Southwest Florida Shells

by José H. Leal

Family Mactridae

Rangia cuneata

(G.B. Sowerby I, 1832)

Atlantic Rangia

Measuring up to 50 mm (about 2 inches), Rangia cuneata (also known as Gulf Wedge Clam) is a brackish water bivalve native to the Gulf of Mexico. The shell is heavy, whitish, and normally covered with a thick brown periostracum. As with most species of the family Mactridae, the ligament is internal. Capable of withstanding very low water salinities, the species has invaded estuaries of the East Coast of the US and northern Europe. The species is found locally in the Caloosahatchee estuary, where it thrives upstream almost to Lake Okeechobee. The shell in the main image was collected in 1958, by Dale Stingley, in La Belle, Hendry County, Florida. The additional image shows unpaired valves collected in 2019 by Lorin Buckner, under the Caloosahatchee River's Midpoint Bridge (between Fort Myers and Cape Coral.) All photos by Patricia Starkey.