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Sexual dimorphism has long been stressed as a remarkable characteristic of Eulimidae snails. This idea is so common for this family that, even without information on the soft parts, some species were already identified as male or female, as observed in Nanobalcis worsfoldi Warén, 1990. Here, we investigated whether larger and smaller individuals of N. worsfoldi are female and male, respectively, and what are the most useful characteristics to differentiate the sexes. We analyzed shell morphology and morphometry, along with coloration of the soft parts of large and small individuals, and crosschecked our findings through histological analysis. Our results confirmed that (i) larger and smaller individuals are females and males, respectively; (ii) shell morphology is not useful, while morphometry is important to address sexual dimorphism; (iii) since shell length and width showed the most remarkable differences, they are considered the best parameters to predict the sex. Furthermore, conchological characteristics associated with histological analysis suggest that this species could be the first non-sessile eulimid known as a sequential hermaphrodite (protandric) with environmental sex determination, but this remains to be confirmed. Considering that most studies on eulimids are based on shells, the morphometric parameters used here may support future ecological/biological analyses in the family, such as parasitological prevalence, or parasitic burden related to sex.

The trophic relationships between two species of symbiotic gall-forming molluscs from the genus Stilifer (family Eulimidae) and two of their hosts-asteroid species, Linckia laevigata and Culcita noveaguineae, were investigated using the stable isotope analysis of carbon and nitrogen. The aim of present study was to identify the most preferable host tissue in the symbionts’ diet. We analyzed δ15N and δ13C values in tube-feet, gonads and digestive glands of the hosts-starfishes and in muscles of the molluscs. Both symbiont species did not differ to each other both in δ15N and δ13C values. The average δ15N and δ13C values of Stilifer variabilis were significantly different from the digestive glands and gonads of their host Culcita novaeguineae and did not show differences from the tube-feet of starfishes. A similar pattern was found in the symbiotic association of Stilifer utinomi and Linckia laevigata. The tube-feet of analyzed starfishes had significantly higher average δ15N and δ13C values than the digestive glands and gonads. Obtained isotopic signatures indicate that symbionts do not feed on the host's tissues, but take nutrients from their digestive system. It seems that the proboscis of Stilifer spp. absorbs the nutrients from the digestive system of the host-starfish thereby not disturbing significantly the host's immune system.

A new parasitic species of eulimid gastropod, Haliella seisuimaruaesp. nov., is described from bathyal (728–978 m) waters off the Pacific coasts of Japan. It shows the closest resemblance to the type species H. stenostoma from the North Atlantic and Barents Sea in having a tall shell with an almost straight outer lip, but differs in having a junction of the parietal wall and columellar lip at 38% of the aperture height from the suture (33% in H. stenostoma), a slightly wider aperture and a more curved and extended columellar lip. The holotype of H. seisuimaruaesp. nov. was found attached to an irregular sea urchin, Brissopsis sp. cf. luzonica (Spatangoida: Brissidae). This represents the first direct observation of parasitic ecology and echinoderm host for the genus Haliella. A new replacement name, Eulima tsushimensisnom. nov., is proposed here for Eulima stenostoma A. Adams, 1861, which is preoccupied by Eulima stenostoma Jeffreys, 1858 (type of Haliella).

Background Marine invertebrates are abundant and diverse on the continental shelf in Antarctica, but little is known about their parasitic counterparts. Endoparasites are especially understudied because they often possess highly modified body plans that pose problems for their identification. Asterophila, a genus of endoparasitic gastropod in the family Eulimidae, forms cysts in the arms and central discs of asteroid sea stars. There are currently four known species in this genus, one of which has been described from the Antarctic Peninsula (A. perknasteri). This study employs molecular and morphological data to investigate the diversity of Asterophila in Antarctica and explore cophylogenetic patterns between host and parasite. Results A maximum-likelihood phylogeny of Asterophila and subsequent species-delimitation analysis uncovered nine well-supported putative species, eight of which are new to science. Most Asterophila species were found on a single host species, but four species were found on multiple hosts from one or two closely related genera, showing phylogenetic conservatism of host use. Both distance-based and event-based cophylogenetic analyses uncovered a strong signal of coevolution in this system, but most associations were explained by non-cospeciation events. Discussion The prevalence of duplication and host-switching events in Asterophila and its asteroid hosts suggests that synchronous evolution may be rare even in obligate endoparasitic systems. The apparent restricted distribution of Asterophila from around the Scotia Arc may be an artefact of concentrated sampling in the area and a low obvious prevalence of infection. Given the richness of parasites on a global scale, their role in promoting host diversification, and the threat of their loss through coextinction, future work should continue to investigate parasite diversity and coevolution in vulnerable ecosystems.

This article lists and comments on the primary and secondary types represented in the collection of the Bailey-Matthews National Shell Museum (BMSM), on Sanibel, Florida, USA. The collection includes 464 type specimens, of which 15 are holotypes, representing 149 taxa, of which 145 are species and four subspecies. The BMSM collection is fully catalogued and posted online via the Museum’s website, in addition to iDigBio and GBIF. The publication of this annotated list intends to improve on the accessibility and promote this important group of name-bearing specimens, which includes, among other cases, types originating from orphaned collections and material poorly documented in the original descriptions. Eighty-two types were selected for illustration, and the photos of all BMSM types are available as part of the BMSM online collection catalog.

