin; outer ramus, 1.3 �� longer than inner ramus, with three setae mediodorsally. Uropod 2, peduncle, two setae in dorsal margin; inner ramus with two setae dorsally and with constriction; outer ramus, dorsal margin with two setae, ventral margin with one seta. Uropod 3, setae with accessory setae in dorsal margin and two setae in posterior margin; inner and outer rami without setae. Telson entire, as long as wide, with scales in lateral surfaces, lateral margins rounded, strongly emarginated, with three setae in subterminal margins. Remarks: Aruga paracuru sp. nov. differs from A. holmesi by having: upper lip with apical margin rounded, forming a slightly anterior acute angle; epistome with conical projection; second article of mandibular palp with pectinate setae, third article setose; maxilla 1, setal-teeth, ST1 asymmetrical, left ST1 2-cuspidate, right ST1 1- cuspidate, ST2-4 2-cuspidate, ST5 3-cuspidate, ST6 5-cuspidate, ST7 asymmetrical, left ST7 3-cuspidate, right ST7 5-cuspidate, ST1 STA���D 2-cuspidate; outer plate of maxilliped subrectangular, palp, article 2 geniculate; urosomite 1���3 with dorsal carina, posteroventral margin with acute angle; and telson rounded strongly emarginated. Differently from Aruga oculata, A. paracuru has upper lip apically acute; epimeral plate 3, posteroventral margin almost forming an angle of 90��, distal margin acute; urosomites 1���3 with a dorsal carina, and telson subequal in length and width, with scales in lateral surfaces, lateral margins rounded, strongly emarginated, with three setae in subterminal margins., Published as part of Sorrentino, Rayane, Moraes, Elienai E. B. & Senna, Andr�� R., 2019, Four new species of Lysianassidae Dana, 1849 (Crustacea: Amphipoda) From Northeastern Brazilian coast, pp. 1-26 in Zootaxa 4585 (1) on pages 13-19, DOI: 10.11646/zootaxa.4585.1.1, http://zenodo.org/record/2636107

Aruga emarginata sp. nov. (Figs 1���4) Material examined. Holotype, male, 8.4 mm, Pirangi Beach, Parnamirin, Rio Grande do Norte, Brazil (5��54'22''S 35��15'27''W). Reef of Parrachos do Pirangi, September and October /2009 UFBA 3222. Type-locality. Pirangi Beach, municipality of Parnamirim, Rio Grande do Norte, Brazil. Etymology. The epithet refers to the apical margin of telson, strongly emarginated. Diagnosis. Upper lip forming a tuned structure in distal margin. Margin posterior of epimeral plate 3 rounded; telson, lateral margins tapering and strongly emarginated. Description. ( Based on holotype) Head and body without setae. Head, deeper than long. Lateral cephalic lobe large; eyes reniform. Antenna 1, peduncle, article 1, 1.2 �� as long than wide, dorsal margin slightly convex, ventral margin straight, with simple and plumose setae; article 2, 0.2 �� peduncle article 1 length, dorsal margin with one slender seta, ventrodistal corner with plumose and simple setae; peduncle article 3, dorsal margin with three setae; primary flagellum 11-articulate, first article with two strong fields of callynophore; accessory flagellum 7- articulate, articles with slender setae on anterior margin. Antenna 2 elongate, almost reaches the length of body; peduncle, article 3, 0.4 �� article 4 length; geniculate between peduncular articles 4 and 5, article 4, dorsal and ventral margins with small simple and plumose setae, ventral margin strongly convex; article 5 subrectangular, elongate, dorsal margin with sets of thin setae; flagellum 67-articulate, thirty-five proximal articles with setae in anterior margin, with robust calceoli. Mouthpart bundle: subquadrate. Epistome and upper lip slightly separate, upper lip produced, slightly concave dorsally, apically acute, forming a tuned structure in distal margin, ventral margin densely setose. Mandible, incisor smooth and laminar; right mandible without lacinia mobilis, left mandible with lacinia mobilis modified in a slender seta, three robust accessory setae in both; molar rounded, triturative; palp 3-articulate, article 2, subrectangular, 2.2 �� longer than article 1, anterior margin with slender setae; article 3, 0.6 �� length of article 2, surface setose, anterior and apical margins with simple setae. Maxilla 1, outer plate, simple setae in lateral margin, setal-teeth in 6/5 arrangement: ST1���4 subconical, 2-cuspidate, ST5 3-cuspidate, ST6 5-cuspidate, ST7 3-cuspidate; STA, thin, 2-cuspidate, STB and C 2-cuspidate, STD simple; palp 