Rebeccapecten berryae Ward, 1992
WARD, L. W. 1992. Molluscan bioestratigraphy of the
Miocene, middle Atlantic Coastal Plain of North America. Memoirs of the
Virginia Museum of Natural History, 2: 1-159, pls. 1-26.[p. 64, pl. 24, fig. 1]
1992 Rebeccapecten berryae Ward, 1992
L. W. Ward, 1994, plate 24.
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«Pecten aff. P. trentensis Harris, 1919. Carter et a., 1988, Pl 7, fig. 50.
Diagnosis.— Disk moderately large, thick, with a variable number of large, very scaly ribs which radiate from a prominent beak. Description.— Disk somewhat higher than long, moderately large, thick, with a variable number of large, very scaly ribs, which radiate from a sharp, prominent beak. Ribs on the right valve, 10-12 in number, which tend to bifurcate with growth. Five ribs on the left valve, thin and pronounced with wide interspaces. Scales on the primary ribs wide and thin. Interspaces with numerous thin, scaly, radial striae. Right valve with moderately large byssal notch. Auricles with ffne scaly striae radiating from the beak. Umbones low, with the valve slightly arched. Arching interrupted at growth-resting stages to produce a somewhat nodose, undulant exterior. Interior of right valve capacious with a rounded ventral margin. Pallial line noticeable, but not impressed and marking the distal margin of thick shell material. Between the pallial line and shell margin the exterior ribbing is moderately reflected. Muscle scar large, posterior and sub-rounded. I-ength of holotype: 73.0 mm, height: 75.8 mm, convexity: 18.8 mm. Discussion.— This taxon is the probable descendant of Rebeccapecten trentensis (Hanis, 1919). It is different in that it is larger, heavier ribbed, and more convex. The primary ribs in R. berryae do not tend to bifurcate as they do in R. trentensis. The somewhat nodose appearance is only slight, and the taxon bears only some resemblance to Nodipecten. Etymology.— The species is named for Rebecca Berry, who worked for the U.S. Geological Survey in 1984-1985. Type information.— Holotype USNM 405194. Type locality: Silverdale Marl Company Quarry at Silverdale, 0.4 km SE of intersection of Rte. 1434 and Rte. 1442, Onslow County, N.C. (locality 30). Figured specimen.— Holotype (USNM 405194). Stratigraphic and geographic range.— Belgrade Formation, Haywood Landing Member (upper Oligocene and lower Miocene) in North Carolina.» LAUCK W. WARD, 1992
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