Cylichna sibogae Schepman, 1913

Valdés, Ángel, 2008, Deep-sea “ cephalaspidean ” heterobranchs (Gastropoda) from the tropical southwest Pacific, Mémoires du Muséum national d'Histoire naturelle 196, pp. 587-792 : 659-660

Cylichna sibogae Schepman, 1913

Figs 30D, E, 34

Cylichna sibogae Schepman, 1913: 472 , pl. 32, fig. 7.

TYPE MATERIAL . — Probably lost (could not be located at ZMA).

TYPE LOCALITY. — Sanana Bay , Sulawesi, Indonesia, 22 m [ Siboga : stn 193] .

MATERIAL EXAMINED. — Philippines. MUSORSTOM 2: stn DR 34, 13°28’N, 121°12’E, 155-167 m, 2 dd (Figs 30D, E) . — MUSORSTOM 3: stn CP 143, 11°29’N, 124°11’E, 205-214 m, 40 dd.

DISTRIBUTION. — Originally described from Sanana Bay , Sulawesi, Indonesia (Schepman 1913). Subsequently reported from Sumatra, Indonesia (Thiele 1925). Material herein collected in the Philippines (Fig. 34), in 167-205 m.

DESCRIPTION. — Shell morphology. Length 12 mm, width 4 mm (largest specimen examined). Shell solid, elongate, with nearly parallel sides (Fig. 30D). Only 1 whorl visible, forming nearly the entire shell. Apex rounded, with a narrow umbilicus covered by the columellar margin (Fig. 30E), and the aperture lip rising from the centre. Anterior end of the shell rounded. Aperture as long as the shell, wider anteriorly and narrowing gradually at about 1/7 of its length. Columellar margin conspicuously thickened. Umbilicus closed. Sculpture of a number of faint irregular spiral lines. Colour uniform pale grey.

Anatomy. Unknown. All shells collected lacked soft parts.

REMARKS. — The material here examined matches the original description of Cylichna sibogae by Schepman (1913). Unfortunately the type material is probably lost (it could not be located at ZMA), but the drawings in the original description are good enough to allow a positive identification.

Cylichna sibogae is provisionally maintained in the genus Cylichna until complete specimens become available for study.