Hyalorisia profunda 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 : 417

Hyalorisia profunda Fassio, Bouchet & Oliverio new species

MOTU-9 ( Figs 3I , 6A )

Type material: Holotype: South China Sea, ZHONGSHA 2015, Stn CP4137 , 19°53 N, 114°25 E, 524–536 m, MNHN-IM-2013-59695 . One paratype: same locality as holotype, MNHN-IM-2013-59696 .

Material examined: Type and other material (MNHN-IM-2007-33806, MNHN-IM-2007-33828 and MNHN-IM-2013-44655).

Etymology: After the Latin adjective profundus, -a, -um, meaning deep, with reference to the fact that this species occurs at great depths.

ZooBank registration: urn:lsid:zoobank.org:act:668C5D77-6FAB-457D-A7D9-0F142DC12E49 .

COI-based diagnosis: Three diagnostic (autapomorphic) positions in the alignment: 52(G), 325(T) and 359(C).

Shell (data for holotype shown within parentheses): Size small to medium for the genus: length 6–9 (7) mm, width 4–6 (5) mm, height 2–3 (2) mm; thin, ellipsoidal to rounded, depressed; white shell surface with smooth yellowish periostracum; anterior margin rounded; protoconch of 1–1.1 (1.1) whorls, diameter of nucleus 0.1–0.21 (0.16) mm; teleoconch smooth except for distinct commarginal growth ridges; apertural margin thin, interior glossy white; lamella narrow, width 0.29–0.69 (0.4) mm.

Soft parts: Not examined; damaged by tissue clipping.

Host: Based on the field label, the holotype and paratype were attached to a Propeamussium sp.; at that station, the only propeamussiids collected were P. jeffreysii and P. caducum . Two specimens (MNHN-IM-2007-33806 and MNHN-IM-2007-33828) were found at the same station; these and specimens of P. caducum (MNHN-IM-2007-33805 and MNHN-IM-2007-33827, respectively) have consecutive registration numbers, and MNHN-IM-2007-33827 also has a mark on the shell that corresponds to the contour of the Hyalorisia specimen. Another Hyalorisia specimen (MNHN-IM-2013-44655) was found at a station where the only propeamussiid collected was P. caducum .

Distribution: So far known only from the South China Sea and the Philippines, at depths of 536–1,240 m.

Remarks: Hyalorisia profunda n. sp. was found syntopically with H. nanhaiensis n. sp. (MOTU-6) on the continental slope of the South China Sea (ZHONGSHA 2015: Stn CP4137).

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 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.