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

American Brook Lamprey Lethenteron appendix

Petromyzontidae (Lampreys)
Trophic Class
Is Exotic to Iowa?
Is Lithophilous Spawner?
Is Hybrid?
State Listing Status
Assessment Program Statistics

This species was found at 43 bioassessment sites, 5 rapid fish bioassessment sites, 32 fisheries assessment sites, and 1 fisheries presence-only assessment site. In total, it was collected at 76 distinct sites, or 5.6% of the 1349 total sites monitored by the bioassessment program. It is the 55th most commonly collected species.

The American Brook Lamprey was collected in 92 bioassessment sampling sessions and 109 fisheries assessment sessions. It was present in 5 rapid bioassessment sessions and 1 presence-only session.

The biological assessment program has collected a total of 1,453 individual American Brook Lamprey specimens, ranking it the #57 most collected fish.

Species Characteristics

Olive-green to brown above, fading to light below. The dorsal fin is completely divided into two distinct fins. The mouth is a sucking disc, but is just wider than the body. Teeth are weak and are not formed in circular rows, but are in several groups or clusters. There are 65 to 70 myomeres between the last gill slit and the anus. Adults reach about 5- to 8-inches long.

Species Distribution Maps

HUC12 watersheds where this species has been found