Late Pliocene to Early Pleistocene; Extinct.
Original Description (from Mansfield, 1939, p. 56):
"Shell solid, robust, obliquely oblong, of moderate size, equivalve and inequilateral. Beaks full, high and strongly prosogyrate. Ribs on right valve of cotype 17 in number, strong, elevated, weakly undercut, a little wider than the interspaces and strongly transversely nodulated; the fourth rib counting from the dorsal margin on the posterior side is weaker than the others and lies close to the posterior one. Left valve of cotype immature, ornamented with 18 ribs; the third and fourth, counting from the dorsal margin, are closely spaced, and the rib in front of it is a little weaker than the others; the other ribs over the disk are of the same strength.
Dimensions of cotypes (U.S. Nat. Mus. no. 497976) -- Right valve, length 43 millimeters; height, 39 millimeters; diameter 24 millimeters; left valve, posterior margin broken away; height, 28 millimeters; diameter, 15 millimeters.
Type locality. -- Station 14075, dredged from Caloosahatchee River, one mile below Olga, Florida.
Horison. -- Probably Pliocene.
Altogether six valves were collected, of which five indicate that they were taken from a sand and the other from an indurated limestone similar to that on another piece from this place having a Chione cancellata on it.
Venericardia olga n. sp. is related both to Venericardia hadra Dall, a species from the Chipola formation, and V. himerta Dall, a species from the Oak Grove sand, but differs from both of these species in having wider and stronger ribs, especially over the earlier part of the shell. The new species somewhat resembles a varietal form of V. laticostata Sowerby, a living species from Panama, but the posterior side is less truncate and the ribs are higher than those of the varietal form of laticostata."
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