The present study reviews the taxonomy of the marine gastropods belonging to the family Eulimidae Philippi, 1853 from the continental slope off Northeast Brazil. The genera Abyssoaclis Barros, Mello, Barros, Lima, Santos, Cabral & Padovan, 2003 and Aclis Lovén, 1846 were not treated here. A total of 20 taxa were identified in this region, excluding Eulima hebes Watson, 1883, a species with a doubtful classification in Eulimidae. The species were assigned to the following genera: Costaclis Bartsch, 1947, Eulima Risso, 1826, Fusceulima Laseron, 1955, Melanella Bowdich, 1822, Ophieulima Warén & Sibuet, 1981, Sticteulima Laseron, 1955, Thaleia Warén, 1979, and Umbilibalcis Bouchet & Warén, 1986. The genera Sticteulima, Ophieulima and Umbilibalcis are reported for the first time in the southwestern Atlantic. Four species represent new records for the southwestern Atlantic. A redescription of the shell morphology is provided for: Costaclis egregia (Dall, 1889b), Melanella doederleini (Brusina, 1886), and Umbilibalcis lata (Dall, 1889b). Additional information to the original description are reported for other species. Melanella sarissa is considered as a synonym of Melanella cinca Dall, 1927. Six new species are described: Eulima cracentis sp. nov., Melanella paraabida sp. nov., M. adiastalta sp. nov., M. anapetes sp. nov., Sticteulima cabrali sp. nov. and S. canopusensis sp. nov. Lectotypes are designated for: Costaclis hyalina, C. egregia, Eulima ephamilla (Watson, 1883), E. psila and E. (?) hebes. Eulima sp. 1, Melanella sp. 1 and Melanella sp. 2 are potential new species, but the scarcity of material precludes a formal description at this moment.

As part of a study on holothurians from the southern Gulf of Mexico, some Holothuria mexicana Ludwig, 1875 were obtained for gut analysis. In two of them, a couple of eulimids were located inside the main tube of the respiratory tree. They were identified as Megadenus holothuricola Rosen, 1910, described from the Bahamas Islands, based on five specimens attached to the respiratory tree of H. mexicana . The original description was brief with few details, the type material is lost, and the species has not been found again. In this contribution, this species is confirmed for Campeche Bay, Mexico. The adult shell is globular to conical, transparent, thin, and fragile. Megadenus smithi sp. nov. from Palmyra Atoll, Central Pacific is described based on adult specimens. It differs from its congeneric species in its more robust shell, the pseudopallium does not cover the shell, and its short and contracted proboscis forms a thick disc. Further research on these eulimid parasites is now complicated in the southern Gulf of Mexico because of the holothurian population collapse due to over-exploitation of the fishery.

Goodingia is a crinoid-parasitic genus of the gastropod family Eulimidae, consisting of two named members: G. varicosa (Schepman, 1909) (type species) and G. capillastericola (Minichev, 1970). Due to their rarity, these species have been scarcely compared with each other. In this study, we assessed the taxonomic and phylogenetic relationships of Goodingia plus an undescribed eulimid species, whose parasitic ecology and shell profile accord with the genus, with morphological and molecular data. Shell resemblance justified a close relationship between the two species of Goodingia. Newly collected specimens of G. capillastericola from Papua New Guinea and Japan were morphologically indistinguishable but were genetically differentiated from each other (uncorrected p distances of 8.1–8.8% in mitochondrial COI sequences). Phylogenetic analysis recovered another crinoid-parasitic genus Annulobalcis as a paraphyletic group to G. capillastericola, suggesting the evolutionary transition of shell shape from slender to globose and of sexual strategy from separate sexes to simultaneous hermaphroditic. Unexpectedly, the Goodingia-like undescribed species was phylogenetically distant from Goodingia and even Annulobalcis. The present eulimid phylogeny also suggested the polyphyly of endoparasitic and radula-less taxa, respectively, and multiple acquisition of the pseudopallium in the endoparasitic taxa.

Parasitism and similar life styles such as carnivorous grazing or mucus feeding without killing the prey are important in marine gastropods. Some of the most diverse living gastropod families have this feeding behavior. Taxonomic uniformitarianism is the most important tool to infer parasitism or similar life styles in fossil gastropods. The extant family groups in question (Eulimidae, Epitoniidae, Pyramidellidae, Architectonicidae, Coralliophilinae, Ovulidae, Cerithiopsidae and Triphoridae) originate mostly in the Late Cretaceous (Cerithiopsidae in the Middle Jurassic) and Paleocene. They are performing an ongoing adaptive radiation and some of the mentioned families belong to the most diverse gastropod groups forming a considerable part of marine ecosystems regarding species richness and relative abundance. At the same time, origination and radiation of the carnivorous, commonly predatory Neogastropoda took place. This points to a trophic revolution in Gastropoda that forms an important aspect of the Mesozoic Marine Revolution. Most modern parasitic gastropods are small, high-spired, show high diversity and low disparity within families and belong to Apogastropoda. By analogy, some extinct gastropod families which show the same properties might have lived parasitic too (e.g., Pseudozygopleuridae, Zygopleuridae, Meekospiridae, Donaldinidae). However, this will remain speculative to a large degree until direct host associations are found. Direct evidence for parasitism is exceptional with the Palaeozoic platyceratid/crinoid interaction being one of the best studied examples. In Gastropoda, functional shell morphology may help to identify parasitism in the fossil record but this field is scarcely studied.

