Leucosyrinx arcana (E.A. Smith, 1899 ), 2025

Kantor, Yuri I., Fedosov, Alexander & Puillandre, Nicolas, 2025, Revision of the Indo-Pacific species of the genus Leucosyrinx Dall, 1889 (Neogastropoda: Conoidea: Pseudomelatomidae), European Journal of Taxonomy 999, pp. 1-126 : 92-94

Leucosyrinx arcana (E.A. Smith, 1899) comb. nov.

Fig. 32C

Pleurotoma (Surcula) arcana E.A. Smith, 1899: 239 .

Pleurotoma (Surcula) arcana – Annandale & Stewart 1909: pl. 9 figs 6, 6a.

Comitas arcana – Powell 1969: 272 (23-284), pl. 219 figs 6–7, with query. — Tan & Islami 2021: 325, fig. 9a.

Type material

Syntypes

ANDAMAN ISLANDS • 1 spec.; off Andaman Is.; 13°17′15″ N, 93°10′ E; depth 185 ftm (= 340 m); ZSI, M 926 /1 • 1 spec.; off Travancore coast; 9°29′34″ N, 75°38′ E; depth 360 ftm (= 660 m); ZSI, M 926 /1 .

Remarks

Judging from the illustration in Annandale & Stewart (1909) the shell is rather similar to some of the molecularly confirmed species of Leucosyrinx , e.g., L. quinetae sp. nov. ( Fig. 24 ) and some specimens of L. luzonica ( Fig. 23 ). The position of the anal sinus, occupying the entire subsutural ramp, suggests the inclusion in Leucosyrinx rather than in Comitas and we transfer the species to Leucosyrinx .

Sysoev (1996: figs 46–47) illustrated two specimens from the Gulf of Oman and the Gulf of Aden, identified by him as Comitas paupera (see below), which are very similar to the type of L. arcana and probably belong to this species. These specimens were collected at significantly larger depths, 1890– 2000 m. This assumption is based only on the shell characters and needs confirmation by anatomical and molecular data.

Distribution

From Gulf of Aden to Andaman Is. and Indonesia from 340 to 2000 m.

Figures

Fig. 32. Types of species of Leucosyrinx Dall, 1889 known only from empty shells. A. L. aequatorialis Thiele, 1925, holotype, SL 13 mm (from Thiele 1925). B. L. anteridion (Watson, 1881) comb. nov., holotype, SL 22.1 mm (images by Aimee McArdle, NHMUK Photographic Unit). C. L. arcana (E.A. Smith, 1899) comb. nov., syntype, ZSI, M 926/1, SL 25.0 mm (from Annandale & Stewart 1909: pl. 9 fig. 6–6a). D. L. curviplicata (Sysoev, 1996) comb nov., holotype NHMUK 1993092, SL 32. 4 mm (images by Aimee McArdle, NHMUK Photographic Unit). E. L. eurina (E.A. Smith, 1899) comb. nov., paratype NHMUK 1904-6-15-139, SL 39 mm (photo courtesy of NHMUK). F. L. halicyria (Melvill, 1904) comb. nov., holotype, NHMUK 1905-7-14-49, SL 32.0 mm. G. L. julia Thiele, 1925, syntype, ZMB Mol 109379, SL 10.6 mm (photo courtesy of Museum für Naturkunde). H. L. pagodaeformis (Schepman, 1913) comb. nov, figured syntype, NATURALIS, ZMA.MOLL.137728, SL 28.7 mm (photo courtesy of K. Hasegawa). Shells not to scale.

Fig. 24. A–G. Leucosyrinx quinetae sp. nov. A–C. Holotype, MNHN-IM-2013-44303, SL 54.1 mm. D. MNHN-IM-2013-59550, South China Sea,1634–1683 m, SL 53.5 mm.E–F. MNHN-IM-2013-59550, South China Sea, 1634–1683 m, SL 59.9 mm. G. MNHN-IM-2013-59549, South China Sea, 1634– 1683 m, SL 54 mm. H. Leucosyrinx luzonica (Powell, 1969), holotype, USNM 238476, SL 42 mm. All shells at the same scale.

Fig. 23. A–H. Leucosyrinx luzonica (Powell, 1969). A–C. Holotype, USNM 238476, SL 42 mm (photo courtesy of USNM). D–F. MNHN-IM-2013-59559, off Taiwan Bank, 1634–1683 m, SL 39.1 mm. G. MNHN-IM-2009-13472, Philippines, 1456–1471 m, SL 26.6 mm. H. MNHN-IM-2009-13444, Philippines, 1762–1806 m, SL 23.1 mm. I. Leucosyrinx sp. 19, MNHN-IM-2007-42539, Solomon Is., 1250–1402 m, SL 26.8 mm. J–L. Leucosyrinx diomedea (Powell, 1969) comb. nov., holotype, USNM 239425, SL 49 mm (photo courtesy of USNM). All shells at the same scale.