Dirty Darter (Etheostoma olivaceum)

Description: 

The Dirty Darter is restricted to a small area in the Cumberland River Drainage in central Tennessee. They live primarily in pools and riffles with slab-rock and gravel substrate. Like other members of the subgenus Catonotus, this species spawns on the underside of flat rocks. In this group, males of some species have a golden edge on their second dorsal fin that is hypothesized to serve as an “egg-mimic” to attract females for spawning. As the common name suggests, breeding male Dirty Darters have a black coloration across their body.