identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
884251566533FFCEFCBFA7ED0C94FE59.text	884251566533FFCEFCBFA7ED0C94FE59.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Neolepetopsis McLean 1990	<div><p>GENUS NEOLEPETOPSIS MCLEAN, 1990</p> <p>Type species: Neolepetopsis gordensis McLean, 1990 (by original designation).</p> <p>Diagnosis: Small-sized (&lt;10 mm) neolepetopsid limpets with coarse, typically clathrate shell sculpture. Shell interior with transparent areas. Radula with sturdy central rachidian; five or seven cusped teeth, usually well mineralized for Neolepetopsidae (Warén &amp; Bouchet, 2001; McLean, 2008). Shell profile typically low, flat limpet-form, but may be constricted by the substrate type and range from flat to tall in some species (McLean, 1990).</p> </div>	http://treatment.plazi.org/id/884251566533FFCEFCBFA7ED0C94FE59	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Chen, Chong;Zhou, Yadong;Watanabe, Hiromi Kayama;Zhang, Ruiyan;Wang, Chunsheng	Chen, Chong, Zhou, Yadong, Watanabe, Hiromi Kayama, Zhang, Ruiyan, Wang, Chunsheng (2022): Neolepetopsid true limpets (Gastropoda: Patellogastropoda) from Indian Ocean hot vents shed light on relationships among genera. Zoological Journal of the Linnean Society 194: 276-296, DOI: 10.1093/zoolinnean/zlab081
884251566534FFCDFF31A0920855F97D.text	884251566534FFCDFF31A0920855F97D.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Neolepetopsis prismatica Chen & Zhou & Watanabe & Zhang & Wang 2022	<div><p>NEOLEPETOPSIS PRISMATICA SP. NOV.</p> <p>(FIGS 2A–D, 3, 4)</p> <p>Z o o B a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org:act: B0DF7474-BE16-461E-B07E-632D276D0E66</p> <p>Diagnosis: Medium-sized Neolepetopsis (SL ≤ 4.8 mm) with much stronger concentric sculpture compared with only diminutive, nearly absent radial sculptures and lacking nodes at the intersecting points. Spacing of concentric sculptures variable between ~50 and 150 µm within the same individual. Shell oval; posterior end narrower than anterior; always low profile and flat limpet-form, with apex on the midline and nearly central or very slightly anterior. Symmetrical protoconch 220 µm in length. Greenish periostracum present. Interior of the semi-transparent shell carrying strong prismatic structural colour. Radula with short shafts and heavy, well-mineralized cusps.</p> <p>Type locality: Inactive sulfide deposits, Daxi hydrothermal vent field, Carlsberg Ridge.</p> <p>Type material: Holotype (RSIO 38210; Fig. 2A) in 95% ethanol, SL 4.1 mm, SW 3.1 mm, Daxi vent field, Carlsberg Ridge, 60°10.8′E, 6°48.0′N, 3450 m deep (station ‘DV128’), R / V Xiangyanghong 9 cruise DY38, by a seven-function manipulator of HOV Jiaolong, dive 128, 11 March 2017. Paratype 1 (NSMT-Mo 79214; Figs 2B, 3), 95% ethanol, SL 4.2 mm, SW 2.9 mm, rehydrated once for photography of soft parts and then stored in 70% ethanol. Paratype 2 (RSIO 38211; Fig. 2C), 95% ethanol, SL 4.0 mm, SW 2.8 mm. Paratype 3 (NSMT-Mo 79215; Fig. 2D), 95% ethanol, SL 3.5 mm, SW 2.4 mm. Paratype 4 (NSMT-Mo 79216), 95% ethanol, SL 4.1 mm, SW 2.9 mm. Paratype 5 (NSMT-Mo 79217), 95% ethanol, SL 3.9 mm, SW 2.8 mm. Paratype 6 (RSIO 38212), 95% ethanol, SL 4.8 mm, SW 3.3 mm. Paratype 7 (NSMT-Mo 79218), 95% ethanol, five small specimens. Paratype 8 (RSIO 38213), 95% ethanol, five small specimens. Paratype 9 (RSIO 38214), 95% ethanol, shell only, SL 4.8 mm, SW 3.1 mm. All paratypes are from the same lot as the holotype.</p> <p>Description: Shell(Fig.2A–D)thin, mostlytransparent, carrying strong prismatic structural coloration on internal surface. Shell length ≤ 4.8 mm, shell width ≤ 3.3 mm (4.1 and 3.1 mm for holotype, respectively). Small area corresponding to apex thickest, slightly opaque, thinning out towards periphery. Elliptic to oval in shape, with posterior end slightly narrower than anterior end; shell length-to-width ratio between 1.3:1 and 1.5:1. Always low in profile, with nearly flat shell edge. Apex at midline, nearly central or slightly anterior. Sculpture predominantly concentric (Figs 2, 3C), with strong concentric ribs at somewhat variable interspaces between ~50 and 150 µm, even within each individual. Radial sculpture almost lacking, with only weak radial striations. No nodes formed at intersection between two directions of sculptures. Protoconch (Fig. 3A, B) symmetrical, typical of patellogastropods, 220 µm in length. Finely pitted sculpture present on protoconch, especially obvious at distal end. Thin, greenish layer of periostracum present over teleoconch. Muscle scars not clearly discernible.