North Carolina Wildlife Resources Commission

Eastern Creekshell (Conrad, 1834)

Scientific Name: Villosa delumbis

Classification:  State Endangered

Photo Credit: NCWRC
   

Interior

 

Exterior 

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

The eastern creekshell is very similar to the Carolina creekshell. The periostracum is yellow to dark golden brown with green rays. However, the rays of the eastern creekshell are usually broken instead of continuous. These rays may cover the entire shell or be restricted to the posterior slope. A dark layer of diatoms and algae may be obscure the true colors of the shell. This species also displays sexual dimorphism in shell shape with the posterio-ventral margin of the female becoming expanded with age, while the ventral margin of the male remains straight. The expansion demonstrated in eastern creekshell is usually more exaggerated than that seen in the Carolina creekshell. There are two pseudocardinal teeth in each valve; however, the posterior tooth in the left valve and the anterior tooth in the right valve may be vestigial. The lateral teeth are straight and well developed; two in the left valve and one in the right. Finally, the outer margins of the marsupium in the eastern creekshell are black; while, the outer margins of the marsupium in the Carolina creekshell are ivory colored.

 

Shell Anatomy

 

This species ranges from the Altamaha River Basin, Georgia, north to the Cape Fear River Basin. Distribution by County: Catawba River Basin: Burke Co. (Johns River) Union Co. (Waxhaw Creek, Six Mile Creek). Yadkin-PeeDee River Basin: Anson Co. (Brown Creek); Cabarrus Co. (Coldwater Creek); Montgomery Co. (Clarks Creek, Barnes Creek, Little River Subbasin, and Lake Tillery); Randolph Co. (Barnes Creek, Little River Subbasin); Stanly Co. (Bear Creek Subbasin); Union Co. (Goose Creek Subbasin, North Fork Crooked Creek, Richardson Creek, Rocky River). Cape Fear River Basin: Alamance Co. (Haw River Subbasin, including Stinking Quarter Creek, Mary's Creek, Back Creek, and Cane Creek); Bladen Co. (Cape Fear River); Brunswick Co. (Town Creek); Chatham Co. (Rocky River, Bear Creek); Cumberland Co. (Cape Fear River); Duplin Co. (Northeast Cape Fear River Subbasin); Harnett Co. (Cape Fear River); Moore Co. (Deep River); Orange Co. (Phils Creek); Pender Co. (Black River, Little Coharie Creek, Six Runs Creek); Rockingham Co. (Haw River). Waccamaw River Subbasin: Columbus Co. (Big Creek).

NOTE: All headwater areas that flow into these occupied habitats should receive special management.

 


R. I. Johnson (1970) described what he considered the species common habitat features as "mud or soft sand, particularly where rich in vegetable detritus, in small rivers and creeks."

This species is bradytictic. Little else is known of the life history of the eastern creekshell. 

General Life History For Mussels