Cyclopecten pellucidulus Dijkstra, 1995
DIJKSTRA, H. H. 1995. Bathyal Pectinoidea (Bivalvia: Propeamussiidae, Entoliidae, Pectinidae) from New Caledonia and adjacent areas. In: Bouchet, P. (Ed.), Résultats des Campagnes MUSORSTOM, Volume 14. Mémoires du Muséum national d'Histoire naturelle, 167: 9-73, figs. 1-154 [p. 43, Figs. 65-68]
1995 Cyclopecten pellucidulus Dijkstra, 1995
H. H. Dijkstra, 1995, figures 63-70.
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«TYPE MATERIAL. — Holotype MNHN. Paratypes: 1 HD, 2 MNHN.
TYPE LOCALITY. — South of New Caledonia, BIOCAL, stn DW 51, 23°05' S, 167°44' E, 680-700 m.
MATERIAL EXAMINED. — Only known from the type material.
DISTRIBUTION. — Only known from the type locality, northern Norfolk Ridge, alive in 680-700 m.
DESCRIPTION. — Shell small, fragile, pellucid, suborbicular, inequivalve, up to ca. 6 mm high, left valve slightly more convex than right, auricles equal in size, umbonal angle ca. 125°
Prodissoconch ca. 230 μm in height. Left valve covered with curved concentric lamellae, commencing at 2 mm shell height, enlarging towards ventral margin. Umbonal area smooth and glossy. Auricles with close-set concentric lamellae. Right valve covered with delicate regularly spaced concentric lirae that gradually enlarge, interspaces with microscopic radial scratches. Anterior avricle with concentric lamellae, stronger than on posterior auricle, strongly developed scales on antero-dorsal margin. Exterior sculpture visible from interior of both valves. Interior with one weak liration on the inner side of each auricle. Resilifer triangularly elongate. Byssal notch present, no ctenolium. Outer ligament small. Dimensions of the holotype: H 6.1, H 6.8, D 1.2 mm. REMARKS. — A somewhat similar species is Cyclopecten aupouria Powell, 1937 flom northern New Zealand, which attains larger size, is more convex, and is opaque white with more delicate concentric lirae and finer radial lirae. Another related species is C. bavayi Dijkstra, 1990 from the Ceram Sea (Indonesia), which is also slightly larger, opaque, and covered with numerous concentric lamellae on the early disc, and small radial riblets, which are absent in C. pellucidulus.
ETYMOLOGY. — From the translucence of the shell (Latin pellucidulus, adj. = translucent).»
HENK H. DIJKSTRA, 1995
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