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Chestnut Lamprey

Photo by Konrad Schmidt

Chestnut Lamprey

Ichthyomyzon castaneus

Federal Status: None

State Status: Threatened

Dark Blue = Designated critical habitat
Light Blue = Historical records

Comments: This fish is a long-term survivor with a bizarre life-cycle. Considered primitive because of its cartilaginous skeleton, 7-pored gill openings and lack of jaws, the chestnut lamprey has a larval stage and a parasitic adult stage. The adult will attach to a host fish using its disc-like sucking mouth. The host fish is most commonly a carp, sucker, gar, freshwater drum or catfish. After feeding on body fluids of the host fish, the lamprey releases itself and gathers to spawn in small, tributary streams. They collectively excavate a pit where eggs are deposited. The lampreys continue to excavate the gravel substrate upstream and thereby cover the eggs downstream. The young, sightless larvae drift to quiet backwaters with abundant organic material and burrow into the sediment. The larvae may remain several years before transforming to the adult stage. In the late 1800s, the chestnut lamprey was reported from the eastern third of Kansas. Today, the chestnut lamprey probably only exists in the Missouri River.