lateral line

dionea) confluent with caudal fin 1b) Second dorsal fin and anal fin 2 distinctly separate from caudal fin 2a) Vomerine teeth present; pelvic fin Palatogobius narrow, lacking a well-developed frenum; preopercular canal pores absent 2b) Vomerine teeth absent; pelvic fin 3 rounded or oval, with a well-developed frenum; preopercular canal pores present or absent 3a) Top of head naked; second dorsal Microgobius typically I,14-17 3b) Top of head scaled; second dorsal 4 typically 1,11-13, rarely 1,14 4a) Preopercular canal pores absent, head Parrella (P.

Cave-adapted sculpin from Perry County, Missouri, have smaller eyes (1-6% SL), fewer pelvic fin rays (3 + 3 or 3 + 4), enlarged cephalic canal pores, and reduced pigmentation (Burr et al., 2001).