Argopecten antonitaensis (Durham, 1950)
DURHAM, J. W. 1950. Megascopic paleontology and marine stratigraphy. In: 1940 E. W. Scripps Cruise to the Gulf of California, Part. II. Geological Society of America Memoir 43: 1-216, pls. 1-48. [p. 62, pl. 9, figs. 1, 5]
1950 Aequipecten antonitaensis Durham, 1950
J. W. Durham, 1950, plate 9.
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«Shell small, resembling A. percarus (Hertlein); moderately convex, nearly equivalved; ornamented by 22 moderately high, rounded ribs with nearly vertical sides; on right valve interspaces about half as wide as ribs, on left valve equal in width to ribs; radial ribs crossed by fine concentric growth lines; extreme lateral margins smooth; hinge line 0.6 length of shell; ears unequal, elongate, anterior slightly longer than posterior; a large byssal notch in right valve; anterior ear of left valve decidedly alate; posterior ears slightly drawn out; anterior ear with about 7 radial ribs, posterior ear with about 8.
Dimensions of holotype: Length 41.8 mm, height 41 mm, length of hinge line 25 mm. Holotype: Calif. Acad. Sci. Paleo. Type Coll. no. 5957, paratypes Univ. Calif. Mus. Pal. nos. 30472, 30473; all from C.A.S. loc. 795. OCCURRENCE: C.A.S. loc. 795. RANGE: middle Pliocene. REMARKS: The long narrow anterior ear with that of the left valve being drawn out is very characteristic. The ears suggest A. percarus (Hertlein) but are longer in proportion to length of shell. It is also similar to some specimens of A. impostor (Hanna) but may be separated by the more produced posterior ears of the present species». JOHN WYATT DURHAM, 1950
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