Gastropods from the family Eulimidae are known as parasites of all living classes of echinoderms. Here we determine the trophic relationships between ectoparasitic eulimids Echineulima mittrei and their hosts, sea urchins Diadema setosum in Vietnam. Stable isotope analysis showed the differences in δ13C and δ15N saturation in echinoderms tissues. The eulimids’ muscle and gonad tissues have the same carbon isotopic composition as the gonads of the hosts; however, they are more saturated with heavy nitrogen isotopes. The isotopic signatures indicate that ectoparasites feed on the fatty tissues of their hosts, especially gonads. Moreover, we suggest selective feeding in eulimids and possible migration of parasites’ proboscis among different host gonads and probably changes in the metabolism of parasites.

This study presents new records for 4 eulimid species (Gastropoda, Eulimidae) including Melanella eburnea (Megerle von Mühlfeld, 1824), Melanella hypsela (Verrill & Bush, 1900), Melanella sp., and Eulimostraca encalada Espinosa, Ortea & Magaña, 2006 found on the body wall of the sea cucumber Holothuria mexicana in Belize. Three of these records (M. hypsela, M. eburnea, and E. encalada) represent a first for the Western Caribbean ecoregion and close a distributional gap for these species in the Caribbean. The geographic distribution of M. eburnea is thereby expanded by ~800 km; M. hypsela by ~1,200 km and E. encalada by ~970 km in the Tropical Northwestern Atlantic province. This article presents for the first time H. mexicana as a new host record for E. encalada.

The present study reviews the taxonomy of four species of Melanella that occur in the littoral and infralittoral zones (up to 10 m depth) of Brazil: M. hypsela (Verrill & Bush, 1900), M. eburnea (von Muhlfeld, 1824), M. breviuscula (Dunker, 1875), and M. amblytera (Verrill & Bush, 1900). These species differ mainly in the dimensions and shape of the protoconch, body whorl shape, and outline of the outer lip. The geographic distribution of the species in the western Atlantic is updated, with new records for M. eburnea, M. breviuscula, and M. amblytera. All species are widely distributed in the Tropical Atlantic, but the published records of M. eburnea from West Africa and mid Atlantic remain dubious. Additionally, this study discusses the type status of Eulima species described by Verrill and Bush (Trans Conn Acad Arts Sci 10:513–544, pls 63–66, 1900), illustrating all of them. Here, we provide lectotype designations for M. hypsela, M. breviuscula, and M. amblytera.

New findings of four gastropod species: Melanella laurae, Hemiaclis ventrosa (family Eulimidae), Chrysallida sublustris and Odostomia acuta (family Pyramidellidae) are described. O. acuta was previously confused by Russian authors with H. ventrosa, distribution of both species in the Barents Sea is limited to the coastal waters of Finmark and Murman. M. laurae and C. sublustris were found for the first time in the adjacent to the Barents Sea parts of the Arctic Ocean.

Gastropods constituted one of the most successful faunal groups in the Danish Basin around the Cretaceous-Palaeogene (K-Pg) boundary, both with regard to abundance and diversity. Only 19 species were known previously; this number is here increased to 140. The end-Cretaceous Danish fauna is represented by 79 taxa of which 85 % became extinct at the boundary. A new fauna of 72 species arose within a remarkably short time interval of less than half a million years. The extinction seems to have hit rather randomly with regard to feeding strategies, while geographical range stands out as the single most important factor in survivorship. The succeeding speciation was controlled by changes in substrate and food availability, where non-carnivores and taxa dependent on a hard substrate were replaced by hunting carnivores and mud-adapted taxa in response to the disappearance of the Cretaceous bryozoan mounds. The gastropod genus Loxotoma Fischer, 1885 is renamed as Palaeoloxotoma nom. nov. due to its junior synonymy with a moth. 38 new species are erected. These are Acirsa torensis n. sp., Acmaea selandica n. sp., Ageria laxa n. sp., Ageria skeldervigensis n. sp., Amaea alicae n. sp., Amaea stevniensis n. sp., Amaurellina ravni n. sp., Arene jakobseni n. sp., Ataphrus (Ataphrus) knoesensis n. sp., Bathrotomaria jakobseni n. sp., Ceratia rodvigensis n. sp., Cerithiella selandica n. sp., Cerithiopsis restemlongis n. sp., Claviscala minor n. sp., Coniscala umbilica n. sp., Cranopsis cretacea n. sp., Cylichna stevniensis n. sp., Dolicholatirus lorenzi n. sp., Epalxis? rosenkrantzi n. sp., Epetrium s.l. skeldervigensis n. sp., Eucycloscala gracilicostatus n. sp., Fusinus schnetleri n. sp., Mathilda dania n. sp., Mesalia danica n. sp., Opaliopsis carlsbergi n. sp., Pseudocochlespira transversa n. sp., Pseudotoma danica n. sp., Tatara pseudosassia n. sp., Tectus? indecorus n. sp., Temnotropis stevniensis n. sp., Thereitis carlsbergi n. sp., Thereitis cretacea n. sp., Thylacodes contendis n. sp., Unitas heinbergi n. sp., Vatopsis heinbergi n. sp., Vexillum? rosenkrantzi n. sp., Vexillum tenestolidum n. sp. and Zebinella selandica n. sp.

