Blue Ridge Sculpin

The Blue Ridge sculpin (Cottus caeruleomentum) is a species of sculpin in the family Cottidae. It is native to the eastern United States, where it can be found in a number of river systems that drain into the Atlantic.

This fish is variable in morphology. It is up to about 6.3 centimetres (2.5 in) long. In general, the species has dark saddle marks and an incomplete lateral line. There are small spines on the preoperculum and small prickles in the postpectoral area. The breeding male, at least in some regions, has blue to blue-green coloration on the chin, the mouth, the bases of some of the fins, and the membrane connecting the bones around the gills. The fish is very similar to its close relative, Cottus bairdi, particularly the subspecies C. b. bairdi. The latter has notches in the band marking the base of the tail; C. caeruleomentum lacks the notches on one or both sides. C. bairdi lacks the blue breeding coloration; its chin is blackish. The two fish occur together and are known to hybridize.