Rhododendron sect. Rhodora

Rhodora was a section of subgenus Pentanthera in the genus Rhododendron, that has since been discontinued.

Rhododendron sect. Rhodora
Rhododendron vaseyi
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Ericales
Family:	Ericaceae
Genus:	Rhododendron
Subgenus:	Rhododendron subg. Hymenanthes
Section:	Rhododendron sect. Rhodora (L.) G.Don 1834
Type species
Rhododendron canadense
Species
See text

Description

The section was closely related to sect. Pentanthera, differing from it in the flower corolla having only three lobes, rather than five, the upper three lobes of sect. Pentanthera being joined into a single three-lipped lobe in sect. Rhodora.

Taxonomy

The distinct floral structure resulted in Rhodora being treated as a distinct genus at one time. Treating it as such though resulted in the remainder of the genus Rhododendron being paraphyletic. However detailed phylogenetic analysis revealed that Rhodora was not a distinct entity, but rather polyphyletic, and it was disassembled, each species being allocated to other sections. Rhododendron canadense was moved to section Pentanethera, subgenus Hymenanthes and Rhododendron vaseyi was moved to section Sciadorhodion, which then became a new section of subgenus Azaleastrum.^[1]

It comprised two species, both deciduous shrubs native to eastern North America:

Image	Name	Distribution
	Rhododendron canadense (L.) Torr.	Canada in Newfoundland and extends into eastern Ontario and the United States from New York, New Jersey, and at high altitudes in the Appalachian Mountains further south to Pennsylvania.
	Rhododendron vaseyi A.Gray	North Carolina

References

1. Goetsch, Loretta A.; Eckert, Andrew J.; Hall, Benjamin D. (July–September 2005). "The molecular systematics of Rhododendron (Ericaceae): a phylogeny based upon RPB2 gene sequences". Systematic Botany. 30 (3): 616–626. doi:10.1600/0363644054782170. S2CID 51949019.

Bibliography

• Germplasm Resources Information Network: Rhododendron sect. Rhodora
• Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan.
• Chamberlain, D.; Royal Botanic Garden, Edinburgh (1996). The genus Rhododendron : it's classification & synonymy. Edinburgh: Royal Botanic Garden, Edinburgh. ISBN 1-872291-66-X. OCLC 34886265.
• Craven, L.A.; Goetsch, L.A.; Hall, B.D.; Brown, G.K. (2008). "Classification of the Vireya group of Rhododendron (Ericaceae)". Blumea – Biodiversity, Evolution and Biogeography of Plants. 53 (2): 435. doi:10.3767/000651908X608070.