A new genus and a new species of Eulimidae are described based on the shell morphology and on the host-parasite relationship of the type species. Eulimacrostomamicrosculpturata Souza & Pimenta gen. nov. and sp. nov. parasitizes a starfish of the genus Luidia and has an elongated, conical, straight, or slightly curved shell, a protoconch with a brownish spiral band and convex whorls, a peculiar large and broad aperture with a strongly protruding outer lip, and microsculpture of axial lines on the teleoconch. Four other species are included in the genus, all from the western Atlantic: Eulimacrostomachascanon (Watson, 1883), comb. nov., Eulimacrostomafusus (Dall, 1889), comb. nov., Eulimacrostomalutescens (Simone, 2002), comb. nov., and Eulimacrostomapatula (Dall & Simpson, 1901), comb. nov. Newly available material of Eulimacrostomapatula expands the known geographic distribution of this species in the Caribbean to the north coast of Brazil. Eulimacrostomachascanon and Eulimacrostomafusus and Eulimacrostomalutescens are known only by the type series which was re-examined. A redescription is provided for Eulimacrostomachascanon and Eulimacrostomafusus. Species within Eulimacrostoma differ mainly by teleoconch sculpture, the presence or absence of an umbilical fissure, and shell dimensions. Lectotypes are designated for Eulimacrostomachascanon, Eulimacrostomafusus, and Eulimacrostomapatula.

We have compiled a complete list of new marine molluscan taxa introduced by Tommaso Allery Di Maria, Marquis of Monterosato (1841–1927). The dates of publication of every single work have been checked against available evidence, and an updated bibliography is also presented. Finally, the type material of all marine taxa expected to be in the collection Monterosato (presently preserved in the Museo Civico di Zoologia in Rome) has been searched in the main collection, and all retrieved specimens have been catalogued. A large majority of the material has been found, representative specimens of each taxon have been illustrated, and remarks on nomenclature and taxonomy have been provided yielding 42 new synonymies, 46 nominal taxa rediscovered, and 6 new combinations.

During the observations of echinoderms in the natural conditions (South China Sea, Nha Trang Bay), a peculiar phenomenon of the rejection of symbiotic gastropods by host-starfish tissues was discovered. Later on, laboratory experiments were carried out in aquariums in order to find the cause of this phenomenon. Starfish Culcita novaeguineae bearing gastropods Stilifer variabilis were kept for 10 days in aquariums with no aeration and a gradual increase in water temperature. as a result, an unusual behavior of gallforming symbiotic gastropods was revealed: the apex of the shell began to stick more outof the surface of the host’s body, and in some cases sudden ejection of egg capsules by the symbionts was noted. In contract to the natural conditions, however, the symbionts neither died nor were totally rejected by the host’s tissues. There are plans to continue aquarium-based laboratory experiments with a larger selection of starfish and their symbionts, and to analyze various abiotic environmental factors (not only the temperature regime and the oxygen content in the water).

En 1826, Risso a décrit l’espèce Niso eburnea, un gastéropode du Zancléen (Pliocène inférieur) de la Trinité à Nice (Alpes-Maritimes), espèce type de son nouveau genre Niso. Compte tenu des informations souvent inexactes sur l’espèce type du genre NisoRisso, 1826 nous redonnons ici une description et des figures de cette espèce. Par ailleurs, le matériel type de Niso eburneaRisso, 1826, de la collection Risso, considéré comme perdu, a été récemment découvert dans la Collection de Paléontologie du Muséum national d’Histoire naturelle de Paris. Un lectotype est désigné ici pour fixer le statut de cette espèce.

The host preference of the symbiotic gastropods Annulobalcis albus, Annulobalcis vinarius and Annulobalcis maculatus in the family Eulimidae for their crinoid hosts was studied experimentally. Y-tubes of plexiglas allowed us to investigate the effect of chemical factors. Sea-water from aquaria containing different crinoids, or similar sea-water from aquaria without crinoids was fed into the distal parts of the Y-tube. From the results, we concluded that probably all the tested eulimids can recognize their hosts. Two are strictly host specific in nature, Annulobalcis albus and Annulobalcis maculatus, and they more often selected the water coming from the aquarium containing their hosts. They responded weakly to water from the aquarium without any crinoids. The third species, Annulobalcis vinarius, which in nature is not strictly host specific, preferred the crinoid Himerometra robustipinna (its main host) over Comatella nigra and Stephanometra tenuipinna (its alternative hosts) on which it is less often found in nature. These molluscs probably use Comatella nigra and Stephanometra tenuipinna as a reserve hosts and rarely colonize them. While chemoreception appears to be the major mechanism of host selection, the tested molluscs often demonstrated no reaction and this suggest that they do not need to settle on the crinoids immediately and that the symbiosis is facultative.

