Plants shrub-like, densely clumping; rhizomes pachymorph, necks to 20 cm. Culms unicespitose to 3(-7) m tall, often basally curved, apically erect to nodding, 1–2 cm thick, hollow; internodes terete, not finely ridged, thick-walled. Branch complement 5 to many per node, erect to spreading, open at the front, sheaths or sheath scars between lateral branches absent. Culm sheaths persistent, blade usually erect. Leaf sheaths persistent, ligule ciliate, oral setae irregular, delicate; blade with evident tessellation abaxially, orientation varied. Synflorescence semelauctant, a dense, contracted raceme, not unilateral, supported by persistent sheaths. Pseudospikelets with 1(-2) fertile florets; glumes 2, more or less equal to the lemmas, unawned; lemmas not distally ciliate, unawned, not mucronate; palea not bifid, keels ciliate, shorter than the lemma; anthers 3; ovary glabrous; style branches 3. Name from Afrikaans, Bergbamboes.
Bergbambos, including only the S African species B. tessellata, is a genus native to S Africa, Lesotho and Swaziland, with condensed spatheate synflorescences. It has been considered to include Fargesia and Himalayacalamus, but differs substantially in branching and bud characters (Stapleton 1994), having fewer branches, all subtended by sheaths. Placement of B. tessellata in Thamnocalamus by Soderstrom & Ellis (1982), largely on the basis of leaf anatomical characters, was unsatisfactory, as it shared more important characters with Fargesia than Thamnocalamus, from which it differs in its more cylindrical spikelet arrangement and the more irregular arrangement of its leaf blades and oral setae.
Soderstrom, T.R. ,& Ellis, R.P. (1982). Taxonomic status of the endemic South African bamboo, Thamnocalamus tessellatus. Bothalia 14(1): 53–67.
Stapleton, C.M.A. (1994) The bamboos of Nepal and Bhutan, Part 2: Arundinaria, Thamnocalamus, Borinda, and Yushania. Edinburgh J. Bot. 51: 275–295.
Stapleton CMA (2013) Bergbambos and Oldeania, new genera of African bamboos (Poaceae, Bambusoideae). PhytoKeys 25: 87–103. doi: 10.3897/phytokeys.25.6026
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