Fessisentis

Fessisentis is a genus of parasitic spiny-headed (or thorny-headed) worms. It is the only genus in the family Fessisentidae. This genus contains six species that are distributed across the Eastern continental United States as far west as Oklahoma and Wisconsin. These worms parasitize salamanders and fish.

==Taxonomy and description== Species of Fessisentis are highly variable and there are few recognized diagnostic characteristics. Classification depends upon comparison of many characters, the ranges of which frequently overlap at the extremes however lemniscal length is a relatively consistent difference among species. == Species == There are six species in the genus Fessisentis. Fessisentis acutulus (Van Cleave, 1931)