Fusceulima Laseron, 1955 and Halielloides Bouchet & Warén, 1986 are reported from the southwestern Atlantic for the first time. Halielloides ingolfiana Bouchet & Warén, 1986 is considered a valid name, and the taxon is distinct from its previous senior synonym Eulima verrilliana Bush, 1909 in shell shape and absence of an umbilicus. Fusceulima saturata sp. nov. is characterized by a conical shell, domed at the apex, a short ovoid aperture, and a distinct dark-brown spiral band near the suture. Fusceulima toffee sp. nov. also has a conical shell and a dome-shaped apex, but has a taller high aperture and the entire shell is dark brown. Halielloides cf. ingolfiana, Fusceulima cf. boscheineni, and Fusceulima cf. minuta, are here recorded from the continental shelf off southeastern Brazil. The nominal species of these taxa were originally described from the northeastern Atlantic. Their status remains dubious because of lack of information on their biology, anatomy and molecular data. Regarding shell morphology, we cannot distinguish the Brazilian specimens from species in the northeastern Atlantic with the material available. A series of short grooves close to the suture of the protoconch in all species of Fusceulima, including the type species Fusceulima jacksonensis Laseron, 1955, is a possible diagnostic character for this genus.

The gastropod family Eulimidae has attracted considerable attention as one of the most diverse groups of parasitic molluscs in terms of number of species and ranges of body plans and parasitic strategies. However, the phylogenetic position of the family has not been established within the Hypsogastropoda and this has hampered the inference of ancestral states in the evolution of the morphology and parasitic strategies. Here we present Bayesian and maximum likelihood phylograms of Hypsogastropoda based on nuclear and mitochondrial loci (18S and 28S rRNA, Histone H3, COI and 16S rRNA) and a better taxonomic sampling than in previous molecular analyses, to determine the position of Eulimidae. The resulting trees suggest Vanikoridae as the sister group of Eulimidae; the two families are collectively placed in the newly redefined superfamily Vanikoroidea, with Truncatelloidea and (potentially paraphyletic) Rissooidea as closest relatives. Vanikorids are protandrous hermaphrodites as are many eulimids and are essentially carnivorous, differing from the mostly gonochoristic and herbivorous/detritivorous Truncatelloidea and Rissooidea. The mode of feeding may have a phylogenetic signal also within Eulimidae, where radula-less species constitute a robust clade. Other new findings include a close affinity of the submarine-cave Pickworthiidae to Cerithioidea and a terminal position of Nystiellidae within the paraphyletic Epitoniidae.

The symbiotic assemblage associated with the tropical sea urchin, Salmacis bicolor was studied in the An Thoi archipelago, Vietnam. Five species of macrosymbionts were found on the surface of this echinoid host, including the polychaete, Ophiodromus sp. 3 (Hesionidae), gastropod, Vitreobalcis sp. (Eulimidae), shrimp, Allopontonia iaini (Palaemonidae), crab, Zebrida adamsii (Pilumnidae), and Ophiuroidea sp. This is the first record of A. iaini in association with S. bicolor in the coastal waters of Vietnam. The polychaete, Ophiodromus sp. 3 was located on the oral side of echinoids circled around the oral opening, while Vitreobalcis sp. was attached to the peristomial membrane. The shrimp, A. iaini and the crab, Z. adamsii were found among the spines; the latter was attached to the spines by chaelipeds. Of the 60 S. bicolor examined, 28 (46.6 %) were infested, with an average number of symbionts per host of 0.52. The prevalence increased with increasing sea urchin test size. We did not find symbionts on urchins whose test diameter was less than 35 mm. Almost all S. bicolor were inhabited by one symbiont, and in only three cases did we find two symbionts belonging to two different species on one host. Polychaete, Ophiodromus sp. 3 occurred most often, and only 1–6 specimens of the other species were found. The composition of the assemblage associated with S. bicolor was compared with that known for other assemblages associated with tropical sea urchins. The ecological characteristics of the association and the possible host-symbiont relationships are discussed.

Hypermastus tokunagai is a eulimid gastropod infecting the sand dollar Scaphechinus mirabilis. The eulimid is easily detached from the host and thus regarded as a temporary parasite. In this study, the growth and reproductive cycle of H. tokunagai were investigated using specimens collected from S. mirabilis in the western Seto Inland Sea, Japan. Newly recruited individuals of H. tokunagai appeared in early autumn and grew rapidly, while growth was retarded from mid-autumn to winter months. A second rapid growth occurred the following summer. Based on the growth pattern, the life span of H. tokunagai was estimated to be more than 20 months. This longer life span compared to other eulimids could be due to the accessibility and population stability of its host S. mirabilis. Maturation of H. tokunagai occurred within a short period in the summer, and was synchronized with the second growth phase. Hypermastus tokunagai showed size dimorphism between sexes and an investigation on change in shell shape with growth revealed that this characteristic can be attributed to the female's acquisition of a larger shell within a short time during its maturation period.

Parasitic gastropods of the genus Annulobalcis Habe, 1965 (family Eulimidae), associated with the crinoids (comatulids) are common in Nhatrang Bay (Southern Vietnam). Morphological examination of Annulobalcis specimens, collected in this area revealed four distinct forms, significantly different also in host specificity. Mitochondrial cox1 sequence data have shown these forms to comprise four distinct species, their relationships are discussed. As a result of morphological and molecular studies, four new species of the genus Annulobalcis are described: A. albus n. sp., A. wareni n. sp., A. maculatus n. sp., and A. vinarius n. sp. The three former species appeared to be strictly species specific in their choice of host (parasitizing a single host species each), while the latter was found on a number of hosts, although mostly on a single species. Speciation in relation to host specificity of Annulobalcis is discussed.

