views updated

Aeshnidae (dragonflies; class Odonata, suborder Anisoptera) A cosmopolitan family of large, swift-flying, hawker dragonflies which are usually strikingly marked with blue or green, although several genera are normally a uniform dark brown: Anax imperator (emperor dragonfly) is one of the largest dragonflies in Eurasia. Aeshnids have similar triangles in the fore and hind wings, a well-defined but small anal loop in the hind wings, the eyes broadly contiguous across the top of the head, the ocelli in a triangle around a raised tubercle, and the ovipositor complete and not projecting beyond the long anal appendages. The larvae have large eyes and elongate bodies. More than 430 extant species have been described.