Argopecten ventricosus calli (Hertlein, 1925)
HERTLEIN, L. G. 1925. Pectens from the Tertiary of Lower California. Proceedings of the California Academy of Sciences [4th Series], 14 (1): 1-35, pls. 1-6. [p. 16, pl. 4, figs. 5-7]
1925 Pecten (Plagiotecnium) calli Hertlein, 1925
L. G. Hertlein, 1925, plate 4.
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«Shell small, inequivalve. Right valve slightly arched, ornamented by about 16 or 17 rather high, narrow, rounded, radiating ribs separated by interspaces of about the same width as the ribs; anterior ear with a large byssal notch and sculpture consisting of about five radiating riblets crossed by concentric lines of growth; posterior ear sculptured by radiating riblets crossed by concentric lines of growth. Left valve slightly prolonged posteriorly, much more highly arched than right, and sloping rather abruptly from the umbos, sculptured by about 19 well developed, rather sharp, rounded, radiating ribs separated by interspaces about as wide as the ribs, ribs and interspaces crossed by fine concentric lines; ears slightly concave, the anterior with a small notch and ornamentation consisting of five or six radiating riblets crossed by concentric lines of growth; posterior ear slightly prolonged at the hinge line, sculptured as right. Altitude 24 mm.; longitude 24 mm.; diameter of left valve approximately 7 mm.; apical angle approximately 90º.
Type: Left valve. No. 68 (L.S.J.U. type collection), from Loc. 53 (L.S.J.U.), first arroyo east of Santiago, Lower Cailifomia, C. R. Swarts collector; Miocene? Paratype: No. 125 (L.S.J.U. collection), same locality as the type; also No. 126 (L.S.J.U. collection), from Loc. 63 (L.S.J.U.), intersection of Arroyo Fortuna with Arroyo Refugio, near San Jose del Cabo, Lower California, C. R. Swarts collector; also No. 127 (L.S.J.U. collection) from Loc. 60 (L.S.J.U. collection), west side of Elephant Mesa, Scammon Lagoon Quadrangle, Lower California, B. F. Hake collector; Isidro formation. Lower Miocene; also No. 1772 (C.A.S. collection), from Turtle Bay, Lower California, E. C. Johnson collector; Pliocene. Pecten calli differs from P. andersoni Arnold, in its narrower ribs and more highly arched left valve. From P. discus Conrad, and P. raymondi Clark, the present species is distinguished by the differently shaped ribs and less circular outline of the valves. From P. deserti Conrad and P. impostor Hanna, P. calli is distinguished by its high narrow, rounded ribs and only slightly arched right valve. From P. santarosanus Böse, P. calli is distinguished by the fewer higher ribs and by the presence of a profound rounded notch in the posterior ear of the left valve of the present species, which notch is lacking in P. santarosanus. This species is named in honor of Mr. E. Call Brown, whose cohection has added to the knowledge of the stratigraphy of Lower California.» LEO GEORGE HERTLEIN, 1925
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