Cyclopecten benthalis Grau, 1959
GRAU, G. 1959. Pectinidae of the eastern Pacific. Allan Hancock Pacific Expeditions, 23: viii, 308 p., pls. 1-57. University of Southern California Press. Los Angeles, California. [p. 24, pl. 5]
1959 Cyclopecten benthalis Grau, 1959
G. Grau, 1959, plate 5.
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«Shell quite small, translucent, very slightly higher than long, and equivalve; hinge line about half as long as disk and beaks protruding slightly. Right valve flatly convex, with reflexed ventral margin (about 1/5 total height of valve); numerous faint concentric ridges and, along ventral margin, numerous even fainter radial ridges. Anterior auricle longer than posterior, concentrically lamellose and with 3 distinct radial ridges; byssal notch shallow and no ctenolium. Posterior auricle small, with perpendicular margin and covered by fine concentric lamellae. Left valve moderately convex and radially corrugated, resulting in 13 low primary ridges with a few irregularly disposed secondary ridges between some of them, 9 secondary ridges adjoining anterior submargin and 7 adjoining posterior; minute subglobular vesicles on primary ridges, about ½ mm apart. Auricles of same size as corresponding ones of right valve; both with fine concentric lamellae and 6 very faint radial ridges.
Holotype: Height 8 mm; length 7.5 mm; diameter 1.75 mm; hinge line 3.9 mm; only specimen known. AlIan Hancock Foundation. Type locality: 14.5 miles NNW of San Nicolas Island, California, in 490 fathoms, gray-green mud, tubiculous annelids, foraminiferans, Phyllochaetopterus sp.; Hancock station 3031-55 ; 33°28'04"N, 119°34'41"W; May 7,1955. Remarks; Although it is seldom advisable to describe a new species on the basis of a single specimen, the author feels justified in this instance. The short hinge line and the ridges and sculpture of the left valve distinguish this species from any other Pacific Cyclopecten. In general aspect it resembles the Atlantic C. imbrifer (Loven) (1847, p. 185), but that species differs in having larger anterior auricles with more numerous radial ridges, imbricated posterior auricles, no fine radial ridges on the right valve and more numerous and more profusely sculptured radial ridges on the left valve.» GILBERT GRAU, 1959
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