Dobsonflies and Fishflies (Megaloptera) are a very small group of aquatic insects. The best known in the group are the hellgramites (Dobsonfly larvae) which are collected as a favorite bait for fishing. The adults of this group are secretive and seldom seen.
There are only 2 families of Megaloptera in Ohio, Sialidae, the alderflies or fishflies, and Corydalidae, the Dobsonflies. Among the Sialidae there is just one genus, Sialis. Among the Corydalidae, there are 3 genera, Chauliodes, Corydalus and Nigronia.