Aug 12, 2005

Appendix - Firefly Facts

Fireflies are actually beetles!

Fireflies are not really "flies" but are beetles in the family Lampyridae (from the same Greek word which is the English source of the word lamp).

"Flies" have one pair of wings (like houseflies) while all other winged insects have two pairs of wings, or, four wings altogether. In general, when the common names of insects contain the word "fly" as part of a one word common name such as firefly, dragonfly or scorpionfly, the insects are not true flies and belong to another order of insects. When the word "fly" is hyphenated or follows the first word of an insect common name, it is most likely a true fly (and by definition, has only two wings.)

Habitat and Range
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.

Adult fireflies are found in the same general habitats as their larvae. Generally speaking, the highest number of firefly species are found in warm, humid areas of the world. The greatest number of firefly species (highest species diversity) are found in tropical Asia and Central and South America.

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 anesthetic 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.

Adult Fireflies also have mouthparts suggestive of predation (long sickle-shaped mandibles). Although it is widely known that fireflies of a few species mimic the mates of other species in order to attract and devour them, observations of adults feeding on other prey items are practically non-existent. It is likely however, that adults might feed on plant nectar in order to sustain their energy requirements in the adult stage (which can last several months or longer).

Baby, Light My Fire!
Mating occurs when the male lands by the female. The female lays her eggs at the base of plants on or in the moist soil. The eggs of some fireflies glow. The eggs hatch into firefly larvae which usually glow. These are called glow worms. The females of some fireflies are wingless and are also called glow worms. The larvae stage of the firefly may last one or two years, again depending upon the species.

When the larval stage is complete, the insect enters the pupae stage. It is now near the surface of the ground. This lasts about three weeks, and the pupae do not feed during this time.

Killer Queen

The adult finally emerges, and the cycle begins again. The adult usually feeds on nectar or nothing at all. Adults live only from one to three weeks. Some types of adult fireflies are predators. And some predatory females have learned a way to an easy meal. They have learned the flashing patterns of other species, known as aggressive mimicry. They flash a male of another species and when he lands to mate, she kills him and eats him!

The glow of the firefly is produced by a chemical reaction within their bodies. A chemical called luciferin produces the glow when an enzyme called luciferase is mixed with it. Oxygen is required for this reaction and is supplied by a special opening in the abdomen of the fireflies’ body. The lightning bug, as this little insect is sometimes called, controls the intensity of the flash by varying the amount of oxygen which is mixed with the luciferase.

Most light forms we are familiar with produce heat as a waste product of the light producing energy. The firefly has a very efficient means of producing light because no heat is produced by the light it emits. This effect, light produced without heat, is called luminescence, and if the light is produced by a living organism, such as lightning bugs, plankton at sea, or other creatures or plants, it is called bioluminescence.

Male Flashers Wanted!
Fireflies have been studied extensively by biologists, but we still don't know all there is to know about these fascinating insects. The flashing of the fireflies is thought by most scientists to aid in reproduction. Females, it is assumed, prefer males who can flash their light more frequently than others.

The timing and pattern of the flashing seems critical and varies by species. The light colours of the firefly can also vary by species and can be yellow, green, orange, or red. Some type of lightning bugs can produce two different colours of light.

The male typically flies over grassy fields flashing, the female lies in wait in the grass below. She will answer his flash with one of her own, signalling her willingness to mate.

Fireflies have developed a method to escape predation. Since the flash of light is pretty conspicuous, the male of some types have developed the strategy of turning sharply right or left immediately after the flash. Many critters, like dragonflies and frogs have developed a taste for fireflies. If you are around a pond or stream and notice a frog with a glowing throat you know he has been dining on fireflies!

The above is adapted from

More interesting info: Fireflies Offer Weapon Against Cancer - Spark Can Trigger Cancer Treatment Deep Inside the Body


pammy whammy said...

very informative... Thanks!! :D

nan said...

i like the part about the killer queens... another interesting nugget about fireflies - some species die after mating. those poor things..

fLoGgiE said...

Wow, did not know that there is so much to know about fireflies. I'll try some of them and share how they taste.