The Atlantic Semele, Semele proficua (Pulteney, 1799), is a close relative of the Purplish Semele, Semele purpurascens, a species presented in this column two weeks ago. The Atlantic Semele is a bivalve that may reach about 1.5 inches in size. Its shell is not as colorful as the Purplish Semele: it is usually ivory-white, internally yellow with reddish-brown or mauve speckles. The brownish ligament (the organic part that joins the shell valves and that keeps them slightly open when the animal is relaxed) is elongate, slanted.
The Atlantic Semele, Semele proficua, from Sanibel. Photo by José H. Leal.