Dobsonflies

Dobsonfly
Protohermes grandis
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Megaloptera
Family:	Corydalidae
Subfamily:	Corydalinae
Genera
9, see text

9, see text

Dobsonflies are a subfamily of insects, Corydalinae, part of the Megalopteran family Corydalidae. The larvae (commonly called hellgrammites) are aquatic, living in streams, and the adults are often found along streams as well. The nine genera of dobsonflies are distributed throughout the Americas, Asia, and South Africa.

Adult dobsonflies are some of the largest non-Lepidopteran insects of temperate zones such as the United States and Canada, with a wingspan of up to 180 mm in some species of Corydalus. A species in China has been reported with a wingspan of 21 cm. The wings vary from a grayish to translucent shade, depending on the species, and the anal region of the hindwing is wide and folded at rest. Despite the large wings, adults are weak, fluttery fliers. The body is soft and reaches up to 75 mm in length, and coloration varies from yellow to dark shades of brown.

Male adults are easily recognized by their long, curving mandibles, reaching up to 40 mm in length, which they use in competition for females. It is possible that the mandibles may have been selected as secondary sex characteristics used by females to evaluate males during courtship. Males cannot use these mandibles to bite because they are too long; on the other hand, females have short, heavily sclerotized mandibles which enable them to deliver powerful bites when threatened. The antennae of males are also noticeably elongated, even longer than the mandibles.

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Wikipedia