The slender chub (Erimystax cahni) is a species of ray-finned fish in the family Cyprinidae.

It is found only in the United States, within the Clinch and Powell rivers.

[5] Due in part to a lack of targeted surveys, slender chub have not been definitively observed since the 1990s.

The 2021 5-year review of this federally threatened species recommended environmental DNA sampling in future surveys with comparison to DNA extracted from preserved specimens.

[5] Environmental DNA surveillance was conducted in 2022, and eDNA for the species was detected in both the Clinch and Powell rivers.