The family Corydalidae contains the megalopterous insects known as dobsonflies and fishflies. Making up about one dozen genera, they occur primarily throughout the Northern Hemisphere, both temperate and tropical, and South America.

They are sizeable Megaloptera, with a body usually larger than 25 mm (1 inch). They often have long filamentous antennae, though in male fishflies they are characteristically feathered. Ocelli are present; the fourth tarsal segment is cylinder-shaped. The four large wings are translucent, smoky grey, or mixed, and the anterior pair is slightly longer than the posterior one.