Killifish, or mud minnows, are a group of small fish that are under 7 inches in length. Unlike most fish, killifish can live in fresh and highly salty water but prefer grassy tidal areas in brackish water. They stalk the shallows of coastal rivers, marshes, and bays, feeding on small animals that live on the bottom. The Gulf killifish can reach up to 7 inches in length and displays sexual dimorphism, with males more colorful and patterned and females a plain tan to silver color.

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