Lampsilis cardium shell description:

“Shell large, rather solid, obovate, inflated, with very full, high beaks, which have a few coarse, irregular corrugations that are inclined to be doubly looped; surface generally nearly smooth, the rest periods well marked; epidermis normally shining, greenish, greenish-yellow or brownish with broad, bright green rays.  In old shells the rays are often nearly or quite wanting.  Hinge line usually incurved in front of the beaks and outcurved behind them; ligament large and prominent, extending under the beaks, and narrow in front of them.  There are two, somewhat compressed pseudocardinals in the left valve, one in front of the other, the hinder high and having a triangular outline, the front lower, and both of these are in front of the beak; the hinge plate is narrow and rounded behind them, and there are two rather short, slender laterals; right valve with two compressed pseudocardinals, the lower the higher, separated by a deep, nearly parallel-sided socket, and one high, curved lateral, which is sharply truncated behind; beak cavities deep and wide; muscle scars not deep, smooth, the hinder semicircular; nacre brilliant, silvery, bluish-white or sometimes a beautiful pink. In the female shell the marsupial swelling is pronounced, and the shell is generally higher than that of the male ”(Simpson, 2014; Mather, 2007).