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''Cupressus nootkatensis'' is a species of trees in the cypress family native to the coastal regions of northwestern North America. This species goes by many common names including: Nootka cypress, yellow cypress, Alaska cypress, Nootka cedar, yellow cedar, Alaska cedar, and Alaska yellow cedar. The specific epithet "nootkatensis" is derived from its discovery on the lands of a First Nation of Canada, those lands of the Nuu-chah-nulth people of Vancouver Island, British Columbia, who were formerly referred to as the Nootka. ==Taxonomy== First described in the genus ''Cupressus'' as ''Cupressus nootkatensis'' in 1824, it was transferred to ''Chamaecyparis'' in 1841 on the basis of its foliage being in flattened sprays, as in other ''Chamaecyparis'', but unlike most (though not all) other ''Cupressus'' species. However, this placement does not fit with the morphology and phenology of the cones, which are far more like ''Cupressus'', like them maturing in two years, not one. Genetic evidence, published by Gadek et al.,〔Gadek, P. A., Alpers, D. L., Heslewood, M. M., & Quinn, C. J. 2000. Relationships within Cupressaceae sensu lato: a combined morphological and molecular approach. ''American Journal of Botany'' 87: 1044–1057. (Abstract )〕 strongly supported its return to ''Cupressus'' and exclusion from ''Chamaecyparis''. More recently, Farjon ''et al.'' (2002) transferred it to a new genus ''Xanthocyparis'', together with the newly discovered Vietnamese golden cypress ''Xanthocyparis vietnamensis''; this species is remarkably similar to Nootka Cypress and the treatment has many arguments in its favour, as while they are not related to ''Chamaecyparis'', neither do they fit fully in ''Cupressus'' despite the many similarities. Little et al.,〔Little, D. P., Schwarzbach, A. E., Adams, R. P. & Hsieh, Chang-Fu. 2004. The circumscription and phylogenetic relationships of ''Callitropsis'' and the newly described genus ''Xanthocyparis'' (Cupressaceae). ''American Journal of Botany'' 91 (11): 1872–1881. (Abstract )〕〔Farjon, A., Hiep, N. T., Harder, D. K., Loc, P. K., & Averyanov, L. 2002. (A new genus and species in the Cupressaceae (Coniferales) from northern Vietnam, ''Xanthocyparis vietnamensis''. ) Novon 12: 179–189.〕 while confirming the above relationship with further evidence, pointed out that an earlier nomenclatural combination in the genus ''Callitropsis'' existed, as ''Callitropsis nootkatensis'' (D.Don) Oerst., published in 1864 but overlooked or ignored by other subsequent authors. Little et al.〔 therefore synonymised ''Xanthocyparis'' with ''Callitropsis'', the correct name for these species under the ICBN when treated in a distinct genus. The name ''Xanthocyparis'' has now been proposed for conservation, and the 2011 International Botanical Congress followed that recommendation.〔Mill, R. R. and Farjon, A. (2006). Proposal to conserve the name ''Xanthocyparis'' against ''Callitropsis'' Oerst. (Cupressaceeae). Taxon 55(1): 229-231.〕 In 2010, Mao et al. performed a more detailed molecular analysis and placed Nootka Cypress back in ''Cupressus''.〔Mao, K., Hao, G., Liu, J., Adams, R. P. & Milne, R. I. 2010: Diversification and biogeography of Juniperus (Cupressaceae): variable diversification rates and multiple intercontinental dispersals. - In ''New Phytologist''. 188(1):254-272.〕〔The Gymnosperm Database - (''Cupressus'' )〕 However, this is disputed, as the tree would compose a monophyletic subgenus. "The argument that it warrants treatment as a monotypic genus is not without merit, in which case the correct name is ''Callitropsis nootkatensis."''〔The Gymnosperm Database - (Cupressus nootkatensis )〕 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「Cupressus nootkatensis」の詳細全文を読む スポンサード リンク
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