Plants shrub-like; rhizomes pachymorph, necks similar in length, up to 30 cm. Culms in a single dense clump (unicespitose), to 5 m tall and 2.5 cm in diam., erect, apically nodding to pendulous; internodes to 30 cm, terete, smooth, without fine purple spots, green to blue-grey with light persistent wax, becoming glossy, glabrous; nodes scarcely raised. Branches 3--7 per mid-culm node at first, without promontory, subequal, deflexed, lateral branch axes lacking subtending sheaths; buds at mid-culm broadly lanceolate to ovate, open at front (closed at culm base), 3--9 initials visible within. Culm sheaths usually long-triangular, papery and persistent, often with prominent dark spots around scattered bristles, apically loose; blades short, reflexed, deciduous; ligule often long-fimbriate. Leaf sheaths persistent; blade matt, thin, venation indistinctly tessellate. Synflorescence ebracteate, semelauctant; branching racemose to paniculate, erect, never unilateral, shortly-exserted from narrow subtending sheath. Spikelets several-flowered. Stamens 3. Stigmas 2-3. Named in honour of Professor Yi Tong-Pei, bamboo taxonomist from Sichuan who documented scores of new temperate bamboos.
Tongpeia is a temperate to subtropical genus that currently includes 3 species names for species native to Yunnan and Sichuan. They have morphological distinctions, and flowered at different times.
Tongpeia fungosa was the first species published, initially in Fargesia. The name was moved from Fargesia into Borinda because its inflorescences are open and unspathed. It was then separated from Borinda as a distinct genus, Tongpeia, on the grounds of both morphology and molecular phylogeny. This phylogeny inferred in Ye et al. (2019) is presented here with the genera recognised in this website classification superimposed upon it.
The real T. fungosa was in flower in China in 1980, and was described as having leaf sheaths ‘hairless, auricle tiny, long-shaped, edge with strong straight or slightly curved setae’, and in Flora of China as ‘auricles purple, falcate, small; oral setae erect’.
Tongpeia syrinx was raised in the west from seed sent from China in 1992/3 under the name Fargesia fungosa. It has slightly tomentose leaf sheaths with absolutely no auricle, but strong straight setae. It was/is grown in the west, especially in California, as Fargesia fungosa or Borinda fungosa.
Tongpeia arachnoides was sent as seed from China in 2011 and subsequent years under very many names, including Fargesia fungosa once again. It has partially pubescent leaf sheaths with very large falcate auricles with strong, wavy, widely spreading oral setae. Culm sheaths are very long, giving a blunt appearance to new shoots. Thus 3 different species have been referred to as fungosa, and they have been placed in 3 different genera.
Tongpeia is unlike Fargesia, but similar to Borinda, in that the flowers are in panicles or racemose panicles, and never in tight racemes, and the culms lack dark spots. The leaves are also usually thinner, less glossy, and lighter green. Unlike the culms of Borinda, which are finely ridged, the culms are smooth.
There are many Chinese species currently in Fargesia that do not belong in either Fargesia or Borinda, as shown by the phylogeny from molecular investigations reported by Ye et al. 2019. The publication of Tongpeia starts to deal with some of these species, which have varied characteristics, but the correct placement of them all will requires further research and will not be possible without more botanical fieldwork in China. The 2 known species in widespread cultivation in the west both have small very dark spots on the culm sheaths where bristles arise, and less distinct leaf blade vein tessellation than other temperate genera, as do the additional taxa under investigation.
Ye, X.Y., Ma, P.F., Yang, G.Q., Guo, C., Zhang, Y.X., Chen, Y.M., Guo, Z.H. and Li, D.Z. (2019). Rapid diversification of alpine bamboos associated with the uplift of the Hengduan Mountains. Journal of Biogeography 2019; 00: 1– 12 https://doi.org/10.1111/jbi.13723