Common name(s): scorpionflies, hangflies
Description: Medium in size, Hypognathous mouthparts with an elongate rostrum formed from slender, serrate mandibles and maxillae and elongate labium. Fore and hind wings are narrow and have similar shape and venation. Legs are raptorial. They have large separated compound eyes and filiform multisegmented antennae. The abdomen has 11 segments, with the first two fused to the metathorax. The cerci have one or two segments.
Immature stages (larvae) are mostly terrestrial, with a heavily sclerotized head capsule, compound eyes, short and joined thoriasic legs, and the abdomen usually has prolegs.
Mecoptera is an order with about 500 known species, in nine families, with common names associated with the two largest families: the Bittacidae (hangflies) and Panorpidae (scorpionflies). In the Permian fossil beds of Elmo, Kansas they accounted for 40% of known fossils (considering that Mecoptera, like all insects, have exoskeletons made of chitin, not bone, which fossilizes less readily, that is a lot of fossils).
Development is holometabolous.
The dietary habits of mecopterans vary among familes and often between adults and larvae. Hangflies are predatory as adults, but as larvae are saprophagous. Scorpionflies are saprophagous, probably on dead arthropods, as both adults and larvae. Less is known about the eating habits of other families, but saprophagy and phytophagy (including the eating of moss) have been observed.
Copulation in some mecopterans is preceded by elaborate courtship rituals that can involve nuptial feeding. Larval development most often occurs in moist litter (or aquatically, such as the Gondwanan Nannochoristdae).
Some adult Mecoptera resemble neuropterans, but appear to be related to the Diptera (and therefore, possibly, the Strepsiptera).
sourced, in part, by The Insects: An outline of entomology, second ed. Gullan, P.J. and P.S. Cranston. Blackwell Science, Great Britain, 2000.
Parasitic Insects. Askew, R. R. Heinmann Educational Books, London, 1971.