Found only in Moss Spring and (historically) adjacent springs in the middle Tennessee River drainage in Alabama (Ref. 51664). The population from which this species was first collected in 1937 from Cave Spring near Smithsonia, Lauderdale County is now extirpated. The same is true for another population that was discovered in the Pryor Springs system in 1914 (Ref. 58011). Known to be extinct until its rediscovery in 1973 along margins of a spring-fed lake within Beaverdam Swamp, Limestone County, and in several areas of the drainage including Moss Spring, Beaverdam Creek, and Lowes' Ditch (Ref. 58014). Type locality: Moss Spring run into Beaverdam creek, 1.4 mi. north of Greenbriar, Tennessee R. drainage, Limestone Co., Alabama (Ref. 51664).

Status of threat: endangered; status declined since 1989. Criteria: 1,5 (http://fisc.er.usgs.gov/afs/) (Ref. 81264).