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:''This article is about the order Trypanosomatida, see also the genus Trypanosoma. Trypanosomatids are a group of kinetoplastid protozoa distinguished by having only a single flagellum. The name is derived from the Greek ''trypano'' (borer) and ''soma'' (body) because of the corkscrew-like motion of some trypanosomatid species. All members are exclusively parasitic, found primarily in insects. A few genera have life-cycles involving a secondary host, which may be a vertebrate, invertebrate or plant. These include several species that cause major diseases in humans. The three major human diseases caused by trypanosomatids are; African trypanosomiasis (Sleeping Sickness, caused by ''Trypanosoma brucei'' and transmitted by Tsetse flies), South American trypanosomiasis (Chagas Disease, caused by ''Trypanosoma cruzi'' and transmitted by triatomine bugs), and leishmaniasis (a set of trypanosomal diseases caused by various species of ''Leishmania'' transmitted by sandflies). The family is known from fossils of the extinct genus ''Paleoleishmania'' preserved in Burmese amber dating to the Albian (100 mya) and Dominican amber from the Burdigalian (20-15 mya) of Hispaniola. The genus ''Trypanosoma'' is also represented in Dominican amber in the extinct species ''Trypanosoma antiquus''. ==Life cycle== Some trypanosomatids only occupy a single host, while many others are heteroxenous: they live in more than one host species over their life cycle. This heteroxenous life cycle typically includes the intestine of a bloodsucking insect and the blood and/or tissues of a vertebrate. Rarer hosts include other bloodsucking invertebrates, such as leeches, and other organisms such as plants. Different species go through a range of different morphologies at different stages of the life cycle, most have at least two different morphologies. Typically the promastigote and epimastigote forms are found in insect hosts, trypomastigote forms in the mammalian bloodstream and amastigotes in intracellular environments. 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「Trypanosomatid」の詳細全文を読む スポンサード リンク
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