Pecten (Lyropecten) vaughani emigdioensis Wagner & Schilling, 1923
WAGNER, C. M. & K. H. SCHILLING. 1923. The San Lorenzo Group of the San Emigdio Region, California. University of California Publications, Bulletin of the Department of Geological Sciences, 14 (6): 235-276, pls. 43-50. [p. 253, pl. 45, fig. 2]
PECTEN (LYROPECTEN) VAUGHANI EMIGDIOENSIS, n. subsp.
Plate 45, figure 2 «Type.― No. 11417. CoIl. Invert. Pal. Univ. Calif. loc. 3234.
Shell small; equilateral; convex; slightly longer than high; base regularly rounded, dorsal margins slightly concave; left valve with 10 prominent ribs, rail-shaped and flat to rounded on top; interspaces nearly equal to ribs in width; bottoms rounded; surface of ribs and interspaces covered with very fine radial striae; incremental lines not prominent; anterior ear sculptured by 5 distinct riblets; byssal notch shallow; posterior ear (imperfect type) ornamented by 1 rounded and 3 sharp ribs. Dimensions: length, 23 mm.; height, 21 mm.; convexity of left valve, 5.5 mm. Comparisons.― This subspecies varies from P. vaughani Arnold¹² in having fewer ribs, which are more uniform in size, though the fourth and seventh from the posterior end are somewhat more prominent than the others, and in having fewer riblets on the anterior ear. Occurrence.― Only one specimen of this subspecies was found. It occurs in the middle zone of Monterey group. ¹² Arnold, Ralph, Prof. Paper 47, U. S. Geol. Surv., p. 81, pI. 23, figs. 3, 3a, and 3b.
CARROLL MARSHALL WAGNER & KARL HOWARD SCHILLING, 1923
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C. M. Wagner & K. H. Schilling, 1923, plate 45.
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