Monday, August 26, 2013

[Botany • 2013] Bergbambos & Oldeania • new genera of temperate Bamboos in the tribe Arundinarieae (Poaceae, Bambusoideae) from Africa


African bamboo Bergbambos tessellata
photo: Chris Stapleton.

Abstract

Two new monotypic genera, Bergbambos and Oldeania are described for African temperate bamboo species in the tribe Arundinarieae, after a comparison of their morphological characteristics with those of similar species from Asia. Morphological differences are supported by their isolated geographical distributions. Molecular evidence does not support the inclusion of these species in related Asian genera, recognising them instead as distinct lineages. New combinations Bergbambos tessellata and Oldeania alpina are made.

Keywords: Thamnocalamus, Yushania, Arundinarieae, new genus, Africa


Yushania alpina A tall culms arising separately, Rwenzori, Uganda photo: Peter Gill

Bergbambos Stapleton, gen. nov.
Type: Bergbambos tessellata (Nees) Stapleton comb. nov.
Basionym: Nastus tessellatus Nees, Arundinaria tessellata (Nees) Munro; Thamnocalamus tessellatus (Nees) Soderstrom & R.P. Ellis.

Name Bergbambos from the Afrikaans name (Bergbamboes) in South Africa.
This genus would appear to be monotypic, confined to the mountains of South Africa, Lesotho and Swaziland.


Oldeania Stapleton, gen. nov. 
Type: Oldeania alpina (K. Schum.) Stapleton comb. nov. 
Basionym: Arundinaria alpina K. Schum. Sinarundinaria alpina (K. Schum.) C.S. Chao & Renvoize; Yushania alpina (K. Schum.) W.C. Lin. 

Name Oldeania from the Maasai common name (Oldeani) in Tanzania.
Currently only the type species can be reliably placed in the genus, which thus has a distribution across tropical Africa from Cameroon in the west to E Africa, where it occurs from Ethiopia south to Tanzania. There is a possibility that species from Madagascar will be placed in this genus when they are better known, but they may be conspecific or even introduced. It provides important montane wildlife habitats and food, notably for the critically endangered Mountain Gorilla, Gorilla beringei beringei.
The holotype, G.A. Fischer 672, was destroyed by fire during the 1939–1945 World War. No trace of the type collection or any duplicate has been found in surviving components of the Berlin collections, nor in other herbaria, including the Hamburg collections taken to Russia and recently repatriated (Poppendieck pers. comm.). The likelihood of substantial infraspecific variation, the possibility of further species, and the lack of other collections from the type locality together make it inadvisable to select a neotype or epitype until new collections have been made.


Two New Bamboo Genera Found in Africa
Biologist Dr Chris Stapleton from the United Kingdom has described two new genera of African mountain bamboos.

Chris Stapleton. 2013. Bergbambos and Oldeania, new genera of African bamboos (Poaceae, Bambusoideae). PhytoKeys. 25: 87-103; doi: dx.doi.org/10.3897/phytokeys.25.6026