Orobitella floridana (Dall, 1899) has an apparently contradictory vernacular name, as the shell rarely reaches beyond 16 mm (about 0.6 inch) in length. But all is relative in nature: the species belongs to the family Lasaeidae, a group of clams noted for their very small size, with many members of the family reaching only about a couple of millimeters (about 0.08 inch). The Giant Montacutid has an oval, inflated, white shell with a sculpture of concentric lines that become stronger on the anterior (narrower) end. The species is not commonly found on the beaches of Southwest Florida.
![](https://static.wixstatic.com/media/f867c2_54150278edb84c1f9683bbf41564e6a9~mv2_d_1816_1569_s_2.jpg/v1/fill/w_147,h_127,al_c,q_80,usm_0.66_1.00_0.01,blur_2,enc_auto/f867c2_54150278edb84c1f9683bbf41564e6a9~mv2_d_1816_1569_s_2.jpg)
The Giant Montacutid, Orobitella floridana, from Sanibel. Photos by José H. Leal.