</p> <p>Radula (Fig. 3D, E) with seven mineralized teeth (rachidian, two pairs of laterals, pluricuspid) on each row and four non-mineralized marginal teeth, width ~25 µm. Cusps of mineralized teeth gradually descending in horizontal position from rachidian outwards. Rachidian sturdy; base laterally expanded with narrow, short shaft ending in a single tapering, overhanging cusp. Inner lateral also with overhanging, but narrower, cusp stemming from narrow shaft possessing strong indentation to accommodate expanding base of rachidian. Outer pair of laterals similar to inner pair but sturdier, with much thicker shaft and with heavier, triangular cusp. Pluricuspid tooth with broad cusp bearing three tapering tips, the two outer ones being much larger. Shaft of pluricuspid with broad basal–lateral indentation, extension of which connects with inner marginal tooth. Inner marginal with broad, overhanging edge, on strongly indented, broad shaft. Outer marginal separated from inner marginal, much reduced, with narrow, tapered, overhanging edge.</p> <p>The soft parts are shown in Figure 4. Cephalic tentacles simple, tapering; left and right tentacles of equal size. External evidence for eyes absent. Mouth with thick outer lip; labial lobe well developed. Jaw present. Foot oval, with unciliated rim. Large sole demarcated from rim by deep groove. Epipodium lacking. Shell muscle U-shaped, situated along posterior two-thirds of body, separated into several oval-shaped bundles decreasing in size from anterior towards posterior end. Mantle edge with numerous short, presumably sensory papillae; fully contracted in specimens examined. Mantle cavity approximately one-third of body length. Pericardium situated on left side of mantle roof, heart monotocardian, with anterior auricle and posterior ventricle (by transparency). Right side of mantle roof with anus just left of the urogenital opening situated on sizeable papillae. Ctenidium lacking. Sexes separate; gonad located above foot at mid-ventral position, visible from dorsal view by transparency posterior to pericardium. Two kidneys present; left kidney minute compared with sizeable right kidney at far posterior. Intestine and stomach embedded in large digestive gland comprising numerous branching tube-like structures. After two loops, intestine transitions to rectum, running posterior–anteriorly before curving to right, with anus exiting at right side of mantle roof. Rectum packed with dark oval faecal pellets. Operculum lacking.</p> <p>Etymology: From the Latin adjective prismaticum meaning ‘prismatic’, originally derived from Ancient Greek Πρίσµα, prísma, something sawn. It is named in reference to the brilliant iridescence of its shell, particularly the inner surface, owing to structural colour.</p> <p>Distribution: Currently known only from inactive sulfide chimneys of the Daxi hydrothermal vent field on the Carlsberg Ridge, Indian Ocean. The Daxi field has a central focused venting area surrounded by a region characterized by numerous extinct sulfide chimneys (Wang et al., 2021), on which the present new species was collected.</p> <p>Remarks: Five other described species are currently known in Neolepetopsis, all from the eastern Pacific Ocean. The shell sculpture of N. prismatica differs from these species in lacking clear nodes where the concentric ribs meet the radial ones, owing to radial sculpture being extremely weak. The protoconch of N. prismatica is much smaller than that of Neolepetopsis densata McLean, 1990 from East Pacific Rise vents (McLean, 1990), the only other Neolepetopsis species with a known protoconch (220 vs. 400 µm). The radula of N. prismatica is also most similar to N. densata, with shorter shafts and more prominent cusps than N. gordensis from vents on the East Pacific