Retusa waughiana Hedley 1899

Figs 71G, H, 74

Retusa waughiana Hedley, 1899: 482-483, text fig. 44.

TYPE MATERIAL. — Not examined.

TYPE LOCALITY. — Lagoon Beach, Funafuti, Tuvalu, South Pacific.

MATERIAL EXAMINED. — New Caledonia proper. BATHUS 1: stn DE 697, Passe de Hienghène, 20°34’S, 164°58’E, 570-650 m, 1 dd.

DISTRIBUTION. — Found in the tropical Indo-Pacific, from Tuvalu to southern Japan (Hori 2000c). Single specimen herein collected from New Caledonia (Fig. 74), in 570-650 m.

DESCRIPTION. — Shell morphology. Length 2 mm, width 1 mm (single specimen examined). Shell fragile, elongate, wider anteriorly and narrower posteriorly, with nearly parallel sides (Fig. 71G). Only 1 whorl visible, forming nearly the entire shell, except for the top of the spire, where 3 whorls are visible. Apex flat, not umbilicate (Fig. 71H), with the aperture lip ending at the same level. Protoconch globose, about 0.5 whorl and 150 Μm in diameter (Fig. 71H). Anterior end of the shell rounded. Aperture as long as the shell, wider anteriorly and narrowing abruptly at about 1/3 of its length. Columellar margin slightly thickened. Columella simple, with no folds. Umbilicus closed. Sculpture of a number of strong, simple spiral lines crossed by faint growth lines. Some of the growth lines are very conspicuous and separated by several thinner lines. These conspicuous lines are more marked near and on the apex, where they form a distinctive radial pattern. Colour uniformly pale brown.

Anatomy. Unknown. All shells collected lacked soft parts.

REMARKS. — The single specimen here examined matches the original description of Retusa waughiana by Hedley (1899) and subsequent redescription by Hori (2000c).

Retusa waughiana differs from Retusa famelica Watson, 1883 by having a shorter and more cylindrical shell and a flat, non-umbilicate apex.

Because the anatomy of this species is unknown, it is provisionally maintained in the genus Retusa until complete specimens become available for study.