The bamboos of Nepal and Bhutan. Part II: Arundinaria, Thamnocalamus, Borinda, and Yushania (Gramineae: Poaceae, Bambusoideae)

Abstract

This paper continues the systematic treatment of the bamboos of Nepal and Bhutan, covering four hardy temperate genera with semelauctant inflorescences and 3 stamens from the subtribe Arundinariinae Bentham. Arundinaria Michaux has leptomorph rhizomes, while Thamnocalamus Munro, Yushania Keng f., and the new genus Borinda have pachymorph rhizomes. The separation of these and related Sino-Himalayan genera is discussed. Sinarundinaria Nakai is treated as a synonym of Fargesia Franchet, a genus that is not known from the Himalayas. A new treatment of Himalayan Thamnocalamus species is given, including the description of two new subspecies of Thamnocalamus spathiflorus (Trin.) Munro, subsp. nepalensis and subsp. occidentalis, and one new variety, bhutanensis. T. aristalus is treated as a synonym of T. spathiflorus subsp. spathiflorus, and Fargesia crassinoda Yi is transferred and given new status as Thamnocalamus spathiflorus (Trin.) Munro var. crassinodus (Yi) Stapleton. Two new species of Borinda are described: B. chigar from West Nepal and B. emeryi from East Nepal. Six species of Fargesia from Tibet are transferred to Borinda, which thus comprises eight species.