Rise (McLean, 1990) and also recorded at hydrocarbon seeps off Peru (although whether this record truly represents N. gordensis remains uncertain; Warén &amp; Bouchet, 2001). The radula of other Neolepetopsis species (where known) has either two (N. gordensis) or four (N. densata) cusps on the pluricuspid (McLean, 1990), whereas that of N. prismatica has three. The short shafts of the N. prismatica radula are similar to N. densata but unlike the longer shafts of N. gordensis. The radula of Neolepetopsis nicolasensis McLean, 2008 from a whale fall off California is unique in having only five cusped teeth instead of seven (McLean, 2008) and therefore cannot be confused with the present new species. The flat shell with green periostracum and stronger concentric sculpture is also seen in Neolepetopsis verruca McLean, 1990 and Neolepetopsis occulta McLean, 1990 from vents on the East Pacific Rise (McLean, 1990), but the radial striation on N. prismatica is far weaker than in either of these two species, both also exhibiting nodes where the two sculpture types meet. For differences from Neolepetopsis ardua, see below under that species.</p> </div>	http://treatment.plazi.org/id/884251566534FFCDFF31A0920855F97D	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Chen, Chong;Zhou, Yadong;Watanabe, Hiromi Kayama;Zhang, Ruiyan;Wang, Chunsheng	Chen, Chong, Zhou, Yadong, Watanabe, Hiromi Kayama, Zhang, Ruiyan, Wang, Chunsheng (2022): Neolepetopsid true limpets (Gastropoda: Patellogastropoda) from Indian Ocean hot vents shed light on relationships among genera. Zoological Journal of the Linnean Society 194: 276-296, DOI: 10.1093/zoolinnean/zlab081
884251566537FFC0FC5EA7AE0838FEFC.text	884251566537FFC0FC5EA7AE0838FEFC.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Neolepetopsis ardua Chen & Zhou & Watanabe & Zhang & Wang 2022	<div><p>NEOLEPETOPSIS ARDUA SP. NOV.</p> <p>(FIGS 2E, 5, 6)</p> <p>Z o o B a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org:act: 358436F9-1BAF-452D-A97A-935F1C36BEAC</p> <p>Diagnosis: Medium-sized Neolepetopsis (SL ≤ 5.1 mm) with stronger concentric sculpture compared with radial sculptures, intersecting points of which are weakly drawn out to form nodes. Concentric sculptures between 50 and 150 µm apart. Shell profile low, flat limpet-form, with apex on the midline and slightly anterior to the centre. Greenish periostracum present.</p> <p>Type locality: Apparently inactive sulfide deposits off the centre of venting activity at the Longqi hydrothermal vent field, Southwest Indian Ridge.</p> <p>Type material: Holotype (RSIO 49001; Fig. 2E), the only specimen collected with both intact shell and animal, in 95% ethanol, SL 5.1 mm, SW 3.7 mm, Longqi vent field, Southwest Indian Ridge, 49°38.88′E, 37°46.80′S, 2778 m deep (station ‘49I-S011-TVG04’), R / V Xiangyanghong 10, by video-guided grab sampler, 1 June 2018. Paratype 1 (NSMT-Mo 79219; Fig. 6), soft parts only, in 95% ethanol. Paratype 2 (RSIO 49010), soft parts only, in 95% ethanol. Paratype 3 (NSMT-Mo 79220), soft parts only, in 95% ethanol. Paratype 4 (RSIO 49011–49015), a lot of five individuals with soft parts only, in 95% ethanol. Paratype 5 (NSMT-Mo 79221), a lot of five individuals with soft parts only, in 95% ethanol. All paratypes are from the same lot as the holotype.</p> <p>Description: Shell (Fig. 2E) thin, translucent, thickest near apex; only known adult shell with length 5.1 mm, width 3.7 mm (length-to-width ratio 1.38:1). Shell thickness decreases towards shell edge, with increasing transparency, without significant prismatic structural coloration. Oval in outline; anterior end slightly narrower than posterior end (based on holotype). Shell profile low. Apex (Fig. 5A) situated on midline, slightly anterior of centre. Shell sculpture (Fig. 5B) finely reticulate, formed by strong, closely spaced (interspacing ranging from 50 to 150 µm on holotype) concentric ribs crossing weaker, frequent radial ribs. Weak, almost indistinct nodes drawn out at points where concentric and radial ribs cross. Muscle scar clearly discernible. Protoconch unknown; holotype with seal along opening of protoconch (Fig. 5A). Thin, greenish periostracal layer present over shell.