Euvola beali (Hertlein, 1925)
HERTLEIN, L. G. 1925. Pectens from the Tertiary of Lower California. Proceedings of the California Academy of Ciences [4th Series], 14 (1): 1-35, pls. 1-6. [p. 10, pl. 2, fig. 3; pl. 5, fig. 8]
1925 Pecten (Pecten) beali Hertlein, 1925
Leo G. Hertlein, 1925, pls. 2, 5.
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«Shell inequivalve, plano-convex, equilateral, the ventral margin evenly rounded. Right valve convex, ornamented by about 23 or 24 prominent, square, flat-topped, strongly medially sulcate radial ribs, with in some cases, fainter radial grooves superimposed; interspaces flat-bottomed and slightly narrower than the ribs, the whole surface sculptured by fine, regular, concentric lines; posterior ear sculptured by about four radial riblets, and by fine incremental lines. Left valve flat or slightly concave, ornamented by about 21 radiating ribs separated by flat-bottomed interspaces, each of which bears a single small intercalated riblet, the ribs and interspaces crossed by fine concentric lines; a somewhat depressed area is found just below the beak; margins of shell somewhat concave, bearing four or five radiating ribs and fine concentric imbricating lines; ears somewhat concave, ornamented by three or four radiating riblets and by fine concentric lines of growth. Altitude 55 mm.; longitude 56 mm.; diameter of right valve approximately 10 mm.; apical angle of right valve approximately 114°.
Type: Right valve, No. 55 (L.S.J.U. type collection), from Loc. 64 (L.S.J.U.), pebbly sandstone near Comondú-Salada contact, Arroyo near La Palma, Lower California; Paratype: Left valve No. 56 (L.S.J.U. collection), B. F. Hake collector, Salada, Pliocene. Pecten beali appears to be related to P. carrizoensis Arnold, but is larger, and the ribs are more numerous and more deeply sulcate. On the left valve the radial interspaces are ornamented by small midribs which are lacking in Arnold's species. P. carrizoensis also is longer in proportion to the height than P. beali. This species is named in honor of Mr. C. H. Beal, whose information concerning Lower California has been much appreciated by the writer.» LEO GEORGE HERTLEIN, 1925
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