(Federally listed as Threatened)
Description: The Neosho Madtom is a small catfish that rarely exceed three inches in length. Its coloration is a yellowish-tan background mottled with darker brown markings and four brown “saddles” along its back. Its head is relatively broad and flat, and it has a large dorsal (back) fin. It feeds on aquatic insects and invertebrates and is most active at night.
Habitat: The Neosho Madtom is found gravel-bottom riffles and runs in the Neosho River system. It spends most of its time on the bottom of the channel moving and hiding around stones and cobble.
Current and Historic Distribution: Currently, the Neosho Madtom can be found in Oklahoma only within a fourteen mile reach of the Neosho River near the Oklahoma/Kansas state line and well above Grand Lake. Most of the population occurs in the Neosho River in Kansas, and a small population may occur in the Spring River in Missouri. Historically, the Neosho Madtom was found throughout the Neosho, Spring and Illinois rivers in Kansas, Oklahoma, Missouri, and northwestern Arkansas.
Reasons for Decline: Reservoir construction appears to have had the greatest impact on the Neosho Madtom’s population. The construction of Grand, Hudson, Fort Gibson and Tenkiller reservoirs has permanently inundated most of the madtom’s historic habitat in Oklahoma and rendered it too deep to be suitable. Reservoir construction also has altered seasonal flow patterns and reduced the water temperatures below dams – especially below Lake Tenkiller.