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Antlion, also spelled ant-lion and ant lion, is a name applied to a group of about 2,000 species of insects in the family Myrmeleontidae (sometimes misspelled as "Myrmeleonidae"). The best-known genus is ''Myrmeleon'' ("antlion"). Strictly speaking, the term "antlion" applies to the larval form of the members of this family, but while several languages have names for the adult, no word for them in English is widely used. Very rarely, the adults are called antlion lacewings. The length of a fully grown, well-nourished predatory larva is typically up to 1.2 cm, and that of an adult up to 4 cm.〔(Galveston County Master Gardeners: Beneficial insects in the garden )〕 The antlion larva is often called "doodlebug" in North America because of the odd winding, spiralling trails it leaves in the sand while looking for a good location to build its trap, as these trails look as if someone has doodled in the sand.〔(【引用サイトリンク】title=What are Antlions? )〕 ==Description and ecology== Antlions are worldwide in distribution, most commonly 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 lion". They can be fairly small to very large Neuroptera (wingspan range of 2–15 cm). The antlion larvae 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.〔Engel, Michael S. & Grimaldi, David A. (2007): The neuropterid fauna of Dominican and Mexican amber (Neuropterida, Megaloptera, Neuroptera). ''American Museum Novitates'' 3587: 1–58. (PDF fulltext )〕 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, multiveined 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. Antlions are easily distinguished from damselflies by their prominent, apically clubbed antennae which are about as long as head and thorax combined. Also, the pattern of wing venation differs, with the very long hypostigmatic cell (behind the fusion point of Sc and R1) being several times as long as wide. They also are very feeble fliers and are normally found fluttering 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. The lifecycle of the antlion begins with oviposition (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 larva is a ferocious-appearing creature with a robust, fusiform body, a very plump abdomen, the thorax bearing three pairs of walking legs. The prothorax forms a slender mobile "neck" for the large, square, flattened head, which bears an enormous pair of sickle-like jaws with several sharp, hollow projections. The jaws are formed by the maxillae and mandibles, which in each pincer enclose a canal for injecting venom between them. Depending on species and where it lives, the larvae either hide under leaves or pieces of wood, in cracks of rocks, or dig pits in sandy areas. Antlion larvae are unusual among the insects as they lack an anus. All the metabolic waste generated during the larval stage is stored and is eventually emitted as meconium near the end of its pupal stage.〔Piper, Ross (2007), ''Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals'', Greenwood Press.〕 The pupal stage of the antlion is quiescent. The larva makes a globular cocoon of sand stuck together with fine silk spun from a slender spinneret at the posterior 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 flies off in search of a mate. The adult is considerably larger than the larva; 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Antlion」の詳細全文を読む スポンサード リンク
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