BLACKFIN DARTER
SCIENTIFIC NAME: Etheostoma nigripinne
Characteristics: The blackfin darter is distinguished from other members of the Etheostoma squamiceps species group by morphology of the soft dorsal fin on breeding males (Page et al., 1992). The fin is dusky gray or black to its margin and has three branches per ray. The second and third branches are of equal length and separated from the first. The branches have no knobs on their tips, but the fin rays have four or five rows of rectangular, clear to light yellow bars. The caudal fin has eight to 12 clear to yellow and black alternating bands. The spiny dorsal fin has a small knob on the tip of each spine, with a small black spot on each membrane anterior to each knob. Anal and pelvic fins are dusky with a narrow clear margin.
ADULT SIZE: 1.4 to 2.8 in (35 to 70 mm)
DISTRIBUTION: Etheostoma nigripinne commonly occurs in Highland Rim tributaries of the middle and lower Tennessee River drainage of Tennessee and Alabama upstream to the Flint and Paint Rock river systems. This species is noticeably absent from the Cypress and Shoal creek systems in Alabama and Tennessee, replaced there by E. corona andE. crossopterum, respectively. The blackfin darter does not occur sympatrically with any other species of the E. squamiceps species group found in Alabama, which includes the crown, fringed, andlollipop darters, E. corona, E. crossopterum, and E. neoperum, respectively (Page et al. 1992).
HABITAT AND BIOLOGY: Etheostoma nigripinne is the most common member of the E. squamiceps species group found in Alabama. Individuals usually inhabit areas characterized by a slow to moderate current over a slabrock substrate. They are infrequently found in other habitats, from spring runs to quiet areas on the margins of larger streams and small rivers. Spawning occurs from March through May, with males establishing territories under slabrocks as do other species of Catonotus. Spawning behavior is similar to E. corona and E. crossopterum. The diet of E. nigripinne has not been studied, but is speculated to be similar to other Catonotus. Page (1974b) examines the diet of E. spuamiceps and reports consumption of microcrustaceans, mayflies, midges, and lesser amounts of aquatic beetles, worms, and caddisflies.
ORGINAL DESCRIPTION: Braasch and Mayden described the blackfin darter in 1985.
ETYMOLOGY:
Etheostoma means strain mouth, possibly referring to the small mouth.
Nigripinne means blackfin, in reference to the dark fins of breeding males.
The copyrighted information above is from Fishes of Alabama and the Mobile Basin.
