Killifishes and Live-Bearers: Cyprinodontiformes

Killifishes and live-bearers vary greatly in length from about half an inch (1 centimeter) to nearly 13 inches (33 centimeters). Some of these fishes are sleek, and others are blunt at the ends and flat-topped. Males may be brightly colored, but most females are plain. The fins may have fancy extensions. There is no lateral (LAT-uhr-uhl) line system along the sides, but there is around the head. The lateral line is a series of pores and tiny tubes used for sensing vibrations and usually found along the sides of the body.