Tracheliastes polycolpus is a species of copepod in the family Lernaeopodidae.

[2] The subspecies Tracheliastes polycolpus baicalensis has been described from Lake Baikal.

The female T. polycolpus prefer to attach themselves onto the anal and pelvic fins.

After attaching themselves onto the fish, they feed on their epithelial cells and mucus on the host.

[2] Susceptibility to T. polycolpus depends on both host genotype and the environment.