Any of about 100 species of small, slender freshwater fishes (family Percidae), native to eastern North America.
Darters live near the bottom of clear streams, darting quickly about when disturbed or when feeding on small aquatic animals such as insects and worms. They have two dorsal fins and often are brightly coloured. Most species are 2–3 in. (5–7 cm) long, but some grow to 9 in. (23 cm). Some species lay their eggs and abandon them; the males of other species establish a nest and guard the eggs until hatched. See also snail darter .