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''Mastotermes darwiniensis'', common names giant northern termite and Darwin termite, is a termite species found only in northern Australia. It is a very peculiar insect, the most primitive termite alive.〔() Tree of Life Web Project. 2003. Isoptera. Termites. Version 1 January 2003 (temporary). http://tolweb.org/Isoptera/8212/2003.01.01 in The Tree of Life Web Project, http://tolweb.org/〕 As such, it shows uncanny similarities to certain cockroaches, the termites' closest relatives. These similarities include the anal lobe of the wing and the laying of eggs in bunches, rather than singly. It is the only living member of its genus ''Mastotermes'' and its family Mastotermitidae, though numerous fossil taxa are known. The termites were traditionally placed in the Exopterygota, but such an indiscriminate treatment makes that group a paraphyletic grade of basal neopterans. Thus, the cockroaches, termites and their relatives are nowadays placed in a clade called Dictyoptera. These singular termites appear at first glance like a cockroach's abdomen stuck to a termite's fore part. Their wings have the same form as those of the roaches, and its eggs are laid in a case as are roach eggs. It is thought to have evolved from the same ancestors as the wood roaches (''Cryptocercus'') in the Permian. Fossil wings have been discovered in the Permian of Kansas which have a close resemblance to wings of Mastotermes of the Mastotermitidae,〔http://tolweb.org/tree?group=Mastotermitidae Mastotermitidae picture〕 which is the most primitive living termite. This fossil is called ''Pycnoblattina''. It folded its wings in a convex pattern between segments 1a and 2a. Mastotermes is the only living insect that does the same.〔Tilyard RJ (1937) Kansas Permian insects. Part XX the cockroaches, or order Blattaria I, II Am. Journal of Science 34; 169–202, 249–276.〕 Unlike roaches, not all termites have wings: Only the reproductives (see Life cycle of termites), whose wings are considerably longer than their abdomen. ''Mastotermes darwiniensis'' is usually not very numerous, nor are the colonies large when left to natural conditions. However, when given abundant water (such as regular irrigation) and favourable food & soil conditions (such as stored timber or timber structures), populations can be enormous, numbering in the millions, quickly destroying their host. Its diet is varied, as it will eat introduced plants, damaged ivory and leather, and wood and debris, in fact almost anything organic. It becomes a major agricultural pest, to the extent that vegetable farming has been virtually abandoned in Northern Australia〔Hill, G.F., (1942) Termites (Isoptera) from the Australian Region. H.E. Daw, Govt. Printer, Melbourne, Austr.〕 wherever this termite is numerous, which it is outside of the rain forest or bauxite soils.〔Brittan EB et al. (30 authors) (1970) The Insects of Australia. Melbourne University Press. p. 285〕 It has developed the ability to bore up into a living tree and ring bark it such that it dies and becomes the center of a colony. ''Mastotermes darwiniensis'' is the only known host of the symbiotic protozoan ''Mixotricha paradoxa'', remarkable for its multiple bacterial symbionts. ==Fossil record== Numerous fossil taxa have been described in the Mastotermitidae, as well as in the genus ''Mastotermes''. The family seems to have had a worldwide distribution until just a few million years ago, when all but the ancestors of the giant northern termite became extinct for unknown reasons. Fossil genera included in Mastotermitidae are:〔Krishna, K., D.A. Grimaldi, V. Krishna, & M.S. Engel (2013) Treatise on the Isoptera of the world. ''Bulletin of the American Museum of Natural History'' 377: 1-2704.〕 * ''Blattotermes'' Riek (Eocene-Oligocene of France, USA, and Australia) * ''Garmitermes'' Engel, Grimaldi, & Krishna (Eocene of Europe) * ''Idanotermes'' Engel (Eocene of Europe) * ''Khanitermes'' Engel, Grimaldi, & Krishna (Early Cretaceous of Mongolia) * ''Miotermes'' Rosen (Miocene of Croatia, Germany, and France) * ''Spargotermes'' Emerson (Miocene-Pliocene of Brazil) * ''Valditermes'' Jarzembowski (Early Cretaceous of England) Fossil species of ''Mastotermes'' include:〔Krishna, K., D.A. Grimaldi, V. Krishna, & M.S. Engel (2013) Treatise on the Isoptera of the world. ''Bulletin of the American Museum of Natural History'' 377: 1-2704.〕 * ''Mastotermes anglicus'' Rosen, 1913 (Middle Oligocene of England) * ''Mastotermes bournemouthensis'' Rosen, 1913 (Late Eocene of England) * ''Mastotermes croaticus'' Rosen, 1913 (Early Miocene of Croatia) * ''Mastotermes electrodominicus'' Krishna & Grimaldi, 1991 (Early Miocene of the Dominican Republic) * ''Mastotermes electromexicus'' Krishna & Emerson, 1983 (Late Oligocene to Early Miocene Mexican amber) * ''Mastotermes gallica'' Nel, 1986 (Early Oligocene of France) * ''Mastotermes haidingeri'' (Heer, 1849) (Early Miocene of Croatia) * ''Mastotermes heerii'' (Göppert, 1855) (Late Oligocene of Poland) - tentatively placed in ''Mastotermes'' * ''Mastotermes krishnorum'' Wappler & Engel, 2006 (Middle Eocene of Germany) * ''Mastotermes minor'' Pongrácz, 1928 (Early Miocene of Croatia) * ''Mastotermes minutus'' Nel & Bourguet, 2006 (Eocene of France) * ''Mastotermes picardi'' Nel & Paicheler, 1993 (Late Oligocene of France) * ''Mastotermes sarthensis'' Schlüter, 1989 (Cretaceous of France) * ''Mastotermites stuttgartensis'' Armbruster, 1941 (Middle Miocene of Germany) - tentatively placed in ''Mastotermes'' 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「Mastotermes darwiniensis」の詳細全文を読む スポンサード リンク
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