Hyalorisia neocaledonica Fassio, Bouchet & Oliverio, 2020

Fassio, Giulia, Russini, Valeria, Buge, Barbara, Schiaparelli, Stefano, Modica, Maria Vittoria, Bouchet, Philippe & Oliverio, Marco, 2020, High cryptic diversity in the kleptoparasitic genus Hyalorisia Dall, 1889 (Littorinimorpha: Capulidae) with the description of nine new species from the Indo-West Pacific, Journal of Molluscan Studies (Rijksuniversiteit te Gent. Fakulteit van de Landbouwkundige en Toegepaste Biologische Wetenschappen) 86 (4), pp. 401-421 : 414

Hyalorisia neocaledonica Fassio, Bouchet & Oliverio new species

MOTU-2 ( Figs 3B , 4B , 6D , 7B, K )

Type material: Holotype: Lord Howe Rise, W of New Caledonia, KANADEEP 1, Stn CP5000 , 23°57 S, 161°47 E, 985– 1,050 m, MNHN-IM-2013-65645 (male?). Eight paratypes: same locality as holotype; MNHN-IM-2013-65642 (female?), MNHN-IM-2013-65643 (female), MNHN-IM-2013-65644 (female?), MNHN-IM-2013-65646 (male), MNHN-IM-2013-65647 (male), MNHN-IM-2013-65865 (female), MNHN-IM-2013-65883 (female?) and MNHN-IM-2013-65909 (male?).

Other material examined: MNHN-IM-2007-37029, MNHN-IM-2013-48364, MNHN-IM-2013-48706, MNHN-IM-2013-48842, MNHN-IM-2013-48852, MNHN-IM-2013-65868, MNHN-IM-2013-65869, MNHN-IM-2013-65870, MNHN-IM-2013-65871 and MNHN-IM-2013-65907.

Etymology: From the general area of the type locality, New Caledonia.

ZooBank registration: urn:lsid:zoobank.org:act:01FE7631-F5E1-42D6-8B09-8C3DA1BB7627 .

COI-based diagnosis: Six diagnostic (autapomorphic) positions in alignment: 112(C), 121(G), 364(G), 451(G), 454(G) and 466(G).

Shell (data for holotype shown within parentheses): Size medium to large for genus: length 7.5–17.5 (9.5) mm, width 5.6–10 (7) mm, height 2.32–7.28 (3.04) mm; thin, ellipsoidal, ovoidal or rounded and depressed; white surface with a smooth yellowish periostracum; anterior margin rounded or very slightly angled; protoconch of 1–1.2 (1) whorls, diameter of nucleus 0.1–0.2 (0.2) mm; teleoconch smooth except for distinct commarginal growth ridges; apertural margin thin, interior glossy white; lamella wide, width 0.8–1.64 (1.28) mm.

Soft parts (ethanol preserved): Head, cephalic tentacles, mantle and foot whitish; pseudoproboscis whitish, sometimes with grey speckles along the dorsal margins.

Radula: Taenioglossate, 2-1-R-1-2; marginal teeth sickle shaped; lateral teeth triangular, outer and inner edges with few denticles; rachidian tooth triangular, denticulated on both edges.

Host: No direct records. One Hyalorisia specimen (MNHN-IM-2007-37029) was found at the same sampling station as a specimen of P. investigatoris (MNHN-IM-2007-37028); note the consecutive registration numbers.

Distribution: So far known only from New Caledonia, at depths of 330–1,060 m.

Remarks: Grey speckles were observed along the dorsal margins of the pseudoproboscis of 5 of the 19 specimens examined. So far, this is the only species of this genus showing this feature.

Figures

Figure 3. Protoconchs of Hyalorisia. A. Hyalorisia galea, MNHN-IM-2013-61536. B. Hyalorisia neocaledonica n. sp., MNHN-IM-2013-65907. C. Hyalorisia tosaensis, MNHN-IM-2007-34794. D. Hyalorisia nupta n. sp., MNHN-IM-2007-34005. E. Hyalorisia lehibe n. sp., MNHN-IM-2007-39212. F. Hyalorisia nanhaiensis n. sp., MNHN-IM-2013-34796. G. Hyalorisia kely n. sp., MNHN-IM-2007-38809. H. Hyalorisia melanesica n. sp., MNHN-IM-2013-58359. I. Hyalorisia profunda n. sp., MNHN-IM-2007-33828. J. Hyalorisia madagascarensis n. sp., MNHN-IM-39292. K. Hyalorisia solomonensis n. sp., MNHN-IM-2007-34215. Scale bars = 100 µm.

Figure 4. Shells of Hyalorisia. A. Hyalorisia galea, MNHN-IM-2013-60195, N of Grande-Terre, Guadeloupe (L = 13 mm). B. Hyalorisia neocaledonica n. sp., holotype, MNHN-IM-2013-65645, Lord Howe Rise, New Caledonia (L = 9.5 mm). C. Hyalorisia tosaensis, MNHN-IM-2013-58352, New Ireland, Papua New Guinea (L = 15 mm). D. Hyalorisia nupta n. sp., holotype, MNHN-IM-2007-34010, Bellona Reefs, New Caledonia (L = 18.5 mm). Scale bars = 2 mm.

Figure 6. Shells of Hyalorisia (A–C) and detail of the lamella (D, E). A. Hyalorisia profunda, holotype, MNHN-IM-2013-59695, South China Sea (L = 7 mm). B. Hyalorisia madagascarensis n. sp., holotype, MNHN-IM-2007-39090, off Mahajanga, Madagascar (L = 6.5 mm). C. Hyalorisia solomonensis n. sp., holotype, MNHN-IM-2007-34203, SE of Santa Isabel, Solomon Islands (L = 8 mm). D. Wide lamella of Hyalorisia neocaledonica n. sp., MNHN-IM-2013-65645, Lord Howe Rise, New Caledonia. E. Narrow lamella of Hyalorisia tosaensis, MNHN-IM-2013-58352, New Ireland, Papua New Guinea. Scale bars = 2 mm.

Figure 7. Radulae of Hyalorisia (A–I) and detail of the rachidian tooth (J–R). A, J. Hyalorisia galea MNHN-IM-2013-60195. B, K. Hyalorisia neocaledonica n. sp., MNHN-IM-2013-65647. C, L. Hyalorisia tosaensis, MNHN-IM-2013-58352. D, M. Hyalorisia nupta n. sp., MNHN-IM-2013-68952. E, N. Hyalorisia nanhaiensis n. sp., MNHN-IM-2013-59697. F, O. Hyalorisia kely n. sp., MNHN-IM-2007-38809. G, P. Hyalorisia melanesica n. sp., MNHN-IM-2007-34205. H, Q. Hyalorisia madagascarensis n. sp., MNHN-IM-2007-39090. I, R. Hyalorisia solomonensis n. sp., MNHN-IM-2007-34215. Scale bars = 100 µm.