Photographs of the different life stages of this large insect whose aquatic larvae are known as hellgrammites, its distribution, description, life cycle and biology.

Account from the Tree of Life of the Megaloptera (alderflies, dobsonflies, fishflies), formerly considered a suborder (Sialodea) of Neuroptera, generally considered to be among the most primitive of the holometabolous insect orders.

The characteristics of these insects, their life cycle, feeding and habitat, with illustrations.