Scorpionflies and Their Allies Order Mecoptera

Identification: Small to medium-sized. Body usually slender and relatively soft. Long-faced. Mouth parts chewing, at end of a long snoutlike structure. 4 membranous wings (wings rarely absent or vestigial); long and narrow, HW about same size as FW, with rather generalized venation but with extra cross veins; wings often spotted or transversely banded. Legs usually long, slender, the tarsi 5-segmented, with 1 or 2 claws. Antennae threadlike, about half body length. Metamorphosis complete.

Similar orders: (1) Neuroptera (p. 140): without a long-faced appearance; usually with numerous costal cross veins. (2) Dip-tera (p. 260): only 1 pair of wings. (3) Hymenoptera (p. 312): without a long-faced appearance; HW smaller than FW; wing venation different.

Immature stages: Eggs are generally laid on the ground, and larvae live in or on the surface of the ground or in moss. Larvae are usually caterpillarlike, with 8 pairs of short prolegs. They feed on dead insects and other organic materials.

Habits: Adults are usually found in areas of fairly dense vegetation; some are predaceous on other insects, others are omnivorous or are scavengers. The name "scorpionfly" is derived from the fact that the male genitalia of some species are large and conspicuous and carried curved upward over the back like the sting of a scorpion.

Importance: Scorpionflies are not of economic importance. They do not bite or sting.

Classification: Four families, separated chiefly by wing and leg characters.

SNOW SCORPIONFLIES Family Boreidae Identification: Dark-colored, 2-5 mm. Wings bristlelike or hooklike in <f, small and scalelike in 9 . 10th abdominal segment of 9 prolonged posteriorly into an ovipositorlike structure about half as long as abdomen (other 9 Mecoptera lack such a structure and have abdomen tapering posteriorly). Tarsi with 2 claws.

Snow scorpionflies occur in and feed on mosses. Adults appear in winter or early spring, and are usually seen on the snow (hence the common name). The bristlelike or hooklike wings of the male are used in grasping the female at the time of mating. In N. America there are 15 species, 2 in the East and 13 in the West (California to Alaska). They are not often collected.

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