Plinthanthesis urvillei Steud.

Culms 0.45–0.8 m high. Inflorescences 6–17 cm long. Spikelets 6–8.4 mm long, with 2–4 florets. Glumes equalling or slightly exceeding florets, acuminate; lower glume 6–8 mm long, 3-nerved, scaberulous along keels. Lemma: body 1.8–2.3 mm long; lobes 1.6–2.1 mm long (2–2.4 mm long including setae), marginally shorter than body, partially fused to the awn; lobe setae sometimes present, to 0.8 mm long; awn present, 4–4.5 mm long; awn column with 1 or 2 twists in older florets, 1.2–1.6 mm long. Palea 3–4 mm long. Anthers 2.1–3 mm long. Caryopsis 1.3–1.4 mm long.