Anodontia (Pegophysema) philippiana (Reeve, 1850)

(Figs 2A, B; 3A)

Lucina philippiana Reeve, 1850: pl. 5, fig. 23a, b.

Anodontia philippiana – Chavan 1938: 124.

TYPE MATERIAL. — 3 syntypes (BMNH 1963122/123).

TYPE LOCALITY. — Unknown.

MATERIAL EXAMINED. — Touho. 3 stn, 0-4 m, 2 v, 1 live.

Other New Caledonia. Hienghène, mission d’Ouavé, 20°41’S, 164°56’E, intertidal, 20 v.

DISTRIBUTION. — Wide ranging across the IWP, from Red Sea and East Africa, through south east Asia and northern Australia to New Caledonia and Palau Islands (Taylor & Glover 2005: fig. 22). Usually lives deeply burrowed (up to 50 cm deep) in intertidal and shallow subtidal muds and sands along the seaward fringe of mangroves.

DESCRIPTION

Shell large but thin and light-weight, H to 60.0 mm, L to 71.0 mm, inflated (T/L 0.30). Outline subcircular, shell longer than high (H/L 0.89). Periostracum thick, dull brown, fibrous. Shell colour creamy or greyish white.Sculpture of many irregular, rounded, commarginal lamellae or ridges. Lunule short, heart-shaped, symmetrical. Hinge plate thin, edentulous and smooth. Ligament largely internal; inner fibrous layer of ligament extends laterally and posteriorly into the valve forming a thick, triangular pad within narrow ligamental nymph. Anterior adductor muscle scar relatively broad and short, blunt ended; diverges from pallial line at an angle of 30-34°. Pallial line entire, narrow. Secondary pallial muscle scars extend from the junction of the pallial line and anterior adductor scar to just ventral of the posterior adductor scar (Fig. 3A).

REMARKS This is the largest of the Anodontia species from New Caledonia. Often referred to as Anodontia edentula in literature (e.g., Sotto & Cosel 1982; Lebata 2000).