</p> <p>Radula (Fig. 5C, D) with seven mineralized (rachidian, two pairs of laterals, pluricuspid) and four non-mineralized (two pairs of marginals) teeth per row, ~35 µm wide. Rachidian sturdy; base of long shaft slightly expanded laterally, tapering distally toward one overhanging, triangular cusp with smooth cutting edge. Laterals gradually descending in horizontal position outward. Inner laterals with minor indentation at base to accommodate expanded base, also with similar-sized overhanging, triangular, smooth cusp. Outer laterals with slightly studier shafts than inner laterals, carrying broader overhanging cusps. Pluricuspid teeth positioned much lower than laterals, with broad overhanging cusps with two sharp tips. Shafts of pluricuspids strongly basolaterally indented; sinuous shafts connecting to inner marginal. Inner marginals with broad, indented shaft; cutting edge broad. Outer marginals greatly reduced, with short, narrow shafts; cusps narrow. External anatomy (Fig. 6) similar to N. prismatica described above, but intestine packed with darker, black coloured faecal pellets.</p> <p>Etymology: From Latin adjective arduus, meaning high, steep, difficult or troublesome. It is named in witness of the arduous efforts, through numerous attempts that the authors had to make in preparing and mounting the minute radula of this Neolepetopsis species.</p> <p>Distribution: Known only from inactive chimney surfaces off the Longqi hydrothermal vent field on the Southwest Indian Ridge, Indian Ocean. The sulfide deposits from which the present new species was obtained were collected by a grab sampler and, as far as we could see from the video, they appeared inactive.</p> <p>Remarks: Only one specimen (the holotype) of N. ardua was collected intact with the shell and soft parts. Shells of all other specimens available for study have apparently been lost during the sampling process; some had a few shell fragments still attached, indicating that they were not shell-less when alive. All descriptions of shell characters are therefore based solely on the holotype.</p> <p>Neolepetopsis ardua is easily distinguished from the geographically closest species, N. prismatica, by its much stronger radial sculpture (compare Figs 3C, 5B) and the presence of drawn out nodes at the intersection between radial and concentric ribs. The shell shape of N. ardua is slightly wider at the posterior (based on the holotype), whereas that of N. prismatica is either wider at the anterior end or similar in width at both ends (Fig. 2). Furthermore, N. ardua does not possess the same level of iridescent structural colour on the shell interior seen on N. prismatica. The shell sculpture of N. ardua is generally similar to that of N. densata, N. verruca and N. occulta (McLean, 1990), but differs in that the axial ribs are much more frequent but weak in strength, leading to only insignificantly raised (as opposed to strongly raised) nodes being formed at the intersections. Neolepetopsis densata and N. occulta have fully transparent shells (McLean, 1990), whereas that of N. ardua is only translucent. The present new species is easily distinguished from both N. gordensis and N. nicolasensis by the concentric sculpture being stronger than the radial ones, and by the low shell profile and the much thinner, delicate shell. The radula of N. ardua is most similar to N. gordensis in having long shafts and possessing two cusps on the pluricuspid tooth (McLean, 1990), but the mineralized cusps are generally heavier than those in that species, and the marginals are more reduced in N. ardua.</p> </div>	http://treatment.plazi.org/id/884251566537FFC0FC5EA7AE0838FEFC	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Chen, Chong;Zhou, Yadong;Watanabe, Hiromi Kayama;Zhang, Ruiyan;Wang, Chunsheng	Chen, Chong, Zhou, Yadong, Watanabe, Hiromi Kayama, Zhang, Ruiyan, Wang, Chunsheng (2022): Neolepetopsid true limpets (Gastropoda: Patellogastropoda) from Indian Ocean hot vents shed light on relationships among genera. Zoological Journal of the Linnean Society 194: 276-296, DOI: 10.1093/zoolinnean/zlab081
