Fundulus zebrinus is a species of fish in the Fundulidae known by the common name plains killifish.

The fish is striped with the 12 to 28 dark vertical bars[4] that give the species its scientific name, meaning "like a zebra".

[4] This species feeds on chironomid larvae, copepods, nematodes, and other small animals.

[2] It may feed by scooping up and swallowing mouthfuls of riverbed substrate to obtain buried food objects.

[4] It is tolerant of brackish, alkaline, and salty water, more so than most other local fish species.

[3] The fish might perform this behavior as a stress response, and it might serve to protect it from sunlight and heat, predators, or low water levels, or to help rid itself of parasites.

[9] For a long time, fish of the closely related species Fundulus kansae were considered to be members of F. zebrinus, the names being synonyms.

Most introductions occurred when plains killifish were used as bait by anglers and escaped into the wild to establish new populations.