Sunday, July 18, 2021

[Botany • 2021] Rhododendron tephropeploides & R. chunii subsp. vietnamense (Ericaceae) • Two New Taxa of Rhododendron from Northwest Vietnam


Rhododendron tephropeploides  R.A.Baines & D.F.Chamb.

in Baines, Chamberlain, et al., 2021. 


ABSTRACT
Two new taxa from Vietnam are described and illustrated: Rhododendron tephropeploides, in subsection Tephropepla, and R. chunii subsp. vietnamense, in subsection Tsutsusi.

Keywords: Ericaceae, Phan Xi Păng, Rhododendron chunii subsp. vietnamenseRhododendron tephropeploides, Vietnam


Rhododendron tephropeploides  R.A.Baines & D.F.Chamb., sp. nov.
 RBGE accession no. 20150482 flowering at Logan Botanic Garden.
Photographs: R. A. Baines.

Rhododendron tephropeploides R.A.Baines & D.F.Chamb., sp. nov.
 (subsect. Tephropepla)

Similar to the allied Rhododendron tephropeplum Balf.f. & Farrer, a species from Northeast India, northern Myanmar and Southwest China, but differs in the dimorphic scales on the lower leaf surfaces; the smaller, 1-mm calyx lobes; the larger funnel-shaped, whitish to pale pink 30–35 mm corollas that are glabrous on the outer surfaces; and the glabrous stamens.  

 Ecology. Temperate montane cloud forest, in wet thin soil with high humus content and high humidity. The surrounding vegetation is characterised by Hydrangea, Illicium and Rhododendron.


Rhododendron chunii W.P.Fang subsp. vietnamense R.A.Baines & D.F.Chamb., subsp. nov.
(subsect. Tsutsusi)

Rhododendron chunii subsp. chunii differs from the new subspecies in the young stems that bear appressed bristles that apparently lack the stipitate glands of subsp. vietnamense, and in the outer surface of the corolla tube that is glandular.

Ecology. Temperate montane cloud forest, in wet thin soil with high humus content and high humidity. The surrounding vegetation is characterised by Enkianthus, Pieris and Rhododendron


R. A. Baines, D. F. Chamberlain, V. D. Nguyen and B. H. Quang. 2021.  Two New Taxa of Rhododendron (Ericaceae) from Vietnam. EDINBURGH JOURNAL OF BOTANY. 78, 363. DOI:  10.24823/EJB.2021.363