The Firefly is a small, carnivorous beetle.

They are classified in the phylum Arthropoda, class Insecta, order Coleoptera, Lampyridae family of which there are about 1100 species.

Adult fireflies are elongate, relatively soft bodied beetles up to 2.5 cm (up to 1 in) long. The common North American species are about 1 cm (about 0.4 in) long. They are dark coloured but may have yellow or orange markings.

Both sexes usually fly, but in many species the females are wingless.

Males, females, and larvae emit a heatless luminescent, greenish-yellow to reddish-orange cool/cold light; in some species even the eggs glow.

Synchronised flashing is characteristic of some tropical species.

One very important reason that fireflies glow is to attract a mate.

Males and females of the same species will flash signals back and forth as a way of communicating. Each firefly species has its own particular pattern.

For example, the fireflies of one species will will fly around in the night sky and dive steeply just as the flash begins and turn upward to make a distinctive J shaped pattern of light. Female fireflies hang out on a tree branch or in the grass while the males fly around showing off their best flashes. When a female recognises the flash from a male of the same species, she will answer with her best flash.

Another reason that fireflies glow is to avoid predators. Fireflies are filled with a nasty tasting chemical called lucibufagens, and after a predator gets a mouthful they quickly learn to associate the firefly's glow with this bad taste! So not only does the flashing help attract a mate but it also warns predators to stay away.

A firefly flashes when oxygen, breathed in through the abdominal tracheae, is allowed to combine with a substance called luciferin under the catalytic effect of the enzyme luciferase. This reaction produces a very efficient light, with almost no energy lost as heat.

The timing of the firefly's flashes is controlled by the abundant nerves in the insect's light-making organ. The duration of the flashes depends on how long the luciferin takes to oxidise.

In the pyralis, a common North American firefly, for example, the male flies around and flashes about every five seconds. The female stays on the ground and flashes in response about two seconds later, thus providing the crucial cue to their union.

Fireflies are well represented in temperate regions, although the majority of species are tropical and subtropical.

They are nocturnal in their behaviour, and males commonly fly about in meadows on late spring and summer nights.

Adult fireflies are found in the same general habitats as their larvae.

The highest number of firefly species are found in warm, humid areas of the world around water such as ponds, streams, marshes or even depressions, ditches, etc., that may retain moisture longer then surrounding areas. Some species, however, are found in very arid regions of the world. In these arid regions, larvae and adults can be readily found following rains.

The greatest number of firefly species (highest species diversity) are found in tropical Asia and Central and South America.

Fireflies that glow are typically not found west of Kansas, USA, the reason for which is not known.

Most firefly larvae are found in rotting wood or other forest litter or on the edges of streams and ponds at night.

Some Asian species are fully aquatic (due to the presence of tracheal gills) and live underwater, feeding on aquatic snails. The larvae of several tropical firefly species in the genus Pyractomena are strictly arboreal, feed on arboreal snails and pupate while hanging under living leaves - similar to a butterfly chrysalis.

Pupation occurs after one or two years.

Most adult fireflies, however, eat only pollen and nectar or do not eat at all.

The larvae, which hatch from eggs laid on or in wet soil, feed on snails and earthworms, injecting their prey with a paralysing fluid.

Having lucibufagens is so important for survival that one species of firefly which can't make this chemical acquires it by eating other species that can make it. They do this by mimicking the flash pattern of another species and luring them in close. The unsuspecting male firefly thinks he is going to find a mate, but instead becomes a tasty treat to the tricky firefly. Talk about a bad date!

Firefly Larvae are predaceous and have been observed feeding mostly on earthworms, snails and slugs. Larvae can detect a snail or slug slime trail, and follow it to the prey. After locating their future meal, they inject an anaesthetic type substance through hollow ducts in the firefly's mandibles into their prey in order to immobilise and eventually digest it.

Multiple larvae have also been observed attacking large prey items, such as large earthworms. Other observations suggest larvae sometimes scavenge dead snails, worms and similar organic matter.

The common European glowworm is the female of the Lampyris noctiluca.

Asian glowworms are considered beneficial controllers of crop-damaging snails and slugs.

The members of one species of firefly in tropical Asia congregate in great numbers in trees and engage in synchronous flashing that begins with a single "pacemaker" insect. Waves of light travel up and down the tree or pass from tree to tree. Usually, only the males take part in this synchronous flashing.

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