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''Smilax'' sect. ''Nemexia'' is a section of plants in the family Smilacaceae. It consists of the herbaceous plants within the genus ''Smilax''. ''Smilax'' species fall into two groups with distinctive morphologies: one group has woody perennial stems with thorns and a vining habit, while the other group has herbaceous stems that die back to the ground each winter. ''S.'' sect. ''Nemexia'' is the taxon that comprises the herbaceous species. In the past it was often a genus of its own under the name ''Nemexia'' and taxonomists still need further study of the species of ''Smilax'' to determine its proper rank.〔http://www.bioone.org/perlserv/?request=get-document&issn=0007-196X&volume=056&issue=02&page=0166〕〔Fu, C., H. Kong, Y. Qiu, K. M. Cameron. 2005. (Molecular phylogeny of the East Asian-North American disjunct ''Smilax'' sect. ''Nemexia'' (Smilacaceae). ) ''International Journal of Plant Sciences'', 166(2): 301-309.〕 However the widely accepted taxonomic system of the ''Flora of North America'' does not recognize ''Nemexia'', nor does the (AP-site ). Thus ''Nemexia'' is not currently considered an accepted genus taxon by most plant taxonomists.〔(ISB: Atlas of Florida Vascular Plants )〕 The plants in ''Smilax'', are called carrion flowers for their malodorous flowers and those plants included in section ''Nemexia'' also have flowers that smell like rotten meat. The herbaceous species have greenish-yellow flowers and bloom in spring, they are fly pollinated. ==Phylogenetic relationships== |2= ''S. jamesii'' }} |2= }} |2= ''S. tsinchengshanensis'' }} |2= ''Heterosmilax japonica'' }} }} Cladistic analysis among several members of the section was carried out in 2005 on several gene sequences, including the plastid ''trnL-F'' and ''rpl16'' sequences and the nuclear internal transcribed spacer. The eastern North American species in the morphologically variable ''S. herbacea'' complex form a sister group to the western North American ''S. jamesii''. The analysis did not conclusively clarify whether the ''S. herbacea'' complex should be recognized as different species. The two East Asian species, ''S. riparia'' and ''S. nipponica'', formed two well-defined clades. It is hypothesized that the ancestor of this section evolved in Asia and spread to North America via the Bering Strait land bridge.〔 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「Smilax sect. Nemexia」の詳細全文を読む スポンサード リンク
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