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.](https://static.wixstatic.com/media/7f077a_df91351ccb3e48d4af8add155ca51690~mv2_d_3000_2712_s_4_2.jpg/v1/fill/w_980,h_886,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/7f077a_df91351ccb3e48d4af8add155ca51690~mv2_d_3000_2712_s_4_2.jpg)
The Atlantic Semele, Semele proficua, from Sanibel. Photo by José H. Leal.