葫芦草 hu lu cao

Polytoca massiei (Balansa) Schenck ex Henrard ["massii"].

Annual. Culms loosely tufted, up to 50 cm tall, much branched, nodes bearded. Leaf sheaths papery, keeled, loose, slightly inflated, sparsely hairy; leaf blades narrowly lanceolate, flat or folded, thin, ca. 9–30 × 0.8–1.4 cm, glabrous or sparsely hairy with tubercle-based hairs, margins smooth or scaberulous, apex acuminate; ligule 0.5–1.5 mm. Racemes in spathate clusters of 2–4, each 2–8 cm; peduncles funnel-shaped with deep cupular apex straight across rim. Female sessile spikelets 1–3, 7–10 mm; lower glume hard, rounded, with 2 conspicuous transverse constrictions, lower margins abutting internode, abruptly contracted above into keeled, broadly winged beak; pedicelled spikelet rudimentary, comprising only a 1.5–4 mm lower glume. Male spikelet pairs 1–2 on short internodes, encircled by uppermost female spikelet; male sessile and pedicelled spikelets 2.5–5 mm.

Meadows. Hainan [Laos, Thailand, N Vietnam].

This species is very similar to Chionachne punctata (R. Brown) Jannink (Sclerachne punctata R. Brown), from Indonesia, and the two have been confused. Chionachne punctata is a taller plant with longer leaf blades and also differs in having peduncles with an oblique, apical rim and an asperulous sessile lower glume with more broadly overlapping margins.