The Banded Killifish is a slender-bodied and laterally compressed topminnow. The snout is bluntly pointed, and the mouth is small, slanted and opens dorsally. It has a projecting lower jaw with very small teeth that are positioned in bands on both jaws. The dorsal fin is far posterior on the back, originating in advance of the anal fin, and has 10 to 13 rays. The anal fin has 9 to ll rays, pelvic fin 6 rays, and the caudal fin is rounded. A lateral line is absent, and there are 39 to 43 cycloid scales in the lateral series. The body is light olive on the back and sides and yellow-white below. There are usually 12 to 20 narrow vertical bars on the body. Adults average 2 inches or more in length.
The Banded Killifish has been collected from several natural lakes in Okoboji region of the Little Sioux River drainage (Dickinson County) and has been documented from the Missouri River. The Banded Killifish is not common anywhere in its range in Iowa. Its preferred habitat seems to be natural lakes that contain extensive amounts of aquatic vegetation.
Aquatic and terrestrial insects, planktonic crustacea, plant seeds, and fine algae material.
State Records are not documented for non-game species.
The Banded Killifish usually school in groups of few to many, cruising just below the surface of weedy lakes. The preferred habitat of the Banded Killifish seems to be shallow waters of glacial lakes and ponds that contain extensive amounts of aquatic vegetation. Over much of its range, the Banded Killifish also inhabits quiet backwaters at the mouth of streams and vegetated pools or sections of slow current in medium- to large-sized streams. It is well known to avoid the swift cold water of trout streams.
It feeds on a variety of items, such as aquatic and terrestrial insects, planktonic crustacea, plant seeds and fine algae material. Spawning occurs in late spring and early summer. The male courts, then selects a female. Eggs are released in clusters, fertilized and quickly develop a filament that adheres to the aquatic vegetation.
Recent stream sampling has not resulted in the discovery of any individual Banded Killifish, however, this species is more common in lakes and wetlands than streams. Complete stream sampling information is available from Iowa DNR's biological monitoring and assessment program.
Like the other topminnow species in Iowa, these fish have no importance to anglers. It is viewed as imperiled according to the Iowa Wildlife Action Plan, but it is not on Iowa's endangered, threatened, or special concern species list (571 IAC 77.2(2) (2015)).
Harlan, J.R., E.B. Speaker, and J. Mayhew. 1987. Iowa fish and fishing. Iowa Conservation Commission, Des Moines, Iowa. 323pp.
Iowa Department of Natural Resources, Iowa Wildlife Action Plan
Loan-Wilsey, A. K., C. L. Pierce, K. L. Kane, P. D. Brown and R. L. McNeely. 2005. The Iowa Aquatic Gap Analysis Project Final Report. Iowa Cooperative Fish and Wildlife Research Unit, Iowa State University, Ames.
Illustration by Maynard Reece, from Iowa Fish and Fishing.