Isolepis fluitans

Slender aquatic or terrestrial perennial. Aquatic plants with stems floating at the surface or submerged and creeping, elongated, branching at the nodes, to over 1 m long; terrestrial plants creeping or forming more or less compact tufts, to 10 cm high. Spikelets solitary,ellipsoid to elliptic-ovoid, 5–10(–15)-flowered, 3–5 mm long; lowest involucral bract shorter than to far exceeding spikelet, glume-like to leaf-like; glumes obtuse, conspicuously numerous-nerved, straw-coloured, sometimes with red-brown patches, 1.7–2.8 mm long; stamens 2 or rarely 3; anthers 0.5–1.0 mm long; style 2-fid. Nut plano-convex, with angles not well-defined, broad-obovoid to ellipsoid, smooth, minutely reticulate, shining, grey-brown to dark brown, from one-half to three-quarters as long as glume, 1.4–1.8 mm long, c. 1 mm diam. Flowers spring–summer.