Early Miocene to Late Pleistocene; Recent.
Southern Florida to Maryland.
For information on the modern distribution of the species, see Malacolog.
First English Description (from Conrad, 1837, p. 251-252):
"Shell cordate, inflated, thick and ponderous, with prominent, recurved concentric laminae, more elevated on the anterior and posterior margins; ligament margin arcuate; umbones prominent; lunule large, cordate, defined by a deep groove; posterior extremity slightly emarginate; cavity of the cartilage profound; teeth large, prominent, grooved; muscular impressions very large; inner margin regularly crenulated.
Inhabits Charleston harbor, South Carolina.
This large Venus occurs abundantly in the newer pliocene, on the plantation of Mr. Benners, in Craven County, North Carolina, and many specimens may be collected on the margin of the Neuse, where they have been cast by the waves. The only recent specimen I have seen, was obtained in Charleston harbor, and is now in the collection of the Academy of Natural Sciences. It is a much larger species than the Venus mercenaria, is proportionally shorter, and may be distinguished in every stage of growth by the prominent laminae covering the whole disk, which, when worn, presents a ribbed or sulcated surface. The largest I have seen is in possession of H. B. Croom, Esq., and measures about six inches in length.
It is named in compliment to Dr. S. G. Morton."
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