Fish of DuPage: Fish of Lake Michigan, Fish Anatomy, Other sketches.
Cyprinidae (Minnow)
Semotilus atromaculatus Creek Chub: Dark spot at anterior base of dorsal fin. Dorsal fin origin usually behind pelvic fin base. Rounded snout; large, terminal mouth. Pale olive and silver sides. Dark stripe on side of body. Pale-colored fins. Often used as bait.
Cyprinidae
Campostoma anomalum Central Stoneroller: Forked caudal fin. Long snout overhangs inferior mouth. Hard ridge on lower jaw. Tubercles present on male on head and olive-colored body. Prefers riffle areas with gravel bottoms, bottom feeder.
Cyprinidae
Etheostoma nigrum Johnny Darter: Large pectoral fins. High dorsal fins. Eyes almost on top of head. Rounded tail fin. Blunt nose and terminal mouth. Dark, XW-shaped blotches on side of body. Dorsal and tail fins clear with dark speckles. Gold-green iridescence.
Cyprinidae
Nocomis biguttatus Hornyhead Chub : Crimson eye spot. Tail red in young. Male breeding tubercles on top of head extend beyond the eye. Distinguished from Creek Chub by: barbel at posterior end of jaw, complete lateral line of 38-48 large scales (49-64 in Creek Chub), anal fin of 7 rays (8 in Creek Chub)
Cyprinidae
Rhinichthys atratulus Blacknose Dace: Elongate, stocky body. Forked tail fin. Inferior mouth; long snout, overhangs the mouth. Tubercles small and present on male on head, body, and all fins. Somewhat long anal fin. Dark olive-colored body, dark side stripe. Speckled back. Lower side may have orange color.
Cyprinidae
Phoxinus erythrogaster Southern Redbelly Dace: Scarlet belly, yellow fins with metallic silver surrounding base of pelvic and pectoral fins. 2 dusky stripes along side separated by broad light stripe. Tiny scales, almost invisible. Lives in schools, often in association with stonerollers and creek chubs.
Cyprinidae
Luxilus cornutus Common Shiner: Common bait fish, hybridize with other minnows. Dorsal fin origin above front half of pelvic fin base. Rounded snout with terminal mouth, large eye. Dark crescents on side of body. Top of body olive, silver sides and belly. Dorsal, tail, pelvic, and anal fins have red band with pale outer margin. Breeding males have rose-colored bellies.
Cyprinidae
Cyprinus carpio Common Carp: Native to Eurasia, has habit of stirring up the bottom while feeding, causing siltation and turbidity. Heavy and strongly serrate spines in the anterior portion of its dorsal and anal fins, 2 fleshy barbels on each side of its upper jaw.
Ictaluridae (Catfish)
Ameiurus melas Black Bullhead: Robust scaleless body, compressed posteriorly. 8 elongated fleshy barbels. Chin barbels dark. Sharp dorsal and pectoral spines. Depressed head, slightly inferior mouth. Tail fin not forked. Rounded anal fin. Grayish body, mottled coloring on the body. Fins brown or black.
Centrarchidae (Sunfish)
Lepomis macrochirus Bluegill: 2 dorsal fins with spinous and soft-rayed portions united, small mouth, long pointed pectoral fins, faint black spot on soft-rayed part of dorsal fin/ Solid black gill-tab of the adult and dark bands that extend the full depth of its body.
Centrarchidae
Ambloplites rupestris Rock Bass: 2 dorsal fins with spinous and soft-rayed portions united. Compressed, stocky body, olive-brown peppering. Large, terminal mouth, red eye. Rounded pectoral fin. Dark-edged anal fin. Almost straight-edged tail fin. 6 anal spines.
Centrarchidae
Micropterus salmoides Largemouth Bass: Dark, olive-colored side often striped and blotched. Large, terminal mouth. Deep notch between 1st and 2nd dorsal fin. Tail fin slightly forked. End of jaw may extend past the eye. Black opercular spot. 3 horizontal, dark green bars on cheek. Olive-brown mottling on fins, olive stripes and blotches.