(Pyractomena borealis)

Fireflies, lightening bugs, glow bugs and I'm sure a few other names, tag this wondrous work of "Nature."

Many people associate the insect with their childhood memories and the simple, innocent pleasures of that time. You may even remember chasing the tiny glowing bugs on warm summer evenings and collecting them in a Mason jar with air holes punched in the top.

Maybe even, keeping the jar full in your bedroom over night before you let them go.

You may have been a curious child like myself and smeared a few on your arms to see if you would glow in the dark. You found out like I did that indeed, for a short period of time you did glow where the insect was smeared. Not as bright however, but it did glow.


Fireflies are also luminescent in the larvae stage, and during this period of life, they are sometimes called "glowworms."

You may observe this insect as it twinkles in the darkness and may wonder: "How do they make the light?"

Fireflies are not completely understood and the light making process is complicated. Their luminous glow is believed to come from their abdominal air tubes where a
chemical called luciferin is activated in a chemical reaction with the substance luciferase. A cold light is created by this chemical process.

Each species has its own rhythm. The flash is actually a "love call" that helps the insects find each other for mating. If you have chased this insect, you realize that you can disrupt the rhythm of the flashes. When I'm chasing a Firefly and I wave and miss, the beetle goes into stealth mode for several seconds. Unless you can see the beetle in flight, you will lose contact and that is what the beetle is counting on.

In other words, all energy is put into light, not heat from the light like incandescent light bulbs where only 10% of the energy goes to light and the rest of the energy goes into heat. The timing of the flash is believed to be due to the gas, nitric oxide, which controls delivery of oxygen to specialized light cells that use the oxygen to fuel chemical luminescence.

Firefly, Glow worm

Fireflies are found all over the world.

There are about 200 species of fireflies in the United States and Canada.

Photinus pyralis, is our most common species.

However, If you happen to live in the United States West of Kansas and Nebraska you are not likely to have these flashing insects in your area.

Although some isolated sightings of luminous insects have been reported from time to time throughout the regions of the Western United States. The reason for the regional distribution of this insect phenomenon is not known.

There are Fireflies in the west, but few glow and blink.

These insects, unfortunately, have disappeared in many areas even though they thrive in others. Once again, much has to do with the destruction of habitat, herbicides and insecticides. In some instances there is a cycle of plenty some years to less for a period of time. Most Lightening bug larvae are found in rotting wood or other forest litter or on the edges of streams and ponds at night.

You may also come across the larvae in a moist area of your gardens and can create a little habitat if you choose.

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 species in the genus Pyractomena are strictly arboreal, feed on arboreal snails and pupate while hanging under living leaves - similar to a butterfly chrysalis .

Adults are found in the same general habitats as their larvae and why not, they do breed and lay eggs there. Generally speaking, the highest number of species are found in warm, humid areas of the world. 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 species (highest species diversity) are found in tropical Asia and Central and South America.

Fireflies Mating

The Flash is for Several Reasons: to attract a mate, to warn other fireflies of danger and to convince predators that they're not tasty morsels. (Apparently the chemicals that make the light do taste bitter.) Although other insects can produce light, Fireflies are the only ones able to flash distinct signals.

For most of us, the Photinus pyralis, approximately 10 to 14 millimeters long--the males are larger than the females. They are dark brown with orange and yellow accents and have dull yellow margins around their wing covers.

At dusk, the warmest part of the night, the males cruise a few feet above the ground flashing for an hour or so, waiting for a female, sitting on vegetation below, to signal to Mr. Right. The chosen male moves in slowly, his light dims, they meet.

A few days later, the female lays a hundred eggs or so just under the soil and the adults die.

Now here is where it gets interesting.

Firefly Larvae and slug

After three or four more weeks, slightly luminescent larvae emerge to feed voraciously on soft-bodied insects, slugs, snails, grubs, and even worms, thus making good garden friends.

Notice the larvae attacking a slug in the picture to your right. In fall, they burrow underground for winter.

In late spring or early summer, after living one or two years in the soil, each larva builds a marble-sized mud protection around itself and changes into a pupa. And approximately ten days later, adult beetles emerge to eat pollen by daylight, twinkle by starlight and start the cycle over again.

Now here are some information you may not know about Fireflies.

Firefly Larvae

Firefly Larvae are predaceous and have been observed feeding mostly on earthworms, snails, slugs, and even some grubs. 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 immobilize 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.


Adults also have mouth parts suggestive of predation (long sickle-shaped mandibles).

Although it is widely known that 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).

By day, adults look like insignificant beetles (picture to your right). In fact, you and your kids probably wouldn't recognize one if you saw it resting on a nearby leaf. After all, they don't bite, carry disease or cause significant plant damage. But when the sun goes down, they fascinate just about everyone, their twinkles lighting up the night.

There have been several reports about sick and dead pet lizards, where the owners fed the reptile Lightening Bug beetles and larvae. This information lead scientists to the toxic nature of the beetles.

The toxins of the larvae remain in the adults killing off non native predators that lack immune systems or instincts to avoid the prey.


A Few Tidbits:

It is neither a fly, nor a bug. Rather, it is a beetle that belongs to Lampyridae family. It produces a cold light in its body, devoid of heat as well as any ultraviolet or infrared rays.

The light that emerges from its body has a wavelength ranging from 510 to 670 nanometers and is pale reddish, yellowish or green in color. Neither do they bite, nor do they have pincers.

They spend most of their lifespan as a larva. In the adult form, it survives for a very short span. Females lay their eggs in the soil and even the latter are reported to glow in the dark. After hatching, the larvae spend the summer eating tiny insects, larvae, and even slugs and snails. After a larva reaches adult stage, it usually stops feeding and survives on the nutrients built during the larva stage. Even when it does eat, it is mainly nectar or dew, for moisture.

The main aim of an adult Firefly is to find a mate and lay eggs before dying. Different species of fireflies have different communication system, based on the lighting patterns.

They produce light for three reasons - attracting mates, warning predators and telling other fireflies of danger. Male and female, both glow. However, their rhythmic flashing patterns depend upon the sex and the species. We see fantastic examples of synchrony in the natural world all around us.

Here is a part of history that goes back centuries.

There were persistent reports when the first Western travelers went to southeast Asia, back to the time of Sir Francis Drake in the 1500s, of spectacular scenes along riverbanks, where thousands upon thousands of Fireflies in the trees would all light up and go off simultaneously.

These kinds of reports kept coming back to the West, and were published in scientific journals, and people who hadn't seen it couldn't believe it. Scientists said that this is a case of human misperception, that we're seeing patterns that don't exist, or that it's an optical illusion. How could the Fireflies, which are not very intelligent creatures, manage to coordinate their flashing in such a spectacular and vast way?

It's easy..............

'Nature' continues to amaze us with wonders we can't explain.

Never second guess Creation or its Creator.

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