Lightningbugs Putting on a Display

The flash of a lightningbug on a summers evening still inspires most of us to reach out and try to catch the enchanting light. Lightningbugs can be placed in a container for closer observation by children, but catch and release the same evening is the most kind. Adult lightningbugs do not live very long and have important things to accomplish – primarily to reproduce themselves.

Lightningbugs, also called fireflies, are actually a beetle. Lightningbugs are in a specific family of beetles called the Lampyridae. There are 124 species of fireflies in the U.S. and Canada, mostly in the East and South. Like all beetles, the fireflies have a complete life cycle consisting of four stages: egg, larva, pupa and adult.
Lightningbug larvae are usually found in moist areas such as under the loose bark of dead trees, under mulch and debris and within moist, loose soil. The worm–like larvae have six legs and in general appearance resemble ground beetle larvae. The underside of the lightningbug larva is round and creamy white. The top is brown and flattened with the segments expanded into shield–like plates that protrude slightly to the sides and to the back, overlapping the next segment. The full-grown length of the larvae is about 3/4 inch. The larvae possess light organs similar to those of the adults, and their luminescence often attracts the attention of gardeners. Lightningbug larvae are predacious and feed on small insects, snails and slugs.
Lightningbug larvae and adults produce light by an interesting reaction of chemicals and enzymes. The light produced is a "cold" light; that is, the chemical reaction produces nearly all light and very little heat. The light flashing is regulated according to a genetically fixed pattern and is used by the adults for courtship. It is one of the means by which the males and females recognize members of their own species. Each species has a distinctive pattern of flashes, varying in flash number, duration, interval between flashes, motion accomplished during the flash, height of the flash above ground and so forth. The males and females recognize their own species' flash and get together as a result of the illumination. Often females are resting in vegetation and it is the males in the air.
Females of some lightningbug species will mimic the flash of other species in order to lure in males and eat them. Adults of other species of lightningbugs feed on pollen and nectar. 


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