Genus Myrtina n.gen.

TYPE SPECIES. — Myrtina porcata n. sp. (here designated).

ETYMOLOGY. — Myrtina diminutive of Myrtea .

DIAGNOSIS. — Shells small to medium in size, relatively flat, sub-circular, dorsal anterior margin with more or less elevated commarginal lamellae. Sculpture of fine to prominent, closely spaced, commarginal lamellae. Radial ribs absent. Lunule lanceolate to heart-shaped, asymmetric with larger part in right valve. Two cardinal teeth in left valve and single tooth in right valve; indistinct lateral teeth present in both valves. Anterior adductor scar short, detached for about 1/5 of length. Pallial line entire. Shell margin smooth.

REMARKS

Alucinoma Habe, 1958 is similar in outline to Myrtina n. gen. but the type species, A. soyae Habe, 1958, from Japan, lacks hinge teeth and the thin commarginal lamellae are prominent largely on the posterior and anterior dorsal margins of the shell.