Natural history
Their native range is unusually focused: FishBase lists the Tangipahoa and upper Amite river systems in the Lake Pontchartrain drainage of Mississippi and Louisiana. A record elsewhere should therefore be checked against introduction history and identification.
Adults tend to remain near shoreline vegetation in pools and backwaters. This places them along sheltered edges rather than making them typical inhabitants of a fast river channel. The species is not an annual killifish, so it should not be assumed to follow the drought-surviving egg cycle associated with seasonal-pool killifishes.
Sources: Fundulus euryzonus species summary
