Lollipop Darter (Etheostoma neopterum)

Description: 

The Lollipop Darter is restricted to a single stream system in the middle Tennessee River Drainage in south-central Tennessee and northern Alabama. 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 round structures on the rays of their second dorsal fin that are hypothesized to serve as an “egg-mimic” to attract females for spawning. As the common name suggests, these knobs on their second dorsal fin look like lollipops.