88425156653AFFC0FC51A0D009F6FD2D.text	88425156653AFFC0FC51A0D009F6FD2D.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Eulepetopsis McLean 1990	<div><p>GENUS EULEPETOPSIS MCLEAN, 1990</p> <p>Type species: Eulepetopsis vitrea McLean, 1990 (by original designation).</p> <p>Diagnosis: Large (≤ 17 mm SL) neolepetopsid limpets with totally transparent shell, whose outer layer is constructed from lathic calcite. Shell profile low; shell surface almost completely smooth. Radula well developed and sturdy, including large inner marginals; outer marginal reduced to vestigial.</p></div> 	http://treatment.plazi.org/id/88425156653AFFC0FC51A0D009F6FD2D	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Chen, Chong;Zhou, Yadong;Watanabe, Hiromi Kayama;Zhang, Ruiyan;Wang, Chunsheng	Chen, Chong, Zhou, Yadong, Watanabe, Hiromi Kayama, Zhang, Ruiyan, Wang, Chunsheng (2022): Neolepetopsid true limpets (Gastropoda: Patellogastropoda) from Indian Ocean hot vents shed light on relationships among genera. Zoological Journal of the Linnean Society 194: 276-296, DOI: 10.1093/zoolinnean/zlab081
88425156653AFFC4FC49A2660881F951.text	88425156653AFFC4FC49A2660881F951.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Eulepetopsis crystallina Chen & Zhou & Watanabe & Zhang & Wang 2022	<div><p>EULEPETOPSIS CRYSTALLINA SP. NOV.</p> <p>(FIGS 7–9)</p> <p>ZooBank registration: urn:lsid:zoobank.org:act: 438E4525-BBA7-437B-BA48-A8E04481FE93</p> <p>Neolepetopsidae gen. sp. – Hashimoto et al., 2001: 720, table 1.</p> <p>Eulepetopsis – Van Dover et al., 2001: 821, table 2.</p> <p>Eulepetopsis sp. – Watanabe &amp; Beedessee, 2015: 207, table 16.1; Sun et al., 2020: 8, table 1; Kim et al., 2020: supplementary table 1.</p> <p>Eulepetopsis sp. ‘SWIR’ – Zhou et al., 2018: 7, table 1.</p> <p>‘An unnamed species known from the Kairei Vent Field’ – Warén et al., 2006: 83.</p> <p>Diagnosis: Typical-sized Eulepetopsis ≤ 14.0 mm SL. Radula with sturdy pluricuspid teeth carrying a clear lateral projection mid-shaft, in addition to a finely serrated cutting edge.</p> <p>Type locality: <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=70.04031&amp;materialsCitation.latitude=-25.320524" title="Search Plazi for locations around (long 70.04031/lat -25.320524)">On</a> active vent chimney, Kairei vent field, Central Indian Ridge, 25°19.2315′S, 70°2.4187′E, 2424 m deep.</p> <p>Type material: Holotype (NSMT-Mo 79222; Fig. 7A) fixed in 10% buffered formalin and stored in 70% ethanol, SL 8.4 mm, SW 6.0 mm, <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=70.04031&amp;materialsCitation.latitude=-25.320524" title="Search Plazi for locations around (long 70.04031/lat -25.320524)">Kairei</a> vent field, Central Indian Ridge, 25°19.2315′S, 70°2.4187′E, 2424 m deep, collected by suction sampler, R / V Yokosuka cruise YK16-E02, DSV Shinkai 6500 dive #1449, 13 February 2016. Paratype 1 (NSMT-Mo 79223; Fig. 7B), fixed in 10% buffered formalin and stored in 70% ethanol, SL 8.7 mm, SW 8.0 mm. Paratype 2 (NSMT-Mo 79224), 99% ethanol, used for DNA extraction and sequencing, SL 10.8 mm, SW 8.0 mm. Paratype 3 (NSMT-Mo 79225; Fig. 7C), fixed in 10% buffered formalin and stored in 70% ethanol, SL 8.3 mm, SW 5.8 mm. All paratypes are from the same lot as the holotype.</p> <p>Materials examined: <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=69.596596&amp;materialsCitation.latitude=-23.8777" title="Search Plazi for locations around (long 69.596596/lat -23.8777)">One</a> specimen (NSMT-Mo 79226; Fig. 7D), Edmond vent field, Central Indian Ridge, 99% ethanol, SL 11.8 mm, SW 8.6 mm, 23°52.6621′S, 69°35.7959′E, 3279 m deep, collected by suction sampler, R / V Yokosuka cruise YK16-E02, DSV Shinkai 6500 dive #1457, 26 February 2016, covered in thick sulfide layer, now removed, in part, to reveal shell surface. <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=63.9233&amp;materialsCitation.latitude=-27.8505" title="Search Plazi for locations around (long 63.9233/lat -27.8505)">Six</a> specimens (RSIO 35734; Fig. 7E), Tiancheng vent field, Southwest Indian Ridge, SL 11.2–14.1 mm, SW 8.2–11.0 mm, 63°55.398′E, 27°51.030′S, 2682 m deep, collected by a seven-function manipulator, R / V Xiangyanghong 9 cruise DY35, HOV Jiaolong dive 87, 23 December 2014. <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=60.53&amp;materialsCitation.latitude=6.36" title="Search Plazi for locations around (long 60.53/lat 6.36)">Three</a> specimens (RSIO 38215; Fig. 7F), Wocan vent field, Carlsberg Ridge, SL 10.5–14.0 mm, SW 7.5–10.2 mm, covered in thin layer of sulfide deposits, 60°31.8′E, 6°21.6′N, 2920 m deep, collected by a seven-function manipulator, R / V Xiangyanghong 9 cruise DY38, HOV Jiaolong dive 129, 14 March 2017.