Rhynchospora perrieri Cherm.

A slender annual 10-50 cm tall with a sparse root system. Leaves long and flexuose, set all along the culm, scabrous at least on margin and midrib near the apex. Inflorescence usually with 3-4 rather dense contracted elongate groups of spikelets only just protruding from the leaf-sheaths. Spikelets 3.5-5.0 mm long, brown, 1-2 flowered. Stamens 2. Style with 2 long branches. Nutlets strongly transversely rugose, as mature almost black; style-base decurrent on the nutlet.

Edge of swamps.