Eleocharis caduca Schult.

Annual herb, tufted, 0.05-0.15 m high. Leaf blades absent. Culm scapose, terete, ridged, 0.8-1.2 mm in diam. Inflorescence a single, terminal, ovate spikelet, 2.0-5.5 x 1-2 mm, 4-8-flowered. Subtending bract 1, glume-like. Glumes broadly oblong when flattened, ± 2 mm long, keeled, keel non-excurrent. Perianth 6 or 7 whitish or reddish brown, barbate bristles of variable length, at least some longer than nutlet. Style branches 2. Flowering time Oct. Nutlet obovate, excluding style base 0.8-1.0 mm long, biconvex, shining, dark brown to black, crowned by persistent, triangular, whitish style base, surface smooth.