Complex sentence: The sheepshead minnow, "Cyprinodon variegatus variegatus", is a subspecies of killifish, lives in salt marsh estuary environments, such as the Great South Bay estuaries of Long Island.
Split into simpler sentences: The sheepshead minnow ("Cyprinodon variegatus variegatus") is a subspecies of killifish found in salt marsh estuary environments. This includes the Great South Bay estuaries of Long Island.