Cyclopecten vimineus (Dijkstra & Gofas, 2004)
DIJKSTRA, H. H. & S. GOFAS. 2004. Pectinoidea (Bivalvia: Propeamussiidae and Pectinidae) from some northeastern Atlantic seamounts. Sarsia, 89: 33-78, figs. 1-22. [p. 51, fig. 13]
2004 Cyclopecten vimineus Dijkstra & Gofas, 2004
H. H. Dijkstra & S. Gofas, 2004, figure 13.
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«Type material
Holotype (lv), from Seamount 2, Stn DW250, MNHN; 2 paratypes (rv), same locality, MNHN. Type locality
Northeast Atlantic, Plato Bank, 33°12.60N 29°17.20W, 1500 m. Material examined
Irving and Cruiser Banks. Seamount 2: Stn DW222, 32°20.81N 28°15.66W, 1150 m, 1 v. Atlantis Bank. Seamount 2: Stn DW261, 34°22.37N 30°27.79W, 1190–1340 m, 1 v. – Stn DW262, 34°23.36N 30°29.06W, 1000–1160 m, 2 v. Plato Bank. Seamount 2: the type material. Distribution
Only known from the examined material. Description
Shell up to Ca 15 mm high, fragile, semitransparent to opaque, circular, slightly inequivalve, equilateral, auricles unequal in shape and size, umbonal angle Ca 110°, internal riblets lacking, diameter of prodissoconch 232 m (Fig. 13E), colour uniformly whitish or creamy. Left valve sculptured with regularly spaced, commarginal lamellae, commencing on the dissoconch. A delicate radial sculpture commences later and may be inconspicuous, but there are conspicuous radial lines of projecting scales at the intersection with the commarginal lirae. Coarse commarginal lamellae on the auricles, more developed on the anterior. Right valve quite smooth in the early growth stage, later with fine commarginal lirae, more closely set than on the left valve. Posterior auricle continuous with disc with delicate, very closely spaced, lamellae. Anterior auricle discontinuous with disc with four to six weak radial riblets and overrunning closely spaced, very coarse lamellae. Hinge line straight with the lamellae of the anterior auricles forming spinose projections over the hinge line and folding over it. Byssal notch moderately deep, byssal fasciole rather broad. Ctenolium lacking. Etymology
The Latin adjective describing basketry work made from osier, alluding to the external appearence of the left valve. Remarks
The present species closely resembles Cyclopecten capeverdensis Dijkstra & Goud, 2002, known from the Cape Verde Islands and the Canary Islands, in reticulate texture of the left valve (see Table 2). It differs in having a more oblong shape, a larger size (Ca 15 mm in height, C. capeverdensis Ca 7 mm), and a different commarginal sculpture of the left valve. Cyclopecten capeverdensis has more widely spaced commarginal lirae on the early part of the left valve dissoconch, and has distinct small tubercles on the commarginal lirae, which are lacking in C. vimineus. Cyclopecten leptaleus (Verrill, 1884), known from subtropical and tropical western Atlantic, is also similar, but smooth in early growth stages. Later, it has thicker and still closer set commarginal lamellae on the left valve, which have a ragged appearance due to projections at their intersection with numerous, fine radial lines, but do not show definite radial riblets nor radial lines of scales.» HENK H. DIJKSTRA & SERGE GOFAS, 2004
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