The new combined attachment and feeding trace fossil Oichnus halo isp. n. is described from oral surfaces of Campanian and Danian Echinocorys tests. It shows striking conformity with traces produced by Recent eulimid gastropods of the genus Thyca parasitising the asteroid Linckia laevigata . The trace is characterised by a central penetration surrounded by the eponymous circular groove. The occurrence of Oichnus halo isp. n. in the Campanian is contemporaneous with the first appearance of eulimid gastropods in the fossil record and indicates that the eulimid–echinoderm parasitic interaction was already established in the Late Cretaceous.

The abyssal depths of the polar oceans are thought to be low in diversity compared with the shallower polar shelves and temperate and tropical deep-sea basins. Our recent study on the gastropod fauna of the deep Southern Ocean gives evidence of the existence of a rich gastropod assemblage at abyssal depths. During the ANDEEP I and II expeditions to the southern Drake Passage, Northwestern Weddell Sea, and South Sandwich Trench, gastropods were collected by bottom and Agassiz trawls, epibenthic sledge, and multicorer, at 40 stations in depths between 127 and 5194 m. On the whole, 473 specimens, corresponding to 93 species of 36 families, were obtained. Of those, 414 specimens were caught below 750 m depth and refer to 84 (90%) benthic species of 32 (89%) families. Most families were represented by a single species only. The numerically dominant families were Skeneidae and Buccinidae (with 10 and 11 species, respectively), Eulimidae and Trochidae (with 9 species each), and Turridae (6 species). Thirty-Seven benthic deep-sea species (44%) were represented by a single specimen, and another 20 species (24%) were found at a single station, suggesting that more than two thirds of Antarctic deep-sea gastropod species are very rare or have a very scattered distribution. Of the 27 species occurring at two or more deep-sea stations, 14 were collected with different gear. Approximately half of the deep-water species are new to science or have been recently described. The present investigation increases the total number of recorded benthic Antarctic deep-sea gastropods (below 750 m) from 115 to 177. The previously known depth ranges have been extended, often considerably, for 31 species. The collected deep-sea gastropods comprise both eurybathic shelf species (29%) and apparently true deep-sea species (58%); some of the latter may belong to a so far unknown Antarctic abyssal fauna. Geographical ranges of the collected Antarctic benthic deep-sea gastropod species appear limited, and all these 84 species seem endemic to Antarctica south of the Polar Front. Comparing diversity and abundances based on epibenthic sledge samples, there is no clear relationship between Antarctic deep-sea gastropod abundance and species richness with depth. However, both Antarctic and adjacent deep-sea areas are still far from being adequately sampled to allow more comprehensive conclusions.

The shell-less, endoparasitic gastropod, Asterophila japonica , was collected from two species of sea star, Leptychaster anomalus Fisher, 1906 and Ctenodiscus crispatus (Retzius, 1805) in Toyama Bay, Japan. All observed individuals were located on the aboral side of the host's disk (except one specimen parasitizing the arm) between the epidermis and the coelomic epithelium. More than one large individual frequently co-occur on a single host. The body plan of A. japonica is surprisingly modified from that of general gastropods; organs unrelated to digestion and reproduction are greatly reduced, simplified or completely lost. Dimorphism of body size is striking between males and females: males are much smaller than females and are attached to the surface of the pseudopallium of females. Females deposit and brood an egg mass(es) in the pseudopallial cavity until the eggs develop to veliger larvae. At the late developmental stage, brooded larvae reduce the velum and develop the foot for crawling, suggesting lecithotrophic development with or without a short planktonic stage. It is uncertain as to how the larvae can find and parasitize the next generation of the host. The systematic placement of Asterophila in the family Eulimidae is supported by three characters, viz. parasitism on echinoderms, smooth hydrophobic protoconch, and the enclosure of the visceral mass with the pseudopallium.

Eighteen gastropod and seven bivalve species are reported from Eocene to Oligocene cold-seep carbonates in Washington State, USA. Four species are new (Niso littlei, Turrinosyrinx hickmanae, Xanthodaphne? campbellae, and Lurifax goederti), and 16 are described in open nomenclature. Previously unknown features of protoconch or prodissoconch morphology and/or shell microstructure are provided for Retiskenea statura (Goedert and Benham), Provanna antiqua Squires, Nuculana? aff. N. grasslei Allen, and Bathy- modiolus willapaensis (Squires and Goedert). Modiolus (M.) willapaensis is placed within Bathymodiolus based on the elliptical- triangular shape of its juvenile shell, indicating that the divergence between vent/seep and whale/wood-fall inhabiting bathymodiolines took place at least 40 Ma. The first fossil species of the vent/seep genera Pyropelta (Pyropeltidae), Lurifax (family uncertain), and Catillopecten? (Propeamussidae) are reported. Niso (Eulimidae), Xanthodaphne, Turrinosyrinx, Benthomangelia (Turridae), Ledella (Nuculanidae), Tindaria? (Tindariidae), and Delectopecten (Pectinidae) are reported for the first time from fossil cold-seep assemblages. Larval developmental strategies are inferred from protoconch and prodissoconch morphologies in 14 species, which largely reflect the species' phylogenetic groups, as in modern vent and seep molluscs. The data presented here indicate that the radiation of toxoglossate turrids (Gastropoda) into deep water took place already in the Oligocene, and not in the Miocene as previously thought. Healed shell injuries and presumed naticid drill holes represent the oldest known fossil evidence of predation at cold-seeps.

