Chlamys durhami Adegoke, 1969
ADEGOKE, O. S. 1969. Stratigraphy and paleontology of the marine Neogene formations of the Coalinga Region, California. University of California Publications, Bulletin of the Department of Geological Sciences, 80: 1-269 p., pls. 1-13. [p. 97, pl. 2, fig. 5]
«Chlamys durhami Adegoke, n. sp.
(PI. 2, fig. 5) Shell small, thin, equilateral, gently and evenly convex, slightly higher than long; anterior and posterior dorsal margins moderately long, about half length of shell, subequal and straight, merge into very convex ventral margin with broad angle; umbonal angle about 90°; cardinal area straight and long, about three-fourths length of shell; shell ornamented by about 20-22 dichotomously branching ribs; branching occurs at different levels along individual ribs; rib profile rounded near cardinal area, wide and flat-topped near ventral margin; shell surface sculptured by numerous faint incremental lines of growth; posterior ear short and inconspicuous; anterior ear long, sculptured by 4 or 5 axial riblets and nunlerous faint lines of growth; byssal notch deep.
Dimensions.— Holotype, length 14.9 mm, height 17.9 mm, thickness of valve 2.7 mm, length of cardinal area 11.0 mm.
Holotype.— UCMP no. 36615, locality D-1099. Occurrence.—Santa Margarita Formation: D-1099. Range.— Late Miocene. Remarks.--Chlamys durhami, n. sp. is closely similar in outline and ornamentation to Chlamys jordani Arnold from the upper Pliocene and Pleistocene of San Pedro and Santa Barbara. It may be readily distinguished from the latter by its smaller size, fewer ribs, wider interspaces between ribs and the fact that bifurcation of ribs begin much earlier in the new species than in Arnold's species.»
OLUWAFAYISOLA SYLVESTER ADEGOKE, 1969
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O. S. Adegoke, 1969, plate 2.
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