Redfin Darter

Family: 
Percidae (perches) in the order Perciformes (perchlike fish)
Description: 

A moderately stout darter with about 12 indistinct dark crossbars on the back (crossbars often not evident). An enlarged black scale is present above the base of the pectoral fin; the cheek beneath the eye with a prominent dusky vertical bar; another bar extends forward from eye onto snout. Gill covers are broadly connected by a membrane across the throat. Belly scaled, but scales often small and inconspicuous. Lateral line usually ends beneath the soft dorsal.

Back mottled olive-brown, the crossbars (if present) dark brown. Sides light brown with scattered pale spots. Belly white with scattered dusky specks. Dorsal, tail and anal fins with faint brown bands.

Breeding males have scattered red spots on body; spinous and soft dorsal dusky with reddish spots at the base, followed by an orange-red stripe and a blue outer margin; tail fin similar in color to dorsal fins and with 2 orange-red spots at the base; anal fin mostly red with a blue margin; pelvic fins dusky blue.

Size: 
Adult length: about 1¾ to 2½ inches; maximum about 3 inches.
Habitat and conservation: 
In our state, redfin darters occur on gravel and shale riffles of small- to medium-sized prairie and Ozark border rivers. Other fish of this distinctive community include the western slim minnow, Neosho madtom and channel darter. Their preferred streams mark a unique transition zone from prairie lands to Ozark hills, and several human activities commonly degrade these waterways, endangering the fish.
Foods: 
Little is known of the redfin darter’s habits, but apparently they eat aquatic insects like many other darters.
Distribution in Missouri: 
Currently only occurs in the lower Spring River and its North Fork, in Jasper and Barton Counties (in southwestern Missouri). Formerly known from localities in Newton and Douglas counties.
Status: 
State Endangered; a Species of Conservation Concern in Missouri. Although populations also exist in nearby Kansas and Arkansas, the redfin darter is vulnerable to extirpation within our borders. To keep it from vanishing, we must protect its current and potential habitat by not damming its streams, by protecting against sedimentation and by preventing pollution and agricultural runoff from degrading the streams.
Life cycle: 
Little is known of the redfin darter’s breeding habits, although the species reproduces in April in Kansas.
Human connections: 
Darters have been called the “hummingbirds of the fish world” because of the brilliant and varied colors of the breeding males. The next time you admire the colorful fish at a pet store, remember that our own native species possess the same kind of beauty—and that some of them are endangered.
Ecosystem connections: 
As part of a distinctive community of fishes, the redfin darter represents a rare and important component of Missouri’s natural wealth.