Hatchetfish are small, oddly-shaped fish. These schooling fish live in freshwater streams in South and Central America. Many are raised in home aquariums. Some common hatchetfish include the Marbled Hatchetfish (Carnegiella strigata), the Silver Hatchetfish (Gasteropelecus sternicla), and the Winged Disc (Pterodiscus levis).
Anatomy: Hatchetfish have a very bowed ventral surface, giving this fish a distinctive shape. They have winglike pectoral fins which they can use to leap out of the water. Female hatchetfish are larger than males. Many hatchetfish have a tiny adipose fin located between the dorsal fin and the caudal fin (tail). Hatchetfish average about 2.5 inches (6 cm) long.
Diet: Hatchetfish are top-feeders who eat insects and their larvae.