Corydalus is a genus of large flying insects in the Corydalidae family, commonly known as dobsonflies. They are endemic to North, Central and South America and there are about 35 known species. Members of the genus have wing lengths of up to 85 millimetres. They are sexually dimorphic, with the males having large mandibles used to grasp the females during mating while the females have smaller jaws. The larvae are known as hellgrammites and are aquatic predators.