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Dobsonfly (Corydalus cornutus)

Detailing the identifying qualities of the Dobsonfly, including physical features and territorial reach.

 Updated: 8/18/2017; Authored By Staff Writer; Content ¬©

Picture of Dobsonfly

The large jaws and long mandibles on a male Dobsonfly may cry 'caution', but it's the fierce bite from a female that could hurt you.

Male 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 bite and are considered harmless to humans. The females, on the other hand,can deliver quite a painful bite from those strong jaws if she is agitated.

Male Dobsonflies can be identified by the long, fleshy mandibles that can be nearly half the length of their bodies. Females have much shorter ones. The large wings cover most of the abdomen surface when viewed from the above since they fold the wings over the body instead of splaying them out like butterflies might.

Dobsonflies begin life as aquatic larvae before graduating into an airborne insect. The larvae live underwater, feeding on tadpoles, small fish and other young aquatic larvae from other species (like dragonfly naiads and stonefly hellgrammites). Larvae look like underwater centipedes early in life, and adults keep watch over them from a nearby area above the water. Larvae can bite so handling them should be avoided though that does not stop anglers (fishermen and women) from using them as live bait.

Adults are primarily nocturnal (night dwellers) and are naturally drawn to light sources at night. They do not eat. Instead, they spend their days bringing forth the next generation of Dobsonflies.

Picture of the Dobsonfly
Picture of the Dobsonfly

Dobsonfly Information

Category: Alderfly or Dobsonfly
Common Name: Dobsonfly
Scientific Name: Corydalus cornutus

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Megaloptera
     Arrow graphic Family: Corydalidae
      Arrow graphic Genus: Corydalus
       Arrow graphic Species: cornutus

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 50 mm to 127 mm (1.95 inches to 4.953 inches)
Identifying Colors: black; brown; gray; white
Additional Descriptors: mouth, antennae, long, extra, flying, biting, jaws

North American Territorial Reach (Though Not Limited To): Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; 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; Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Nova Scotia; Ontario; Prince Edward Island; Quebec; Saskatchewan; Mexico

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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