Thanks, David. Here are some references that might help in identifying
species of Chesapecten:

Ward, Lauck W., 1992, Molluscan biostratigraphy of the Miocene, Middle
Atlantic Coastal Plain of North America: Martinsville, Virginia Museum of
Natural History, Memoir no. 2, 159 pp., 26 pl. (Chesapecten: p. 68-73, pl.
2, 57, 11, 14-16, 18, 20.)

Ward, L. W., and Blackwelder, B. W., 1975, Chesapecten, a new genus of
Pectinidae (Mollusca: Bivalvia) from the Miocene and Pliocene of eastern
North America: U.S. Geological Survey, Professional Paper 861, 24 pp.

____1987, Upper Pliocene and lower Pleistocene mollusks of the Lee Creek
Mine, Aurora, North Carolina. In Ray, C. E., ed., Geology and paleontology
of the Lee Creek Mine, North Carolina, II. Smithsonian Contributions to
Paleobiology, no. 61, p. 113-283, 47 pl.

Although Ward claimed in his 1992 paper to have named a new subgenus
Chesapecten within the preexisting genus Chesapecten Ward & Blackwelder,
1975 (p. 68), this was an error. Whenever a genus is named for the first
time, a 'virtual' subgenus of the same name is considered to have been
automatically erected, whether it is ever used or not, so the subgenus
Chesapecten must be credited to Ward & Blackwelder, 1975.

Be that as it may, this is a good moment to reflect on the peculiar and
amusing method of naming genera by eliding two words together. Chesapecten
derives from Chesapeake [Bay] and Pecten, and these fossil scallops are
indeed common in the cliffs along the western shore.

Andrew K. Rindsberg
Geological Survey of Alabama