Dhondtichlamys johnsoni (W. B. Clark, 1895)
CLARK, W. B. 1895. Contributions to the Eocene fauna of the middle Atlantic slope. Johns Hopkins University Circular, 15 (121): 3-6. [p. 5]
1895 Pecten johnsoni W. B. Clark, 1895
Pecten johnsoni Clark; W. B. Clark, 1896, The Eocene deposits of the Middle Atlantic Slope in Delaware, Maryland and Virginia, plate 34, figures 3a, 3b.
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«Shell small, suborbicular, equilateral; surface with about 20 uniform distant, rounded eostae, and a few short eost.ae in interspaces near basal margin, the whole crossed by fine of growth. Dimensions: length, 14 mm.; height, 15 mm.
Loc. Potomac Creek, Va.» WILLIAM BULLOCK CLARK, 1895
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«Dhondtichlamys survived the end-Cretaceous mass extinction and is the earliest coarsely ribbed pectinid to be found in the Paleocene. The specimens that I have been able to examine directly belong to two possibly intergradational species, Dhondtichlamys johnsoni (Clark, 1895) and D. greggi (Harris, 1897), from the Upper Paleocene (Thanetian) and Lower Eocene (Ypresian) of the Gulf Coastal Plain of southeastern United States (see Palmer and Brann 1965, for stratigraphic and geographic data). These species resemble Cretaceous Dhondtichlamys in shell microstructure, shape, ribbing style, and microsculpture. Like some Cretaceous species, the lengths of the anterior and posterior auricles of the Paleocene forms are nearly equal, and the posterior margin of the posterior auricles is convex outward.»
WALLER, T. R. 2006. New Phylogenies of the Pectinidae (Mollusca: Bivalvia): reconciling Morphological and Molecular Approaches. In: S.E. Shumway & G.J. Parsons (Ed.), 2006: Scallops: Biology, Ecology and Aquaculture, 1-44, figs. 1.1-1.4. [p. 11]
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