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''Rafflesia'' is a genus of parasitic flowering plants. It contains approximately 28 species (including four incompletely characterized species as recognized by Willem Meijer in 1997), all found in southeastern Asia, in Indonesia, Malaysia, Thailand and the Philippines.〔(VJR Rafflesia Reserve, Forestry Department Sabah, Malaysia )〕 ''Rafflesia'' was found in the Indonesian rain forest by an Indonesian guide working for Dr. Joseph Arnold in 1818, and named after Sir Thomas Stamford Raffles, the leader of the expedition. It was discovered even earlier by Louis Deschamps in Java between 1791 and 1794, but his notes and illustrations, seized by the British in 1803, were not available to western science until 1861. The plant has no stems, leaves or true roots. It is a holoparasite of vines in the genus ''Tetrastigma'' (Vitaceae), spreading its absorptive organ, the haustorium, inside the tissue of the vine. The only part of the plant that can be seen outside the host vine is the five-petaled flower. In some species, such as ''Rafflesia arnoldii'', the flower may be over in diameter, and weigh up to . Even the smallest species, ''R. baletei'', has 12 cm diameter flowers. The flowers look and smell like rotting flesh, hence its local names which translate to "corpse flower" or "meat flower" (see below). The foul odor attracts insects such as flies, which transport pollen from male to female flowers. Most species have separate male and female flowers, but a few have hermaphroditic flowers. Little is known about seed dispersal. However, tree shrews and other forest mammals eat the fruits and disperse the seeds. ''Rafflesia'' is the official state flower of Indonesia, the Sabah state in Malaysia, and of the Surat Thani Province, Thailand. The name "corpse flower" applied to ''Rafflesia'' can be confusing because this common name also refers to the titan arum (''Amorphophallus titanum'') of the family Araceae. Moreover, because ''Amorphophallus'' has the world's largest unbranched inflorescence, it is sometimes mistakenly credited as having the world's largest flower. Both ''Rafflesia'' and ''Amorphophallus'' are flowering plants, but they are only distantly related. ''Rafflesia arnoldii'' has the largest ''single'' flower of any flowering plant, at least in terms of weight. ''A. titanum'' has the largest ''unbranched'' inflorescence, while the talipot palm (''Corypha umbraculifera'') forms the largest ''branched'' inflorescence, containing thousands of flowers; the talipot is monocarpic, meaning the individual plants die after flowering. ==Classification== ;Species *''Rafflesia arnoldii'' *''Rafflesia aurantia'' *''Rafflesia azlanii'' *''Rafflesia baletei'' *''Rafflesia bengkuluensis'' *''Rafflesia cantleyi'' *''Rafflesia gadutensis'' *''Rafflesia hasseltii'' *''Rafflesia keithii'' *''Rafflesia kerrii'' *''Rafflesia leonardi'' *''Rafflesia lobata'' *''Rafflesia manillana'' *''Rafflesia micropylora'' *''Rafflesia mira'' *''Rafflesia patma'' *''Rafflesia philippensis'' *''Rafflesia pricei'' *''Rafflesia rochussenii'' *''Rafflesia schadenbergiana'' *''Rafflesia speciosa'' *''Rafflesia tengku-adlinii'' *''Rafflesia tuan-mudae'' *''Rafflesia verrucosa'' ;Unverified species *''Rafflesia borneensis'' *''Rafflesia ciliata'' *''Rafflesia titan'' *''Rafflesia witkampii'' Comparison of mitochondrial DNA (mtDNA) sequences of ''Rafflesia'' with other angiosperm mtDNA indicated this parasite evolved from photosynthetic plants of the order Malpighiales. Another study from that same year confirmed this result using both mtDNA and nuclear DNA sequences, and showed the three other groups traditionally classified in Rafflesiaceae were unrelated. A more recent study found ''Rafflesia'' and its relatives to be embedded within the family Euphorbiaceae, which is surprising, as members of that family typically have very small flowers. According to their analysis, the rate of flower size evolution was more or less constant throughout the family except at the origin of Rafflesiaceae, where the flowers rapidly evolved to become much larger before reverting to the slower rate of change. 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「Rafflesia」の詳細全文を読む スポンサード リンク
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