</p> <p>Description: Shell (Fig. 7) thin, fully transparent, with thin layer of periostracum where not corroded. Shell length oblong oval; slightly narrower at anterior end than posterior end, more so in larger specimens (Fig. 7E). Maximum known shell sizes at SL 14.0 mm, SW 10.2 mm. Shell profile low, flat, with margin almost aligned along one plane in smaller specimens, becoming more uneven in larger ones (Fig.7). Protoconch unknown; inner surface of protoconch sealed in specimens with lost protoconchs. Apex situated on midline anteriorly, about one-quarter of shell length from anterior edge. Shell surface almost completely smooth except for concentric growth lines (Fig. 7C); area near apex corroded, with uneven lines (Fig. 8A). Inner surface of shell showing muscle scars (Fig. 7B); area near apex surrounded by a series of pores going into interior of shell towards apex (Fig. 8B, C), seen as long radial streaks by transparency under optical microscopy (Fig. 7G). Zigzagged crystal edges visible on inner surface of shell with electron scanning microscopy (Fig. 8C).</p> <p>Radula (Fig. 8D) with sturdy rachidian and two laterals, pluricuspid tooth, two marginals on either side. Cusps not well mineralized. Rachidian well supported, with laterally expanded base; shaft of moderate length, slowly tapering apically, ending in narrow, triangular, overhanging cusp. Inner laterals with elongate, tapering triangular cusps on a solid shaft carrying strong indentation to accommodate lateral supports of rachidian tooth. Outer laterals about twice as broad as inner laterals; shafts with weak indentation to accommodate inner laterals, each carrying one prominent lateral projection near base. Pluricuspid robust, more than twice as wide as outer laterals, with prominent lateral, mid-shaft projection. Overhanging cusp of pluricuspid broad, with numerous fine serrations decreasing in strength outward. Laterals and pluricuspid decrease in cusp positions outward from the rachidian. Inner marginal well formed, as broad as pluricuspid, with narrow, smooth, semicircular, overhanging cutting edge. Second marginal vestigial, found slightly outside of inner marginal.</p> <p>Soft parts are shown in Figure 9. Cephalic tentacles simple conical, without appendages, elongate, tapered. No external evidence for eyes. Oral disc with muscular outer lip, surrounded by moderately developed labial lobe. Well-developed, dorsally arched jaw present, often seen projecting from mouth in preserved specimens. Sole of foot oval, large, with unciliated rim demarcated by deep groove from sole. Epipodium lacking. Shell muscle U-shaped, separated into numerous oblong muscle bundles along the posterior three-quarters of body, with length of bundles decreasing posteriorly. Mantle edge with numerous fine, presumably sensory papillae. Mantle cavity shallow, extending to slightly shy of one-third of body length. Heart monotocardian, with auricle anterior of ventricle (seen by transparency), located within pericardium on left mantle roof. Ctenidium lacking. Sexes separate; gonad located ventrally along mid-body, partly visible from dorsal view slightly posterior to pericardium. Left kidney minute; sizeable right kidney positioned at posterior of body. Urogenital papillae on right mantle roof on right side of anus. Intestine much wider anteriorly, looping twice before emerging at posterior end of body as rectum. Rectum runs towards anterior left before turning to anterior right and finally emerges on right mantle roof. Intestine and stomach entirely embedded within voluminous digestive gland, comprising numerous tubular structures. Operculum lacking.