Pyramidelloides dolini n. sp., older strongly sculptured eulimid, is described from the Middle Eocene of southwestern Alabama (Gosport Sand). This new species probably had a planktotrophic larval stage similar to the recent Indo-West-Pacific species. Relationship with the species of the genus Palisadia is discussed. Geographic distributions of both the fossil and the recent species of the genera Pyramidelloides and Palisadia support finally a classic pattern in tropical marine biogeography: a discontinuous geographic range between Indo-Pacific and Caribbean provinces.

Some shells of Ophieulima minima are reported from the Tuscan archipelago. This is the first record of the genus Ophieulima from the Mediterranean Sea. Hypotheses about its host are considered.

A new species of Melanella is described from New Zealand. The last turn of the body emits a lime yellow glow, the first record of luminescence in Eulimidae and the first record of yellow luminescence in a gastropod (otherwise blue). It is parasitic on the holothurian Ocnus brevidentis (Hutton, 1872). Melanella archeyi (Finlay, 1928) and M. aucklandica (Suter, 1909) are recognised as distinct species, and outer lip profiles of the holotypes are illustrated.

The family Eulimidae comprises minute gastropods best known for its parasitic habit on Echinodermata. Despite this, reports of association between eulimids and echinoderms are rather scarce. In this study, two new hosts, Parathyone suspecta and Holothuria grisea, were observed for the eulimid Melanella eburnea. This is the first record for the latter species in Brazilian waters. In addition we observed the association between the eulimid M. hypsela and the holuthurian Isostichopus badionotus, which is a new record for Brazilian waters.

The malacofauna of Hawaii is rather well-known, owing to Kay (1979) and Severns (2011). Both works stand out because they include a large number of the generally under-represented micromollusks (

The current article provides the first record of Annulobalcis aurisflamma Simone and Martins, 1995 outside São Paulo state, Brazil. Herein we extend its geographical distribution to northeastern Brazil.

The intertidal sand dollar Arachnoides placenta is parasitized by the eulimid Hypermastus placentae at Pallarenda Beach, Townsville, Queensland. A. placenta is the only echinoderm species in the region with which H. placentae associates. Sand dollars are distributed in an aggregated pattern within the littoral zone at Pallarenda Beach, and the distribution of parasites within the adult sand dollar population conforms closely to Poisson expectations. A. placenta adults in all size classes are equally susceptible to parasitization by H. placentae, whereas juveniles are not parasitized; host selection may be determined by a requirement for host gonadal tissue in the diet of the parasite. Infestation rate and number of parasites per host decrease as host density increases. Parasite body size is not related to host body size.

The association between the sand dollar, Arachnoides placenta, and the eulimid gastropod, Hypermastus sp., was investigated at Pallarenda Beach, Townsville, Queensland. Hypermastus sp. is a temporary ectoparasite of A. placenta that penetrates the latter's test to ingest gonad tissue and coelomic fluid. The infestation rate normally varies between 8 and 15% but increases in winter to 26%. This seasonal increase in the infestation rate appears to be due to an increase in the duration of attachment of female parasites. Hypermastus sp. is sexually dimorphic, with males being, on average, 0.6 times the size of females. Individuals may be protandric sequential hermaphrodites.

Eulimindae (Prosobranchia) of the New Zealand region that parasitise echinoderms are recorded and discussed. Fuscapex ophioacanthicola n.gen. & sp. is parasitic on Ophioacantha sp., Ophieulima fuscoapicata n.sp. is a parasite of Ophioactis profundi Lutken & Mortensen, Punctifera ophiomoefrae n.gen. & sp. lives partly buried among the radial shields of Ophiomoeris projecta Matsumato, and Stilapex sp. is recorded, but not described, from Ophiothrix oliveri Benham (all hosts ophiuroids). Stilifer sp. lives in galls in an undescribed oreasterid (Asteroidea). Annulobalcis marshalli n.sp. is described from Crotalometra rustica (A. H. Clark) (Crinoidea). Eulima infrapatula Murdoch & Suter is transferred to Sabinella Monterosato and recorded from Ogmocidaris benhami Mortensen; Fusceulima goodingi n.sp. is described from Centrostephanus rodgersi (A. Agassiz) (both hosts echinoids). Two earlier records of sea urchin parasites from New Zealand are discussed, and the species are referred to Pelseneeria.

Eleven new genera and 17 species are described, with one exception parasites on echinoderms: Trochostilifer gen. n. with T. domus sp.n. (type species) (Philippines) on Stylocidaris efftuens, T. mortenseni sp.n. (New Caledonia) on Prionocidaris australis and T. slriatus (Hedley) on P. baculosa annulifera; Ophioarachnicola biformis gen. et sp.n. (Solomon Is.) on Ophio-arachna incrassata; Hemiliostraca sloani sp.n. (Aldabra I.) on Ophiomyxa australis; Robil-lardia solida sp.n. (Loyalty Is.), host unknown. Ersilia Monterosato is transferred from Lacunidae to Eulimidae, E. stancyki sp.n. (Florida) is a parasite of Ophiolepis elegans. Hyper-mastus echinodisci sp.n. and H. sauliae sp.n. (both Borneo) are parasitic on Echinodiscus bisperforatus; Monogamus parasaleniae sp.n. (Tonga I.) on Parasalenia gratiosa. Scalari-balcis gen.n. is erected for Mucronalia angulata Mandahl-Barth. Concavibalcis scalaris gen. et sp.n. is described from the Philippines, host unknown. Echiuroidicola cicatricosa gen. et sp.n. (Malaysia) is a parasite on the echiuroid Ochetostoma erythrogrammon. Peasistilifer gen.n. (type species Mucronalia nitidula Pease) is erected for a group of holothurian parasites. Prostilifer gen.n. is erected for Eulima subpellucida Pease, parasitic on Pacific holo-thurians. Paramegadenus scutellicola sp.n. (Pacific) is parasitic on Stellaster incei, P. incerta sp.n. on an Australian starfish. Asterolamia hians gen. et sp.n. is described from Astropecten indicus and A. cingulata from Craspidaster hesperus, both Pacific. Microstilifer gen.n. is erected for Stilifer auricula Hedley. Vitreobalcis gen.n. is erected for Apicalia holdsworthi H. Adams, a parasite of Mespilia globulus and V. laevis sp.n. (from Synaptula purpurea, Australia) is provisionally placed here. Luetzenia asthenosomae gen. et sp.n. (Australia) and L. toki Habe are both parasites on Asthenosoma.

