Abstract: A new bamboo genus，Gaoligongshania D．Z．Li，Hsueh et N．H．Xia is described here to accommodate Arundinaria megathyrsa Hand．-Mazz．from Northwest Yunnan，China after comprehensive collection and study of the species．The new genus is certainly a member of the subtribe Arundinarinae Bentham in the sense of Clayton & Renvoize (1986) and Soderstrom & Ellis (1987) and may be a link between Indocalamus and the Thamnocalamus complex(the so-called alpine bamboos)．Its inflorescence is determinate(semelauctant)with normal grass spikelets，large and conspicuously auricled leaves and single branch complements which are as thick as culms．Gaoligongshania related to Indocalamus but has sympodial rhizomes，clustered culms，very large inflorescences，linear spikelets and three stigmas．Itis sometimes epiphytic in habit．It also shows affinity with the Thamnocalamus complex with the same inflorescence and rhizome types．The complex，however，is one of the most difficult groups in defining bamboo genera and was considered as an independent subtribe(Keng f.，1982)or has even been put into the genus Arundinaria in the broadest sense(Soderstrom ＆ Ellis, 1988). Even then,Gaoligongshania can still be considered distinct because of its branch pattern and unusual inflorescence and spikelets. Although Gaoligongshania is superficially similar to Monocladus Chia et al. in its vegetative state,it belongs to a different subtribe, and its reproductive state is very different from Monocladus. In that genus, the inflorescence is indeterminate (iterauctant) and is composed of pseudospikelets with 6 stamens and conspicuous ovary appendages.

Key words: Gaoligongshania D. Z. Li, Hsueh et N. H. Xia, Bambusoideae