Calliotropis eucheloides Marshall 1979
Creators: name: Herbert, David G.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Seguenziida
Eucyclidae
Calliotropis
Calliotropis eucheloides

description: Calliotropis eucheloides Marshall, 1979
Fig. 13A–C, G
Calliotropis eucheloides Marshall, 1979: 527, fig. 3a–c.
Type loc.: east of Chanter Islets, Raoul Island, Kermadec Islands, 366–402 m.
Calliotropis eucheloides – Vilvens 2006: 62, figs 24–27; 2007: 46, figs 138–155, 160, 161; 2020: 39, figs 17a–o, 18a–o; 2021: 108, fig. 7j–n. — Herbert 2015: 29.
Material examined
WALTERS SHOAL – slopes • 7 empty shells; stn DW4881; 33°16′ S, 43°50′ E; depth 377–382 m; 2 May 2017; MNHN • 1 living specimen; stn DW4885; 33°17′ S, 43°55′ E; depth 272–380 m; 3 May 2017; DNA tissue sample; MNHN-IM-2013-67238 • 10 + empty shells; stn DW4886; 33°17′ S, 43°56′ E; depth 573–582 m; 3 May 2017; MNHN • 10 + empty shells; stn DW4887; 33°17′ S, 43°57′ E; depth 599–640 m; 3 May 2017; MNHN • 1 living specimen; stn DW4887; 33°17′ S, 43°57′ E; depth 599– 640 m; 3 May 2017; DNA tissue sample; MNHN-IM-2013-67239 • 1 living specimen; stn DW4887; 33°17′ S, 43°57′ E; depth 599–640 m; 3 May 2017; DNA tissue sample, photographed alive; MNHN- IM-2013-67240 • 1 empty shell, juvenile; stn DW4889; 33°09′ S, 43°58′ E; depth 353–465 m; 3 May 2017; MNHN • 10 + specimens, some living; stn DW4890; 33°09′, 43°59′ E; depth 492–588 m; 4 May 2017; MNHN • 1 empty shell; stn DW4891; 33°12′ S, 44°01′ E; depth 650–653 m; 4 May 2017; MNHN • 12 specimens, some living; stn DW4892; 33°12′ S, 44°01′ E; depth 624–646 m; 4 May 2017; MNHN • empty shell, juvenile; stn DW4893; 33°16′ S, 43°58′ E; depth 623–629 m; 4 May 2017; MNHN • 1 empty shell; stn DW4896; 33°07′ S, 43°51′ E; depth 325–357 m; 5 May 2017; MNHN • 1 empty shell, juvenile; stn DW4898; 33°09′ S, 44°01′ E; depth 652–668 m; 6 May 2017; MNHN • 1 empty shell; stn CP4901; 33°09′ S, 44°01′ E; depth 647–672 m; 6 May 2017; MNHN • 2 empty shells; stn CP4903; 33°11′ S, 44°01′ E; depth 620–642 m; 7 May 2017; MNHN • 1 living specimen; stn DW4904; 33°11′ S, 44°01′ E; depth 652 m; 7 May 2017; DNA tissue sample; MNHN-IM-2013-67241 • 1 empty shell; stn DW4904; 33°11′ S, 44°01′ E; depth 652 m; 7 May 2017; MNHN.
Distribution
Widespread in the Indo-West Pacific (Vilvens 2007, 2021). In the south-western Indian Ocean, it has been recorded from north-western and southern Madagascar (Vilvens 2006, 2021) and the east coast of South Africa (Herbert 2015). On Walters Shoal it is known only from the slopes at depths of 357–652 m (live-collected material 380–652 m); dredged on substrata of coarse sand.
Remarks
As currently interpreted, this species is widespread and variable (Vilvens 2006, 2007, 2021). With records from off eastern South Africa and off western Madagascar, its occurrence on Walters Shoal is unsurprising. Vilvens (2006) noted that Madagascan shells were somewhat larger than south-western Pacific specimens and differed slightly in sculptural detail, but observed that South African specimens were more typical in size. Material from Walters Shoal appears to be intermediate (diameter up to 12.0 mm). I should also point out that whereas the columella denticle in south-western Pacific specimens is a single rounded entity (see figures in Marshall 1979; Vilvens 2007), in specimens from the south-western Indian Ocean this denticle is apically notched in mature specimens (Fig. 13A herein; Vilvens 2006: fig. 26; Herbert 2015: fig. 5d), sometimes appearing as two separate, but basally fused denticles. Molecular sequence data will be required in order to establish whether one or more species is involved.
The external anatomy of a living specimen photographed on board ship (Fig. 13G) was similar to that described for Calliotropis by Hickman & McLean (1990). The head-foot is mostly whitish, but the oral area and foot sole are pale apricot. The tip of the snout is greatly expanded laterally, forming trigonal, palp-like extensions. The cephalic lappets are small, the cephalic tentacles well developed and micropapillate, and the eyes large and black on stout stalks. The neck lobes are digitate, although the right one is smooth posteriorly. There are 4–5 well-developed micropapillate epipodial tentacles on each side, with smaller intermediaries, all of which have apricot-tinged epipodial sense organs at the base. A rehydrated specimen had what appeared to be a large post-ocular peduncle behind the right eyestalk (obscured in the living specimen).
description: Published as part of Herbert, David G., 2024, The Vetigastropoda (Mollusca) of Walters Shoal, with descriptions of two new genera and thirty new species, pp. 1-119 in European Journal of Taxonomy 923 on pages 24-25, DOI: 10.5852/ejt.2024.923.2445, http://zenodo.org/record/10727741