The free living eulimid gastropodMelanella albaBowdich, 1822 is a temporary ectoparasite on echinoderms and, in Kilkerrin Bay on the west coast of Ireland, this species is found exclusively associated with the holothuroidNeopentadactyla mixta(Östergren), 1898.Melanellautilizes a highly specialized acrembolic proboscis to penetrate the integument and ingest the internal tissues of this holothuroid. That portion of the proboscis which penetrates integument bears a highly developed secretory epithelium composed of granular and goblet secretory cells. As the proboscis is unfolded into the host's integument by a combination of increased hydrostatic pressure and muscular movements, secretory material is released from this epithelium and appears to bring about a rapid loosening of the connective tissue elements of the host. The possible mechanism by which the integumental connective tissue is altered to allow unfolding of the proboscis into the coelomic cavity of the host is discussed.

All species that have been described in Apicalia, except the type-species, are transferred to other eulimid genera. Three species earlier included in other genera and four new species are placed in Apicalia, viz. A. angulata sp.n. A, cicatricosa sp.n. A. echinasteri sp.n. (all three Queensland), and A. habei sp.n. (Japan). Those of which the hosts are known are all ectoparasites of asteroids. Two of the seven species previously included in Stilapex are excluded and four species earlier placed in other genera are transferred to Stilapex. The members of the latter genus are parasites of ophiuroids. Tropiometricola gen.n. is erected to include Stilifer sphaeroconcha Habe, a crinoid parasite. Parvioris gen.n. is described with Eulima fulvescens A. Adams as type species. A list of species described in eulimid genera and fitting Parvioris is given. P. australiensis sp.n. (W. Australia), P. blakeae sp.n. (Mauritius), P. mortoni sp.n. (Hong Kong), and P. noumeae sp.n. (New Caledonia) are described. Those species of which the host is known, are all ectoparasites of starfishes.

All species that have been described of the genera mentioned in the title are listed and their systematic position given. The species of Stilifer (with 11 species, including S. inflatus sp.n. and 5. concavus sp.n.) are parasites of starfishes. Scalenostoma (3 species) are parasites of stone corals. Thyca (with 8 species) is removed from Capulidae, and included in Eulimidae. T. hawaiiensis sp.n. is described. The species of Thyca are parasites of starfishes. The species of Mucronalia (including M. trilineata sp.n.) are probably parasites of ophiuroids and Echineulima (with 4–6 species, including E. ponderi sp.n.) are parasites of echinoids. All species are figured, their characteristics are given and their host species and distributions are listed. Keys are given to the species of each genus, except Mucronalia. The genera Stilimella Laseron and Hyperlia Pilsbry are synonymized with Scalenostoma and the genera Kiramodulus Kuroda, Granulithyca Habe and Bessomia Berry are considered subgenera of Thyca.

A new gastropod of the Eulimidae, parasitic on an ophiuroid, is described from off the NE United States, living at a depth of about 4000 m. It is attached by its snout to the oral side of an arm, close to the mouth of the host and penetrates the body wall with an acrembolic proboscis which ends in the ring canal of the host. The parasite usually occurs in pairs, a male and a female. The morphology shows several adaptations to a parasitic life.

The anatomy and biology of Eulima bilineata Alder is described and compared with PyramidelIoides miranda (A. Adams) and P. angusta (Hedley). All the species are parasitic on ophiuroids, have a ptenoglossate radula, an acrembolic proboscis with a pair of salivary glands close to the buccal mass and a reduced stomach with two histologically different digestive glands. The males have a well developed penis, the female a partly open or closed pallial oviduct. The central nervous system is concentrated. The sub- and supraoesophageal ganglia are completely integrated in the nerve ring. In Eulima, the supraoesophageal ganglion is split into two parts. Few differences were found between the species investigated, and it is concluded that Pyramidelloides should be classified in Eilimidae, not in Rissoidae where it has been placed previously.

The young stages of the members of the family Eulimidæ are little known, the only reference to any species apparently being that of Loven (1844) who briefly notes and figures a veliger which he attributes to Eulima distorta (=Balcis devians). This has a very oblique shell and was probably a week or two old. A comparison of this figure with the apex of Balcis devians from Plymouth and its larvæ in the plankton makes one rather uncertain of its identity but shows that even in those early times it was known that a Eulima could remain some time in the plankton as a veliger.