Dimya molokaia Dall, Bartsch & Rehder, 1938

Raines, Bret & Huber, Markus, 2012, 3217, Zootaxa 3217, pp. 1-106 : 28-31

Dimya molokaia Dall, Bartsch & Rehder, 1938

Figures 13 E–I, 14 A–D

Dimya molokaia Dall et al., 1938: p. 79 , pl. 19, figs. 3.

Dimya molokaia Dall et al., 1938 — Severns 2011: p. 454, pl. 207, fig. 1.

Anomia sp. — DiSalvo et al., 1988: p. 459.

Material examined. Several single valves (3 to 6 mm) from EI (BK), the ‘ Anomia sp. ’ specimen recorded by DiSalvo et al. (1988) (BK) and the Hawaiian USNM holotype of D. molokaia .

Diagnosis. Shell small, irregularly orbicular, inequivalve, rather fragile. RV firmly attached to the substrate, no byssal foramen. LV slightly more inflated. Sculpture of commarginal lamellae. Supradorsal fusing present above the umbones. Prodissoconch, P 1 somewhat erroded, P2 well defined, round, smooth with the exception of growth striae, ca. 270 µm length and 250 µm height. Interior of adult valves with coarse radial fluting toward the margins. Two distantly placed elongate muscle scars, with the posterior bilobed. White to yellowish white in color .

Remarks. After studying Malchus’ (2000a) work on the early shell stages of a Dimyidae species, this species as well as the next had to be examined more closely. The supradorsal fusing at the umbones ( Fig. 13 I), the distant, elongate and unequal posterior and anterior muscle scars ( Figs. 13 D & G) of the EI material are consistent with Dimyidae . The EI specimens conform well to the Hawaiian USNM holotype of D. molokaia ( Figs. 14 A–D). The ‘ Anomia sp. ’ recorded by DiSalvo et al. (1988) is not Anomia species at all, but it is consistent in being a very juvenile example of D. molokaia .

Habitat. Occasionally found at several locations around EI, in sand, from 30–80 m.

Distribution. Dimya molokaia was previously only known from the Hawaiian Islands, but has now been extended to Easter Island— E2.