Euvola lecontei (Arnold, 1906)
ARNOLD, R. 1906. The Tertiary and Quaternary pectens of California. United States Geological Survey Professional Paper, 47: 1-264, pls. 1-53. [p. 98, pl. 33, figs. 4, 4a, 4b]
1906 Pecten (Pecten) lecontei Arnold, 1906
R. Arnold, 1906, plate 33.
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«Descrlption.— Shell averaging about 60 millimeters in altitude, longer than high, plano-convex, equilateral, and with smooth margins; base evenly rounded; sides concave above. Right valve convex, and ornamented by about 18 prominent round-topped, peipendicular-sided, smootliish ribs, separated by interspaces, which are narrower than the ribs and have nearly flat bottoms; surface sculptured by fine wavy incremental lines, which are generally worn off from the tops of the ribs; hinge less than one-half the length of the disk; ears somewhat convex; the anterior with 2 or 3 broad, nearly obsolete, radiating ridges, imbricating incremental lines, and a rather small byssal notch; the posterior rectangularly truncated, and with fine incremental sculpture. Left valve flat or slightly concave, ornamented by about 17 prominent rounded ribs, which are separated by interspaces about equal in width to the ribs; surface sculptured by numerous fine, sharp, regular, raised, incremental lines; ears concave, rectangularly truncated, and covered by fine sharp incremental lines.
Dimensions.— Alt. 59 mm.; long. 65 mm.: hinge line 29 mm.: diameter 18 mm.; umbonal angle (left valve) 102°. This species is distinguishable from P. diegensis, P. bellus, P. stearnsii and other members of this group by the number and convexity of the ribs on the right valve. The left valves of P. lecontei and P. diegensis are somewhat similar, although the former has fewer ribs and is generally slightly more concave. P. lecontei has so far been found only in the Pliocene of Cerros Island, where it is associated with P. veatchii, P. cerrosensis, and Ostrea veatchii. The type is now in the collection of Delos Arnold. Named in honor of the late Prof. Joseph Le Conte, of the University of California. RANGE.
Pliocene. Cerros Island, Lower California (University of California).»
RALPH ARNOLD, 1906
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