The bluntnose darter may attain a length of slightly over two inches. Its cheeks are covered with scales. A black mark forms a semicircle from one eye to the other on the blunt snout. The back is green-brown with six dark saddles, and the sides are tan or light yellow. “X,” “V” or “W” marks are scattered on the sides and back. The sides also have horizontal dark blotches. There is a small, black spot at the base of the tail fin. A black “teardrop” mark is present under the eye. The lateral line is incomplete. The upper lip and snout are not connected by a flap of skin as in most darters. The breeding male has a black band in the middle of the first dorsal fin, a dark belly, dorsal and pelvic fins and projections (tubercles) on the pelvic and anal fins.
The bluntnose darter may be found in the southern three-fourths of Illinois. This fish lives in rivers, creeks, lakes, ponds and swamps. It is often found over a sand or mud bottom that has much dead, organic material. The bluntnose darter spawns in spring. Eggs are deposited on plants, algae or dead organic matter. It eats immature insects.