</p> <p>Etymology: From Latin crystallinum, crystal-like, named for its highly transparent shell.</p> <p>Distribution: Known from a number of hydrothermal vent fields across Carlsberg Ridge (Wocan field), Central Indian Ridge (Kairei and Edmond fields) and Southwest Indian Ridge (Tiancheng field). Given its distribution range from the examined materials, Eulepetopsis recorded at both Solitaire (Nakamura et al., 2012; Watanabe &amp; Beedessee, 2015) and Onnuri (Kim et al., 2020) fields are most likely additional records of this species.</p> <p>Remarks: Eulepetopsis crystallina is similar morphologically to E. vitrea, the only other known species in the genus, described from vents on the East Pacific Rise. Both have highly transparent shells and similar anatomical features (Fretter, 1990), but are separable based on radula morphology, most notably the pluricuspid teeth. In E. crystallina, the pluricuspid has a prominent mid-shaft projection, which is lacking in that of E. vitrea (McLean, 1990; Warén &amp; Bouchet, 2001). The finely serrated cutting edge is another feature not mentioned in E. vitrea; the pluricuspid teeth as a whole are much stronger and broader at the base in E. crystallina than in E. vitrea (McLean, 1990; Warén &amp; Bouchet, 2001). Shafts of all teeth in E. crystallina are also noticeably longer than in E. vitrea (Warén &amp; Bouchet, 2001).</p> <p>GENETIC SUPPORT</p> <p>The consensus tree for Patellogastropoda from phylogenetic reconstruction by Bayesian inference using first and second codon positions of a 472 bp alignment in the barcoding region is shown in Figure 10. Neolepetopsis prismatica was recovered as sister to N. ardua with strong support [Bayesian posterior probability (BPP) = 0.97], with the clade interpreted as genus Neolepetopsis. The three sequences of E. crystallina included, one from each mid-ocean ridge, were recovered as a fully supported clade corresponding to the new species. This was sister to E. vitrea, with the two species forming a strongly supported clade (BPP = 0.99) representing genus Eulepetopsis. Eulepetospsis was recovered as sister to Neolepetopsis with moderate support (BPP = 0.72), with this pair in turn being sister to a moderately supported (BPP = 0.85) Paralepetopsis containing two (undescribed) species. This means that Paralepetopsis was recovered in a basal position within Neolepetopsidae, which was recovered as a well-supported (BPP = 0.92) clade containing the three abovementioned genera.</p> <p>At the level of families within Patellogastropoda, all currently established patellogastropod families (Nakano &amp; Ozawa, 2007; Aktipis &amp; Giribet, 2010; Nakano &amp; Sasaki, 2011; Goffredi et al., 2017) were recovered as moderately to well-supported clades (BPP = 0.7–1.0), but all sister relationships between families were not well supported. Neolepetopsidae was recovered as sister to Lepetidae, but this relationship was not well supported (BPP = 0.52).</p> <p>The genetic distances (K2P distances), estimated using 472 bp of the COI gene, among neolepetopsid taxa with suitable data available are shown in Table 1. The genetic distance for the three specimens of E. crystallina included, one from each ridge system, was 0.21–0.85%. This is much lower than the distance between these and E. vitrea, which ranged between 9.79 and 10.30%. The genetic distance between N. prismatica and N. ardua was estimated at 5.54%, and that between the two undescribed Paralepetopsis species (Aktipis &amp; Giribet, 2010; Goffredi et al., 2017) was 12.26%. The average genetic distance between species assigned to the same genera was 9.59% (range 5.54–12.26%), and between species of different genera it was 13.95% (12.27–15.09%).</p> </div>	http://treatment.plazi.org/id/88425156653AFFC4FC49A2660881F951	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Chen, Chong;Zhou, Yadong;Watanabe, Hiromi Kayama;Zhang, Ruiyan;Wang, Chunsheng	Chen, Chong, Zhou, Yadong, Watanabe, Hiromi Kayama, Zhang, Ruiyan, Wang, Chunsheng (2022): Neolepetopsid true limpets (Gastropoda: Patellogastropoda) from Indian Ocean hot vents shed light on relationships among genera. Zoological Journal of the Linnean Society 194: 276-296, DOI: 10.1093/zoolinnean/zlab081
