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''Rhododendron'' subgenus ''Rhododendron'' is a subgenus of the genus ''Rhododendron''. With around 400 species, it is the largest of the eight subgenera (more recently reduced to five)〔 containing nearly half of all known species of ''Rhododendron'' and all of the lepidote (scales on the underside of the leaves) species.〔〔 == Taxonomy == The subgenus has traditionally included three sections: *''Rhododendron'' sect. ''Pogonanthum'' Aitch. & Hemsl, type ''Rhododendron anthopogon'' D.Don. Six species; Himalaya and adjacent mountains *''Rhododendron'' sect. ''Rhododendron'' L., type : ''Rhododendron ferrugineum'' L. 120 - 149 species in 25 subsections; temperate to subarctic Northern Hemisphere *''Rhododendron'' sect. ''Vireya'' (Blume) Copel.f., type ''Rhododendron javanicum'' (Blume) Benn. About 300 species in 7 subsections; tropical southeast Asia, Australasia. Has at times been considered as a separate ninth subgenus.〔 However, following phylogenetic analysis, Craven (2008) raised the appropriately named ''Pseudovireya'' subsection of ''Vireya'' to section rank, splitting it into two geographic ''clades'', the Asian mainland species as ''Pseudovirey''a, and the Malesian species as ''Discovireya'', making five sections in all.〔 The new sections are thus: *''Rhododendron'' sect. ''Discovireya'' (Sleumer) Argent, type ''Rhododendron retusum'' (Blume) Benn. 48 species, Malesia *''Rhododendron'' sect. ''Pseudodovireya'' (C.B.Clarke) Argent, type ''Rhododendron vaccinioides'' Hook.f. Ten species, Mainland Asia Characteristics: (Craven 2008) *''Discovireya'': Scales entire to undulate; corolla tubular-cylindric; stamens 10, exserted to included, staminal filaments glabrous or hairy from the base; capsule valves not twisting after dehiscence; seeds with a distinct tail at each end * ''Pogonanthum'': Scales incised; corolla salver-shaped; stamens 5–8, included, staminal filaments glabrous or hairy towards the base; capsule valves not twisting after dehiscence; seeds without distinct tails * ''Pseudovireya'': Scales entire; corolla campanulate; stamens 10, exserted, staminal filaments glabrous proximally and distally and hairy in the middle region; capsule valves not twisting after dehiscence; seeds with a distinct tail at each end * ''Rhododendron'': Scales entire to crenulate; corolla campanulate to funnel-shaped or tubular; stamens 10, exserted, staminal filaments hairy towards the base or glabrous; capsule valves not twisting after dehiscence; seeds without distinct tails * ''Vireya'': Scales sessile or sometimes stalked, lobed to deeply incised or sometimes entire; corolla campanulate, trumpet-like, salver-shaped, tubular or funnel-shaped; stamens (5–)10(–16), exserted to included, staminal filaments glabrous or hairy from the base; capsule valves twisting after dehiscence; seeds with a distinct tail at each end Craven also provides a formal Key to the subgenus. 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「Rhododendron subg. Rhododendron」の詳細全文を読む スポンサード リンク
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