2-articulate, article 2, 4.1 �� longer than article 2, subrectangular, apical margin serrated, without subterminal seta. Maxilla 2, inner and outer plates narrow; inner plate, 3.5 �� longer than wide, lateral margin with simple setae, one serrate seta in subapical margin, apical margin with slender setae; outer plate slightly longer than inner plate, apical margin rounded, with slender setae. Maxilliped, inner plate narrow, lateral margin with plumose and pectinate setae, apical margin with two simple setae, without nodular setae; outer plate, inner margin with one seta, serrate apically, outer margin convex; palp, 5- articulate, article 1 subquadrate, two setae in outer corner, article 2, rounded apically, article 3 longer, twice longer than wide, lateral margin with slender setae, article 4, lateral margins with slender setae, apical margin with setae, dactylus, slender and slightly curved, with subterminal small setae. Gnathopod 1, simple, coxa large, anterior margin concave, anterodistal margin strongly produced and broadly round; basis, 1.8 �� longer than wide, anterior margin with slender setae, posteroventral corner with one seta; ischium anterior margin concave proximally, convex in anteroventral corner, with one seta, posterior margin slightly convex, with setae; merus subtriangular, posterior margin setose; carpus trapezoidal, setae on anterodistal and posterodistal corners; propodus, approximately 1.6 �� longer than carpus, slender setae in anterior and subterminal margins, posterior margin with setae; dactylus setose, slender and curved, with nail. Specimen is without gnathopod 2. Pereopod 3, coxa, 1.9 �� longer than wide; basis 2.7 �� longer than wide, posterior and posteroventral margins with setae; ischium, posterior margin with slender setae; merus and carpus with plumose setae in posterior margin, merus, elongate, 2.1 �� longer than wide, anterodistal margin expanded, carpus, 0.4 �� merus length; propodus, subrectangular, 1.2 �� longer than merus, six simple setae in posterior margin; dactylus elongate, 0.5 �� propodus length, with nail. Pereopod 4, coxa deeper than wide, posterior margin expanded distally, forming a quadrate angle; basis, subrectangular, posterior margin with setae; ischium subquadrate, anterior margin a slightly convex projection, posterior margin with setae; merus and carpus, posterior margin with plumose setae; merus, 2 �� longer than wide, expanded anteroventrally, with setae; carpus 0.5 �� merus length, propodus, subrectangular, anteroventral and posterior margins with setae; dactylus elongate, 0.7 �� length of propodus, with nail. Pereopod 5, coxa large, bilobate ventrally; basis strongly expanded posteriorly, anterior margin convex and setose, posteroventral lobe rounded; ischium small, about half length of merus, anteroventral corner with setae; merus, anterior and posterior margins with simple setae, rounded posteriorly; carpus and propodus subrectangular, anterior margin with setae, dactylus, with nail. Pereopod 6, coxa small, about half coxa 5 length; basis, anterior margin with setae distally, posterior margin slightly serrate, posteroventral lobe produced; ischium small, 0.8 �� merus length, anterior margin with setae; merus, anterior and posterior margins with setae, slightly produced posteroventrally; carpus and propodus elongate, anterior and posteroventral margins with setae; dactylus with seta proximally, with nail. Pereopod 7, coxa reduced, anteroventral margin slightly straight and forming a convex angle in posteroventral margin; basis, anterior margin convex proximally, posterior margin convex; ischium, anteroventral margin with setae, ventral margin with a slightly convex projection; merus subrectangular, setae in anterior and posterior margin. Epimeral plate 3, posteroventral corner rounded, posterior margin sinuous at its entire length and posteroventral corner rounded. Urosome 1���3 with three dorsal carinas, one in each lateral margin and one in medial margin. Urosomite 1, dorsal margin concave proximally, with row of setae in lateral carinas. Urosomite 2, short, 0.2 �� urosomite 1 length. Urosomite 3 subquadrate, as long as deep with one seta in lateral carinas. Uropod 1, peduncle subequal in length to rami, 2.8 �� longer than wide, dorsal margin with five setae and fine setae distally; rami subequal in length; inner ramus, dorsal margin with fine setae