WILDLIFE DISCOVERY : The Antlions

Antlions are a family of insects in the order Neuroptera with the scientific name Myrmeleontidae; the most well-known genus is Myrmeleo. There are about 2,000 species. Strictly speaking, the term “antlion” applies to the larval form of the members of this family.

Monday, May 03, 2010

Antlions are a family of insects in the order Neuroptera with the scientific name Myrmeleontidae; the most well-known genus is Myrmeleo. There are about 2,000 species. Strictly speaking, the term "antlion” applies to the larval form of the members of this family.

The antlion young one is often called "doodlebug” in North America because of the odd winding, spiraling trails it leaves in the sand while looking for a good location to build its trap, as these trails look like someone has doodled in the sand. It is also sometimes called sand dragon.

Antlions are worldwide in distribution, most common in arid and sandy habitats. A few species occur in cold-temperate places; a famous example is the European Euroleon nostras, whose scientific name means "our European [ant] lion”.

They can be fairly small to very large Neuroptera (wingspan range of 2-15 cm). The antlion eat small arthropods - mainly ants -, while the adults of some species eat small pollen and nectar, while others are predators of small arthropods in the adult stage too.

In certain species of Myrmeleontidae, such as Dendroleon pantheormis, the larva, although resembling that of Myrmeleon structurally, makes no pitfall, but seizes passing prey from any nook or crevice in which it shelters.

The adult has two pairs of long, narrow, multi-veined wings in which the apical veins enclose regular oblong spaces, and a long, slender abdomen.

Although they greatly resemble dragonflies or damselflies, they belong to an entirely different infraclass among the winged insects.

They also are very weak fliers and are normally found trembling about in the night, in search of a mate. The adult is thus rarely seen in the wild because it is typically active only in the evening.

They are highly active in desert regions and are a nuisance. They will deliver a small, mildly painful bite if given the chance to land on someone.

The life cycle of the antlion begins with egg-laying. The female antlion repeatedly taps the sand surface with the tip of her abdomen. She then inserts her abdomen into the sand and lays an egg.

The antlion young insect is a ferocious-appearing creature with a robust, fusiform body, a very plump abdomen, the thorax bearing three pairs of walking legs.

The pupal stage of the antlion is inactive. The young insect makes a globular cocoon of sand stuck together with fine silk spun from a slender spinneret at the later end of the body. These cocoons may be buried several centimeters deep in the sand.

It remains there for one month, until the completion of the transformation into the sexually mature insect, which then emerges from the case, leaving the pupal integument behind, 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.

The adult is considerably larger than the younger one; they exhibit the greatest disparity in size between larva and adult of any type of holometabolous insects, by virtue of the adults having an extremely thin, flimsy exoskeleton - in other words, they have extremely low mass per unit of volume.

Ends