Indiana

The Circle of Life

Most certainly before, and almost 200 years since Thomas Say studied firefly species, scientists are still studying these unique, glowing creatures. While they are commonly referred to as flies, they're not flies at all. A firefly is a winged beetle that belongs to the family Lampyridae. Measuring from ¼" – 1¼" (five to 30mm) long, adult fireflies have dark, narrow, elongated bodies made up of three sections: head, thorax and abdomen. Fireflies are commonly marked with yellow, orange or pink streaks. The head consists of two large, compound eyes, a mouth with powerful mandibles and a set of antennae. The thorax is made up of six jointed legs and four wings. The stiff, outer wings, called elytra, cover and protect the softer, inner set of wings that are used during flight. While the inner wings flap powerfully during flight, the elytra remain open in order to give the firefly the lift it needs. Lastly, the abdomen is where the firefly's sexual organs are located and where females produce eggs. Fireflies, along with all other types of beetles, go through metamorphosis, which is a profound change in form from one stage to the next in the life of an organism. Throughout the life cycle of a firefly, four major stage transformations take place: egg, larva, pupa and adult.

The circle of life begins after male and female firefly mate, and the female lays up to (and some times more than) 100 tiny, round eggs in the soil. The soil must be moist and dark. After only a few weeks, the eggs hatch into little, brown glowworms. Just as a firefly is not an actual fly, a glowworm is not an actual worm; instead it is a larva. Larvae are immature fireflies in their second stage of life. Even though these unique glowworms are no larger than a period at the end of a sentence, they already have developed eyes, antennae, a mouth, mandibles, six legs and the small light organ on the underside of the abdomen. The larval stage is the longest stage of a firefly's life cycle, lasting anywhere from three months to three years. During this time, glowworms grow and expand so much that they actually outgrow their existing skin, causing the old skin to burst open and new, larger skin to grow back. This happens several times during the larval stage because glowworms spend their time eating as much as they possibly can in order to satisfy their ever-increasing appetite. A glowworm's one and only job is to eat, eat and then eat some more, and while they may not appear to be any kind of a predator, glowworms are skilled professionals when it comes to hunting prey. With enormous, unquenchable appetites, glowworms feast on snails, slugs, worms, mites and insect larvae, and do their hunting at night.


Once a glowworm fully matures, it no longer has the unstoppable urge to consume food, and moves on to a new mission, which is to pupate and become an adult firefly. With more than 170 identified firefly species found in the United States, and more than 2,000 species throughout the world, various species pupate various ways. For example, some glowworm species attach themselves to the bark of a tree by their backside and hang upside down to pupate, whereas other species use their bodies (including their mandibles and mouth) to burrow into the soil and build underground pockets in which they pupate. When the time is right, the glowworm's larval skin again, but for the last time, bursts open and reveals a soft, pale skin that quickly begins to harden and darken in the safety of the original case-like skin. While pupating is taking place, the pupa's eyes grow larger, its antennae get longer and wings form. Like all living creatures, the rate of maturity varies, and after what could be days, weeks or months, a fully grown adult firefly emerges from the pupal case. As an adult, the firefly will seek out a mate in order to reproduce and start the entire firefly circle of life all over again.