Antlion

Antlions are a family of insects, classified as Myrmeleontidae, from the Greek "myrmex", meaning "ant", and "leon", meaning "lion". Antlions are small, fully developed larvae being 1.5 cm, and adults being 4 cm. Antlions are omnivorous. The antlion larvae eat ants and other insects, while the adult antlion eats pollen and nectar.

The antlion is most often called a "doodlebug". It gets this name due to the odd winding, spiralling trails it leaves in the sand while looking for a good location to build its trap. These trails look like someone has doodled in the sand and hence the name doodlebug.

The adult antlion has two pairs of long, narrow, multi-veined wings and a long, slender abdomen. Although they greatly resemble dragonflies or damselflies, they belong to an entirely different order of insects. Antlions are easily distinguished from damselflies by their longer, prominent, clubbed antennae and different type of wing pattern. They also are very feeble fliers and are normally found fluttering about in the night, in search of a mate. The adult is rarely seen in the wild because it is active only in the evening. During the day it rests, motionless, well-camouflaged by its transparent wings and brownish body.

The life cycle of the antlion begins with egg-laying or "oviposition". The female antlion repeatedly taps the sand surface with the tip of her abdomen. She then inserts the abdomen into the sand and lays an egg. The antlion larva is a ferocious-appearing creature with a robust, fusiform body bearing three pairs of walking legs and a slender neck. Its small head bears an enormous pair of sicklelike jaws (mandibles) with several sharp, hollow projections. Depending on species and where it lives, the larvae will either hide under leaves or pieces of wood, or dig pits in sandy areas.

The larva excavates a conical pit in the sand by crawling backwards in a spiral. As it is crawling it flips out sand grains with its jaws. With each pass it goes slightly deeper and begins making a slightly smaller circle. Thus as it slowly moves round and round, the pit gradually gets deeper and deeper. The crater can reach 2-4 centimeters across and almost as deep, with very steep walls. The larva waits quietly at the bottom of the pit with its body off to one side and concealed by the steep wall. Only its sicklelike jaws protrude from the sand and often they are in a wide-opened position on either side of the very tip of the cone.

When crawling insects, such as ants, fall into the pit they cannot get out as the sand grains on the sides of the cone keep slipping away. The falling sand grains also alert the larva to a potential meal. The larva will then generally flip sand in the direction of the falling grains causing small landslides which bring the victim down to the bottom of the pit where the larvae grabs it in its jaws. Antlion larvae are capable of capturing and killing a variety of insects, and can even subdue small spiders. The projections in the jaws of the insect are hollow and through this the larva will suck the fluids out of its victim. After consuming all the contents, the lifeless, dry carcass is flicked out of the pit, and the pit is readied once again.

Antlions are especially abundant in soft sand beneath trees or under overhanging rocks. Apparently the larvae prefer dry places that are protected from the rain. Eventually the larva attains its maximum size and undergoes metamorphosis. The entire length of time from egg-laying to adulthood may take two or three years due to the uncertainty and irregular nature of its food supply. When it first hatches, the tiny larva specializes in very small insects, but as it grows larger, it constructs larger pits and thus catches larger prey. When it is full-grown, the larva constructs a spherical cocoon of sand grains cemented together with silk. These cocoons may be buried several centimeters deep in the sand.

After a pupation period of one month, a tiny-winged imago emerges from the cocoon, leaving a small hatch at the opening, and climbs to the surface. After about 20 minutes the adult's wings are fully opened and it will fly off in search of a mate.

Fiction

In the computer game Half-Life 2, antlions are an alien threat and pest on Earth. They mostly live in sandy areas like beaches and live in underground colonies. They usually hide under the sand, waiting for anything unlucky to cross its path and then quickly surface and tear it apart.

Antlions are a constant and lethal pest for people living in areas near them, though both the Resistance and the Combine have different ways of dealing with them. The resistance uses pheropods, or "bugbait", containing Antlion pheromones to control and tame the Antlions. The Combine, however, use "thumpers" - large machines that repeatedly pound the ground and form "safe zones" that Antlions will not cross.

In addition to normal Antlions, there are also Antlion Guards. These are far larger and stronger versions of Antlions, and have the ability to issue orders to other Antlions. Bugbait has no effect on them, seeing as how Antlion Guards are the ones who originally possessed the pheromones bugbait contains.

In the game, Gordon Freeman fights these killer insects until he finds a Resistance base that offers him Bugbait. With the help of the bugbait, Gordon goads the Antlions into attacking the maximum security prison Nova Prospekt.