Alderflies - Dobsonflies

Male Dobsonfly or Alderfly

Female Dobson or Alderfly

Insect Identification: 
The Dobsonfly, also known as "The King Bug" for its kingly features and intimidating tusks, is an insect of the subfamily Corydalinae, part of the megalopteran family Corydalidae. The most well-known species is Corydalus cornutus, the Eastern Dobsonfly. This is a long, dark-colored insect found in North and Central America. Their closest relatives are the fishflies. Though both male and female dobsonflies have sharp mandibles, those of an adult male dobsonfly are actually so big – up to 1 inch (25 mm) – that they are unable to harm humans This is also a good insect identification process, as they have such poor leverage that they are incapable of breaking the skin. Their mandibles are used exclusively during mating, where males show them off and grasp the females during copulation. Female dobsonflies, however, retain the short, powerful pincers they had as larvae, so they can inflict painful bites, which can draw blood. Not withstanding the males' inability to inflict harm, when threatened both sexes will raise their heads and spread their jaws menacingly. They are not poisonous, but possess an irritating, foul-smelling anal spray as a last-ditch defense.
Adults can generally be found from late spring into the middle of summer, preferring to remain near bodies of water, particularly the ones where they grew up. Once they emerge as adults they mate, deposit their eggs near the water (often on overhanging vegetation), then die. They are primarily nocturnal, and like most aquatic insects, are commonly attracted to bright lights.
Dobsonflies appear to be quite fearsome, having what appears to be tentacle-like appendages for mouth parts. In fact, the males of the species cannot even bite though females can deliver quite a painful bite if agitated. Males are also the only one of the species that have the identifiable long mandibles. Females have short mandibles. Dobsonflies can be spotted by these long mandibles that can be nearly half the length of their bodies. Their large wings cover most of their abdomen surface when viewed from the above. Dobsonflies begin life as aquatic larvae before graduating as an airborne insect. They are primarily nocturnal (night dwellers) and are naturally drawn to light sources at night. Larvae appear looking very much like centipedes early on while adults keep watch nearby.
Dobsonflies spend most of their life in the larval stage, during which they are called hellgrammites, and are familiar to anglers who like to use the large larvae as bait. Hellgrammites live under rocks at the bottoms of lakes, streams and rivers, and prey on other insect larvae with the short sharp pincers on their heads, with which they can also inflict painful bites on humans. The larvae reach to 2" to 3" in length, with gills all along the sides of their segmented bodies that allow them to breathe underwater. Their gills, primitive nervous systems, and hard, segmented bodies mean that once hooked, hellgrammites can survive for long periods wiggling underwater. In the Appalachians, children catch these for fishing bait as a test of courage, working their fingers into the mud under rocks until a hellgrammite bites, then grabbing the creature with the other hand and throwing it into a jar. A less painful way to catch them is to stretch a mesh net across a narrow point in the stream, forcing the net to the bottom, then have others upstream turn over rocks and disturb the creek bottom, forcing the hellgrammites into the streamflow so they are carried into the net, whence they can be plucked and put into bait buckets.

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ADULT SIZE (Length, not including legs):
50mm to 127mm (1.97in to 5.00in)


Fun Insect Facts:

After a few years of living and growing underwater, the larvae crawl out onto land and pupate. They stay in their cocoons over the winter and emerge only to mate. Upon emerging, they live for only seven days. While not generally believed to eat during their adult stage, some captive female specimens have been observed with their heads burrowed into blackberries.

Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Hexapoda
Class:	Insecta
Subclass:	Pterygota
Infraclass:	Neoptera
Superorder:	Endopterygota or Neuropterida
Order:	Megaloptera
Family:	Corydalidae
Subfamily:	Corydalinae

So where can these weird insects be found?

Alabama, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming.


Get out there and start some insect identification!