Azumapecten erici (Wiedey, 1928)
WIEDEY, L. W. 1928. Notes on the Vaqueros and Temblor formations of the California Miocene with descriptions of new species. Transactions of San Diego Society of Natural History, 5 (10): 95-182, pls. 9-21. [p. 137, pl. 16, fig. 1]
«Pecten (Chlamys) erici Wiedey, sp. nov.
Plate 16, figure 1 Shell of large size, subovoid in outline, subequivalve and equilateral, moderately inflated, with the right valve apparently the more convex. The anterior dorsal margin is not long and is straight to the extremity, where it is rounded to the basal margin. The latter portion of the shell is evenly and regularly rounded. Posterior dorsal extremity a little more sharply convexly curved than the corresponding anterior portion. Posterior dorsal margin short and nearly straight, or slightly concave in outline. Umbones narrow and very convexly inflated. The sculpturing on the left valve consists of about thirty prominent ribs, which are rounded and closely spaced. They curve irregularly and a few divide near the basal margins of the shell. The ribs exhibit incremental sculpture only near the basal margins of the disk. The right valve appears to have a few less ribs but is similarly sculptured. The anterior ear is small; the posterior ear is the more extended. The umbonal angle is less than 90 degrees. Length, 58 mm.; breadth, 65 mm.; thickness of the attached valves, about 20 mm.
Holotype: S.D.S.N.H. type collection, type number 27, collected from S.D.S.N.H. and L.S.J. U. locality 406. Collected from the west end of South Mountain where it is truncated by the Santa Clara River, in a grayish-green, firmly indurated sandstone, but a few feet above the river bed, two miles southwest of Santa Paula, Ventura County, California. L. Wm. Wiedey, collector ; Yaqueros formation, lower Miocene. Among the fossil Pectens this new species is most closely resembled by P. sespeensis, var. hydei Arnold,⁷⁶ but the latter is distinctive in possessing much longer anterior and posterior dorsal margins, which form a smaller umbonal angle. The varietal form is sculptured by nearly ten less ribs which are more subequal. The characteristic paired ribbing of P. sespeensis Arnold,⁷⁷ about nine pairs in all, readily serves to distinguish it from the new species, which shows many more individual ribs. Found associated with this new species were : Rapana imperialis Hertlein and Jordan, R. serrai Wiedey, sp. nov., Turritella inezana Conrad, Cardium vaquerosensis Arnold, Dosinia mathewsonii Gabb, Panope generosa Gould, Pecten sespeensis, var. hydei Arnold. This new species is named for Eric Knight Jordan whose untimely death deprived West Coast paleontology of a valued scientist.» ⁷⁶ Smithsonian Miscellaneous Collections, Vol. 50, Publication No. 1780, pl. 53, fig. 3, 1908. ⁷⁷ U.S. Geological Survey Professional Paper 47, p. 69, pl. 8, figs. 2, 2a, 3, 1906. |
L. W. Wiedey, 1928, plate 16.
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LIONEL WILLIAM WIEDEY, 1928