The relict darter is known only from the Bayou du Chien drainage of western Kentucky. Page et first recognized this darter to be a distinct taxon and a member of the Etheostoma squamiceps complex of the sub-genus Catonotus. The relict darter is listed as federally endangered by the U. S. Fish and Wildlife Service (1993). Within the Bayou du Chien drainage, relict darters are known from only five sites. Of these, only one is known to be a site containing a reproducing population. The cause for the limited distribution of this rare darter is habitat degradation with poor land use practices as the primary culprit. Because this fishes’ entire known range consists of a single fragmented population, none of which is protected by public lands or conservation agreements, the possibility that a single event could result in the extinction of the species is a real concern. Maintenance of a captive population may be the only way to help insure that the species is not extirpated by such an event in the foreseeable future.
A small population has been housed at CFI since the original collection in 1999. Over the years there have been hundreds of these gems produced, but currently CFI houses only few individuals. Most of the offspring have been passed on to other hatcheries to help maintain their ark populations should conditions ever improve enough for them to be placed back into the wild.