Elliptio tetrica (Lea, 1857)

1. Eaton Creek, Marion Co., FL - 60 mm
2. St Marys River, Nassau Co., FL - 57 mm
3. North Fork Black Creek, Clay Co., FL - 48 mm
4. Hurrah Creek, Hillsborough Co., FL - 55 mm
5. New River, Bradford/Union Co., FL - 60 mm
6. St Marys River, Charleton Co., GA - 64 mm

Type locality: Flint River, near Albany, Georgia.

Range: Apalachicola, St Johns, St Marks, St Marys, Suwannee, Withlacoochee, Wekiva, Alafia, Chipola and Ochlockonee River systems.

Remarks: This species is often found in association with Elliptio icterina. That species typically is rayed and pointed posteriorly. Elliptio tetrica is rayless, even as a juvenile, and broadly rounded or square posteriorly. The periostracum of old individuals of tetrica becomes shaggy and loses the shiny luster of young ones -- in icterina, most individuals are shiny throughout their life.

Unio singularis Wright, 1899 is a synonym.

See remarks under oscari and occulta.