''Rhododendron hirsutum'' ''Rhododendron'' subgenus ''Rhododendron'' is a

subgenus In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Rhododendron ''Rhododendron'' (; from Ancient Greek ''rhódon'' "rose" and ''déndron'' "tree") is a very large genus of about 1,024 species of woody plants in the heath family (Ericaceae). They can be either evergreen or deciduous. Most species are nati ...

''. 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 A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

(scales on the underside of the leaves) species.

Taxonomy

The subgenus has traditionally included three

sections Section, Sectioning or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sig ...

: *''Rhododendron'' sect. '' Pogonanthum'' Aitch. & Hemsl, type '' Rhododendron anthopogon'' D.Don. Six species; Himalaya and adjacent mountains *''Rhododendron'' sect. ''

'' L., type : ''

Rhododendron ferrugineum ''Rhododendron ferrugineum'', the alpenrose, snow-rose, or rusty-leaved alpenrose is an evergreen shrub that grows just above the tree line in the Alps, Pyrenees, Jura and northern Apennines, on acid soils. It is the type species for the genus ' ...

'' L. 120 - 149 species in 25 subsections; temperate to subarctic Northern Hemisphere *''Rhododendron'' sect. ''

Vireya ''Vireya'' rhododendron ''Rhododendron'' section ''Vireya'' (vireyas) is a tropical group of ''Rhododendron'' species, numbering about 300 in all. Vireyas are native to southeastern Asia and range from Thailand to Australia. Description ''Vir ...

'' (Blume) Copel.f., type ''

Rhododendron javanicum ''Rhododendron javanicum'' is a rhododendron species native to Indonesia, Malaysia, and the Philippines. This evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing seas ...

'' (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 ''Pseudovireya'', 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 ''Rhododendron'' (; from Ancient Greek ''rhódon'' "rose" and ''déndron'' "tree") is a very large genus of about 1,024 species of woody plants in the heath family (Ericaceae). They can be either evergreen or deciduous. Most species are nati ...

'' 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 Key or The Key may refer to: Common meanings * Key (cryptography), a piece of information that controls the operation of a cryptography algorithm * Key (lock), device used to control access to places or facilities restricted by a lock * Key (map ...

to the subgenus.

Subsections

** ''

References

Bibliography

Germplasm Resources Information Network: ''Rhododendron'' subgenus ''Rhododendron''
*Huxley, A., ed. (1992). ''New RHS Dictionary of Gardening''. Macmillan.
Gillian K. Brown, Lyn A. Craven, Frank Udovicic and Pauline Y. Ladiges. Phylogenetic relationships of Rhododendron section Vireya (Ericaceae) inferred from the ITS nrDNA region. Australian Systematic Botany 19, 329–342. August 2006. 10.1071/SB05019

External links

* Rhododendron Plant subgenera {{Ericaceae-stub