Scientific Name: Cyclonaias tuberculata

Classification:  State Endangered

Photo Credit: NCWRC




NOTE: Hover over the bold words for definitions or see the Glossary.

Described by Rafinesque in 1820, the purple wartyback is appropriately named for its purple nacre and nodules mostly on the posterior half of the shell. The shell is thick, varying from somewhat circular to square in its general outline. There are two heavy pseudocardinal teeth in the left valve and one large tooth in the right valve. The lateral teeth are short and stout. A wing-like extension of the shell may extend above the posterior end of the hinge-line.


Shell Anatomy


The range of the purple wartyback includes the Upper Mississippi River Basin from Ontario south to Arkansas and the Cumberland and Tennessee river basins in Tennessee, North Carolina, and Virginia. In North Carolina, it is presently only know from the New River in Alleghany County, where it appears to be rapidly declining. NOTE: All headwater areas that flow into these occupied habitats should receive special management.The alewife floater ranges from Nova Scotia and New Brunswick, Canada, to the Potomac River in Virginia and Maryland (Johnson 1946, 1970, Burch 1975). A disjunct population is also known from the Chowan River in North Carolina (Shelley 1983). William Adams (pers. comm.) found live individuals in the Chowan River during the Summer of 1989. This species has also been documented from the Roanoke River below the last dam at Weldon down to Washington County.

Distribution by County: Chowan River Basin: Hertford Co. (Meherrin River, Chowan River); Gates Co. (Chowan River). Roanoke River Basin: Northampton Co. (Roanoke River); Washington Co. (Roanoke River). NOTE: All headwater areas that flow into these occupied habitats should receive special management.


This species is found in mixed substrates in waterways ranging in size from small streams to large rivers.

The purple wartyback is a tachytictic breeder with a reproductive period beginning in June and ending in August (Parmalee and Bogan 1998). Species in the catfish family, including the channel catfish, yellow bullhead (Hove et al. 1994, 1994a), flathead catfish, and black bullhead (Hove 1997) are effective fish hosts for this species.


General Life History For Mussels