
The Topeka shiner is a small minnow with an olive-yellow back, dark-edged scales, and silvery-white sides and belly. A dark stripe runs along the fish's sides and extends onto the head. All of the fins are plain except for the tail fin, which has a triangular black spot at its base. The anal fin has 6 to 8 rays, usually 7. There is a dark stripe on the back in front of the dorsal fin. The upper jaw does not extend beyond the front of the eye.
Breeding males have orange-red fins and orange-tinted heads and bodies. Numerous bumps are located on the snout, the top of the head, most of the body, and along the rays of some of the fins. The bumps are largest and most numerous around the head.
Total length: to 3 inches.

This species is not abundant at any location, but the largest concentrations occur in small streams in central Missouri.
Habitat and Conservation
Topeka shiners school in midwater or near the surface in runs and pools of small, moderately clear upland creeks with substrates of sand, gravel, rubble, and bedrock. Although the streams may cease to flow in summer, percolating groundwater or spring flow maintain some permanent pools. Conservation includes habitat restoration, animal containment areas, sustainable sand- and gravel-removal procedures, and urban sewer-system upgrades.
Food
Probably insects, although its food habits are not well documented.
Status
Endangered (state and federal). Both the Missouri Department of Conservation and the U.S. Fish and Wildlife Service have listed it as endangered.
Life Cycle
Topeka shiners spawn in silt-free gravel from late May to mid-July. They spawn over the nests of green and orange-spotted sunfish. Males are larger than females and defend small territories around the edge of sunfish nests. The maximum life span is three summers.
Human Connections
Minnows are more than "baitfish." Anyone who has owned an aquarium can attest to the intrinsic beauty of small fishes. Minnows also exhibit a diversity of interesting habits and adaptations, with unusual breeding colors (such as the orange-red fins of the breeding males) and nest-building behaviors.
Ecosystem Connections
We've all heard the old saw about the "big fish" eating the "little fish," but it's an ecological fact that small fishes, most famously the minnows, form a critical food source for all the animals that feed on them, and all the animals that feed on them.















