Late Pliocene to Late Pleistocene; Recent.
Southern Florida to North Carolina.
Original Description (from Conrad, 1866, p. 105):
"Description. — Orbicular-cordate; radiating ribs very spinous; spines very thick, tubular; interstices deep, rugoso-punctate; lunale broadly cordate; buccal side granulated.
Chama arcinella, Tuomey and Holmes (not Lamarck). Pliocene Fossils of South Carolina, p. 22, pi. vii.; fig. 4, 5, 6.
Observations. — This species differs from the recent one in being larger, much thicker, and more especially in having fewer spines, which are much thicker than in the recent species, and not in two series of thick and thin spines, which characterize the latter."
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