(Gould, 1850)

(Figs 2E, F; 3D)

Lucina vesicula Gould, 1850: 256; 1852: 414, pl. 36, fig. 525a, b.

Anodontia (Cryptophysema) vesicula – Taylor & Glover 2005: 317, fig. 35A-D.

TYPE MATERIAL. — Lectotype, 1 sh (USNM 427779) cited as holotype by Johnson 1964: 167 (inadvertent lectotype selection).

TYPE LOCALITY. — Tongatabu (Tonga Islands).

MATERIAL EXAMINED. — Koumac. 3 stn, 0-13 m, 8 v.

Touho. 2 stn, 0 m, 2 v, 2 live.

Lifou. 4 stn, 1-10 m, 7 v.

Chesterfield Islands. CHALCAL 1, stn DC 61, 21°42’S, 159°29’E, 50 m, 1 v.

CORAIL 2, stn DW 100, 19°06’S, 158°27’E, 40 m, 1 v. — Stn DW 117, 19°25’S, 158°32’E, 52 m, 1 v. — Stn DW 120, 19°25’S, 158°22’E, 56 m, 1 v.

Other New Caledonia. Île des Pins, Baie de Kuto, 22°38’S, 167°26’E, 20 v.

LAGON,stn 406, Grand Récif Sud, 22°39’S, 167°21’E, 24 m, 1 v. — Secteur de Nouméa, stn 1368, 22°24’S, 166°21’E, 10 m, 2 v. — Stn 1369, 22°25’S, 166°28’E, 12 m, 4 v.

Loyalty Islands. Ouvéa, lagoon, 3 m, 1 v.

DISTRIBUTION. — A wide-ranging species distributed throughout the IWP from the northern Red Sea, and northern Indian Ocean to Tonga in the Pacific (see Taylor & Glover 2005 for details).

DESCRIPTION

Medium sized, H to 44.5 mm, L to 48.2 mm, moderately inflated,T/L 0.30, sub-circular in outline H/L 0.91. Colour white or cream. Periostracum fibrous, buff; shell surface smooth with commarginal growth increments and halts.Umbones small. Lunule narrow, lanceolate, impressed, slightly scooped. Hinge short, thin, curved, edentulous. Ligament internal, slightly inset. Anterior adductor scar long, relatively straight, detached from pallial line for about 70% of length, at an angle of about 25°. Tracks of adductor muscle scars often visible on the shell interior. Interior of shell dull, sometimes with radial striations. Pallial line discontinuous, divided into many small scars (Fig. 2F).

REMARKS

Anodontia vesicula is similar in shape to A. ovum, and the species are frequently confused in museum collections, but A. vesicula is easily distinguished by the discontinuous pallial line.