The pirate perch (Aphredoderus sayanus) is a freshwater fish that commonly inhabits coastal waters along the east coast of the United States and the backwater areas of the Mississippi Valley.

In young individuals the anus is located between the pelvic fins, but migrates forward as the fish grows, before it settles on the throat region.

[7] Pirate perch may be the only known animal to exhibit a chemical camouflage, or crypsis that is generalized and effective among a wide number of potential prey species.

The pirate perch occurs in rivers of the Atlantic and Gulf slopes, the Mississippi Valley, and scattered parts of the eastern Great Lakes Basin.

[11]: 338  Its geographic range is very limited in the United States, and the creation of dams and the increasing effects of urbanization are restricting the overall habitat size for the fish, which could eventually lead to this species becoming extirpated in some areas.

[3] At first, the urogenital positioning of the pirate perch was speculated to serve to promote egg transfer to the fish's gill (branchial) chamber for gill-brooding.

[18] According to the Iowa Department of Natural Resources, some major threats that could affect their habitats could be siltation due to poor upland treatment.

Ohio has expressed some interest in conserving the species due to the perch having such a small area it can inhabit in the northwestern part of the state.