3217
Author
Raines, Bret
Author
Huber, Markus
text
Zootaxa
2012
2012-02-29
3217
1
106
journal article
11755334
Dimya mimula
Dall, Bartsch & Rehder, 1938
Figures 13 C–D
,
14 E–F
Dimya mimula
Dall
et al
., 1938
: p. 78
, pl. 19, figs. 1–2.
Dimya mimula
Dall
et al
., 1938
—
Severns 2011
: p. 454
, pl. 207, fig. 2.
Material examined.
Several single valves (
4.5 to 6 mm
) from
EI
(BK), plus the Hawaiian USNM
holotype
of
D. mimula
.
Diagnosis.
Shell small, orbicular-elongate, inequivalve. RV attached to the substrate, no byssal foramen. LV sculptured with somewhat scaly radial riblets. Prodissoconch somewhat worn, but appears round and smooth.
Interior
of adult valves with finely denticulate margins. Two distantly placed elongate muscle scars, with the posterior bilobed. Yellowish white outside, whitish inside.
Remarks.
Dimya mimula
is an exceedingly rare species. As far as is known, this is the first time it has been recorded since its description from a single upper valve collected from a depth of
235 m
.
The upper valves of the
EI
specimens match the USNM
holotype
of
D. mimula
(
Figs. 14 E–F
) well and the largest valve (
13.8 mm
) also reaches nearly its
14 mm
size. The radial surface sculpture is characteristic for this species. The bilobed posterior scars are well visible (
Figs. 13 D
,
14 F
). The rounded contour, yellowish color and notably the characteristic dense crenulations along the outer margins (
Fig. 13 D
) are all consistent with
D. mimula
.
Habitat.
Occasionally found at several locations around
EI
, in sand, from
30–80 m
.
Distribution.
Dimya mimula
was previously only known from the Hawaiian Islands, but has now been extended to Easter Island—
E2
.