Iowa DNR
BioNet
River & Stream Biological Monitoring
Fish and Benthic Macroinvertebrate Surveys
Physical Habitat Assessments

Slender Madtom Noturus exilis

Family
Ictaluridae (Catfishes)
Tolerance
Sensitive
Trophic Class
Benthic Invertivore
Is Exotic to Iowa?
False
Is Lithophilous Spawner?
False
Is Hybrid?
False
State Listing Status
Not Listed
Assessment Program Statistics

This species was found at 51 bioassessment sites, 4 rapid fish bioassessment sites, 2 fisheries assessment sites, and 0 fisheries presence-only assessment sites. In total, it was collected at 56 distinct sites, or 3.9% of the 1441 total sites monitored by the bioassessment program. It is the 65th most commonly collected species.

The Slender Madtom was collected in 128 bioassessment sampling sessions and 2 fisheries assessment sessions. It was present in 4 rapid bioassessment sessions and 0 presence-only sessions.

The biological assessment program has collected a total of 770 individual Slender Madtom specimens, ranking it the #66 most collected fish.

Species Characteristics

The body is yellowish on the sides and somewhat darker on the back. It has a white to cream-colored belly. The premaxillary band, or tooth patch on the upper jaw, is bar-shaped. The head is small, narrow and strongly depressed. There are 14 to 17 rays in the anal fin. No lateral stripe occurs along the side of the body. A light-colored, bar-shaped marking is on the back near the head and immediately above the dorsal fin. The upper jaw is somewhat longer than the lower. It can also be distinguished from other madtoms by the dark margin on the outer edges of the dorsal, anal and tail fins. It rarely exceeds 4- to 5-inches long.

Species Distribution Maps

HUC12 watersheds where this species has been found