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''Kokia cookei'' is a small, deciduous tree commonly known as the kokio, Molokai treecotton, Cooke's kokio, or Molokai kokio. It is considered one of the rarest〔USFWS (1998): (''Recovery Plan for ''Kokia cookei ). U.S. Fish and Wildlife Service, Portland, OR.〕 and most endangered plant species in the world. Even when first found in the 1860s, only three trees could be located.〔USFWS. (''K. cookei'' Five-year Review. ) January 2008.〕 It was presumed extinct in the 1950s when the last surviving seedling perished. However, in 1970, a single plant was discovered on the same Kauluwai estate where the "last" individual grew, presumably a surviving relict of one of the plants previously cultivated there. Although this tree was destroyed in a fire in 1978, a branch that was removed earlier was grafted onto the related, and also endangered, ''Kokia kauaiensis''. Currently there exist about 23 grafted plants.〔 It is only known to have existed in the lowlands of western Molokai in the Hawaiian Islands. Presumably, its native habitat was lowland dry forests on the leeward western end of the island; this was all but cut down by Polynesian settlers about the year 1000 AD to make room for agriculture. It seems to have been noted by these settlers, as suggested by the native name ''hau heleula'' ("entirely red ''hau''").〔(''Kokia cookei'' ). Center for Plant Conservation (CPC) (2002). Retrieved 21 April 2011.〕 The three trees initially found grew near Mahana, northeast of Puu Nana〔 at approximately elevation.〔 Although the original forest ecosystem was destroyed and replaced by shrubland with plants like native ''iliee'' (''Plumbago zeylanica'') and introduced flora, Molokai kokio survived initially. It seems to have had some tolerance to habitat change, enabling it to hang on until the 19th century. ==Putative pollinators== Its eventual extinction in wild state of the species seems for a large part due to coextinction with native nectarivorous birds. ''K. cookei'' seems to be adapted to bird pollination like most related Malvaceae. The birds, Drepanidinae, were extirpated from dryland forest by Polynesians, and most remaining species entirely succumbed to mosquito-borne diseases like avian malaria (''Plasmodium relictum'') and fowlpox in the 19th century. The wide, large flowers of Molokai kokio would have admitted a wide range of potential pollinators (as opposed to e.g. ''Hibiscadelphus''): * Maui Nui alauahio, ''Paroreomyza montana'' ssp? – extirpated from island (prehistorically?) * Kākāwahie, ''Paroreomyza flammea'' – extirpated from lowlands by 1900, extinct (1963) * Common amakihi, ''Hemignathus virens'' – extirpated from lowlands by 1900 * Iiwi, ''Vestiaria coccinea'' – extirpated from lowlands by 1900 * Black mamo, ''Drepanis funerea'' – extinct (1907); not certain if it regularly occurred in habitat * Apapane, ''Himatione sanguinea'' – extirpated from lowlands by 1900 * Akohekohe, ''Palmeria dolei'' – extirpated from island (1907); not certain if it regularly occurred in habitat〔〔 Of these, the Iiwi was perhaps the most important, given that the other species are/were all either smallish and short-billed (''K. cookei'' has quite large flowers), or did probably not occur in its habitat in significant numbers. 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「Kokia cookei」の詳細全文を読む スポンサード リンク
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