proximally and distally and two simple setae, with nail; outer ramus, with three setae ventrally, with nail. Uropod 2, peduncle, dorsal margin with three setae, medial margin with one seta; inner ramus, dorsal margin with fine setae and one simple seta, with a strongly constriction with a stout seta with accessory seta, with nail; outer ramus slightly longer than inner ramus, dorsal margin with three setae, with nail. Uropod 3, peduncle, dorsal margin with two setae, posterior margin with one seta, ventral margin with fine setae; inner ramus dorsal margin with plumose setae distally; outer ramus, 1.4 �� longer than inner ramus, dorsal margin with long plumose setae distally, ventral margin with fine setae. Telson, entire, apically emarginated, with simple setae and plumose setae at apicolateral ends. Remarks. Aruga emarginata sp. nov. differs from A. holmesi by the following characters (A. holmesi in parenthesis): epistome and upper lip separated by a thin and straight slit, upper lip, apical margin acute (welldefined separation, epistome has the anterior and ventral margins concave, upper lip rounded apically, ventral margin straight). Maxilla 1, outer plate, setal-teeth, ST1���4 subconical, 2-cuspidate (large, stout, ST1���3 weakly cuspidate to multicuspidate; ST4, 10-cuspidate), ST5 and ST7 3-cuspidate, ST6 4-cuspidate (ST5 and ST6 10- cuspidate, ST7 11-cuspidate), STD simple, without cusp (large, broad, 6-cuspidate). Maxilliped, inner plate subrectangular (subtriangular), without nodular setae (with 3 nodular setae); outer plate lateral margins straight, apical margin rounded medially (subovate). Urosome 1���3 with three dorsal carinas (without carinas). Telson strongly emarginated (slightly emarginated). Even though this is a male specimen, this species has the uropod 3, peduncle dorsal margin without plumose setae (A. holmesi that has superior margin with plumose setae). Furthermore, in A. holmesi the basis of pereopod 4 is larger in size and the anterior margin and anteroventral corner is convex and the basis of pereopod 5 is subquadrate. The new species has pereopod 4, anterior margin almost straight, and pereopod 5, anteroventral and posteroventral corner strongly rounded. Pereopods 6 and 7 of A. holmesi have the posterior margins of basis more serrated than A. emarginata sp. nov., and the posterodistal margin of pereopod 7 in this species is slightly more convex than A. holmesi. The species of North Pacific Ocean, Aruga oculata, is defined by having epimeral plate 3 with concave proximal half of posterior margin above a straight distal half, and the posteroventral corner unproduced and rounded, while the new species has the posterior margin sinuous along its entire length, and the posteroventral corner rounded. This posterior margin of epimeral plate 3 is also different from Aruga kieppe sp. nov.. Besides that, A. emarginata sp. nov. fundamentally differs from A. kieppe sp. nov. by the presence of urosome 1 with dorsal laterals setose carinas, without keel and telson emarginate, with apical margin concave. Aruga emarginata sp. nov differs from A. paracuru sp. nov. by having the upper lip slightly concave dorsally, apically acute, forming a tuned structure in distal margin, ventral margin densely setose. Mandible, molar rounded, triturative. Maxilla 1, setal-teeth STD simple; ST1 subconical, 2-cuspidate, ST7 3-cuspidate and STD simple. Maxilla 2, inner plate without pectinate setae. Telson with laterals slightly convex. Regarding A. falklandica, this species differs from other species of Aruga by the presence of scattered setae on dorsal margin of pereon and pleon. Because of its simple description is not possible to make a considerable differentiation and comparison., Published as part of Sorrentino, Rayane, Moraes, Elienai E. B. & Senna, Andr�� R., 2019, Four new species of Lysianassidae Dana, 1849 (Crustacea: Amphipoda) From Northeastern Brazilian coast, pp. 1-26 in Zootaxa 4585 (1) on pages 2-8, DOI: 10.11646/zootaxa.4585.1.1, http://zenodo.org/record/2636107

Material collected from three different states of the northeastern region of Brazil (Ceará, Rio Grande do Norte and Bahia) is analyzed. Four new lysianassid species of the genera Aruga and Shoemakerella are described. This paper includes the first record of Aruga in Brazilian waters and an identification key to world species of Aruga and Shoemakerella.