Rhizomes leptomorph; culms hollow, 3–15 m, 1–15 cm in diameter, erect; culm leaf sheaths well developed, glabrous, auricles absent, fimbriae absent, oral setae absent; culm leaf blades reflexed, deciduous; branching intravaginal; node with two subequal, divergent branches, thorns absent, supra- and infra-nodal bands of short soft white hairs absent; internodes profoundly flattened or grooved on one side above branches; synflorescences racemose; pseudospikelets comprising 1 subtending bract, 2-keeled prophyll, 0 or 1 gemmiparous bract, 2–6 enlarged scaly bracts and 2–7 spathiform bracts, 2–7 florets, glabrous; palea 2-keeled, lemma glabrous, lodicules 3, stamens 3; fruit a basic caryopsis (Fig. 3A–F). Introduced Asiatic genus (Fig. 9C–D).

1. Culms 3–7 m, 1–5 cm in diameter; internodes 15–30 cm, usually some nodes strongly shortened and commonly ventricose at the base of the culm....................................................................................................................................................................... P. aurea

1. Culms 6–15 m, 6–15 cm in diameter; internodes 20–40 cm, not shortened or ventricose at basal nodes.................. P. bambusoides