Pecten aletes 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. 8, pl. 2, fig. 1, 4]
1925 Pecten (Pecten) aletes Hertlein, 1925
L. G. Hertlein, 1925, plate 2.
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«Shell of medium size. Right valve moderately convex, ornamented by about 11 rather broad, flat-topped radiating ribs, which anteriorly and posteriorly decrease in size, each rib with one to four narrow, slight, radial sulcations; interspaces flat-bottomed, narrower than the ribs, occasionally bearing a tiny radiating riblet, the whole surface of valve sculptured by fine, close, concentric striae; ears subequal, marked by growth lines, but lacking all radial sculpture. Left valve slightly concave, with a pronounced depression toward the beak; about nine flattopped radial ribs, separated by interspaces about as wide as the ribs, the ribs and interspaces both covered by fine, sharp, concentric sculpture; ears subequal, and somewhat concave, ornamented only by fine incremental lines. Altitude 62 mm,; longitude 65 mm.; diameter of right valve approximately 13 mm. ; apical angle of right valve approximately 100°.
Type: Right valve, No. 44 (L.S.J.U. type collection), from Loc. 50 (L.S.J.U.), Rancho Refugio, north of San Jose del Cabo, Lower California; Paratypes: No. 45 (L.S.J.U. collection), and No. 1767 (C.A.S. collection), C. R. Swarts collector. Horizon not known; probably Upper Miocene or Lower Pliocene. Pecten aletes differs from P. bellus Conrad in the smaller number of ribs, which are finely sulcate. It differs from P. laqueatus Sowerby, from Japan, to which it is most closely related, in the fewer ribs; also in that the ears on the right valve of the present species appear to be straighter and not quite as arcuate as those of P. laqueatus.» LEO GEORGE HERTLEIN, 1925
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«Comments.— Pecten aletes has fewer wider ribs than other eastern Pacific Tertiary species. The right valve holotype has seven primary ribs that are wide, flat, slightly undercut, and separated by interspaces slightly narrower than the ribs at the ventral margin. Three secondary ribs are present on the anterior end of the shell and two on the posterior end. Some of the ribs have radial riblets and grooves, and the entire shell surface has slightly imbricated, concentric sculpture. The portion of the anterior auricle exposed has no riblets; the posterior auricle is missing. The left valve paratype has seven wide, flat ribs separated by slightly wider interspaces. A secondary rib appears in some of the interspaces near the ventral margin. The entire shell has imbricated, concentric lamellae. The posterior auricle has one small riblet; the anterior auricle none.
The ribs on P. aletes are fewer in number, broader, and flatter than on P. bellus. Geographic range.— Baja California Sur. Geologic range. — Pliocene. Occurrence in Baja California.— Salada Formation (Beal, 1948).» MOORE, E. J. 1984. Tertiary Marine Pelecypods of California: Propeamussidae and Pectinidae. United States Geological SurveyProfessional Paper, 1228-B: iv + B1-B112, figs. 1-2, pls. 1-42. [p. B67, B68]
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Pecten (Pecten) aletes Hertlein; E. J. Moore, 1984, Tertiary Marine Pelecypods of California, pl. 28, figs. 3, 4.
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