Snake flies are insects in the family Raphidiidae. Snakeflies, sometimes called camel-flies, are distinguished by their long necks. They are predators of small arthropods. Larvae live in leaf litter and eat aphids or other prey. Snakeflies have two pairs of membranous wings that are folded over the abdomen at rest. Females have a long tube at the end of the abdomen, an ovipositer, for laying eggs.
Snakeflies occasionally inhabit various areas of houses by accident, but mostly live outside on trees. Though seldom seen, these insects are common in wooded areas, usually in association with bark.
The larva, or immature stage, reaches ½ – ¾ inch in length when mature, and bears a flat, mottled, elongate, and soft body. When disturbed, larvae can move forward or backward quite rapidly.
Both larvae and adults feed mainly on other insects; thus, they are considered beneficial. Unlike house flies, snakeflies are not normally known to harm people or to damage houses or their contents. Some folks, however, have apparently received painful bites from the larvae.
Life Cycle: Snakeflies have a complete metamorphosis, with four stages in their life history: egg, larva,pupa, and adult. The egg stage lasts from a few days up to 3 weeks.
The larval period lasts at least one year, and in most species two or three years. The larvae of snakeflies are terrestrial. The larvae live under the bark of trees, or forestfloor or in the top layer of soil. Snakefly larvae are predators, caterpillars and the larvae of wood-boring. The larvae of a few species are found in rock crevices. The number of larval instars is not fixed, it varies around 10–11, but may reach 15 or even more.
The prepupal stage is always a short period of a 3-5 days duration only. Pupation takes place in spring and lasts from a few days up to 3 weeks. In very few species pupation takes place in summer and after a pupal stage of a 3-5 weeks, the adults hatch in late summer. All snakeflies need a period of low temperature 0°C.