FIREFLY

also called Lightning Bug, any of the nocturnal luminous insects of the beetle family Lampyridae (order Coleoptera), consisting of about 1,900 species that inhabit tropical and temperate regions. The common glowworm (Lampyris noctiluca) is a member of this family (see glowworm). Fireflies are soft-bodied beetles that range from 5 to 25 millimetres (up to 1 inch) in length, and have special light organs on the underside of the abdomen. The flattened, dark brown or black body is often marked with orange or yellow. Some adult fireflies do not eat; others feed on pollen and nectar. Both sexes usually are winged and luminous. Females lacking wings and resembling the long, flat larvae are commonly referred to as glowworms. The larvae, sometimes luminescent before they hatch, live on the ground and feed on snails and slugs. They inject a fluid into their prey and then withdraw the partly digested matter through hollow mouthparts. Most fireflies produce short, rhythmic flashes in a pattern characteristic of the species; the rhythmic flash is part of a signal system that brings the sexes together. Both the rate of flashing and the amount of time before the female's response to the male are important. Some authorities feel that the flashing is also a protective mechanism, reminding predators of the firefly's bitter taste. Some frogs, however, eat such large numbers of fireflies that they themselves glow. Firefly light is produced under nervous control within special cells (photocytes) richly supplied with air tubes (tracheae). Only light in the visible spectrum is emitted. Members of the coleopteran family Elateridae are also called fireflies (see click beetle).