Scirpus bisumbellatus Forssk., Fl. Aeg.-Arab. 1: 15. 1775; F. dichotoma auct. non (L.) Vahl, Enum. Pl. 2: 287. 1805; Hooper, in Townsend & Guest, Fl. Iraq.: Pl. 84. 1985. Zangheri, Fl. Ital. 2: 196. 1976 as F. dichotoma (L.) Vahl.

Greyish-green, small tufts forming annual, (3-)10-35 cm. Stem terete, 0.5-1 mm diam., glabrous. Leaves c. 1/2 of stem length; sheaths open, villous in upper parts; lowest bladeless, bicarinate, with scarious margins; ligule compact fringe of hairs; blades 0.5-1 mm wide, flat, adaxial side almost glabrous, abaxial side villous esp. in proximal parts, margins towards apex scabrous. Inflorescence to 5 cm diam., with 15-30 spikes, mostly solitary, occasionally a few sessile grouped together; lowest bract usually shorter than inflorescence; peduncles grooved. Spikes 3.5-4.5 x 1.3-1.5 mm, narrowly ellipsoid, more or less angular, acute, light brown to greyish brown; rachis brown to dark brown, with scarious wings; glumes 1.3-1.8 x c. 1 mm, ovate, glabrous or, occasionally, slightly hirsute, keeled, with prominent mid-nerve, arista conspicuous, margins widely scarious, slightly ciliate. Stamens 1, sometimes 0; filaments scarious, compressed; anthers c. 1 mm; style brown, c. 1 mm, flat, ciliate, stylopodium whitish, c. 0.25 x 0.25 mm, stigmas 2. Nut c. 0.8 x 0.7 mm, lenticular, widely obovoid, trabeculate, yellowish to almost white.

Fl. Per.: July – October, but may flower almost throughout the year.

Type: "Habitat in lociis littoreis insularum Niloticarum" 1761 Forsskål (C-Forssk.) microf. 96: 13-14!.

In moist, marshy places along rivers, ditches, irrigation channels, around lakes, alluvial meadows, rice fields, etc., partially as weed; 0-5500 ft; Distribution: From Western tropical and SE Africa to southern Europe, and eastwards to Madagascar, Pakistan, India, Malaysia, tropical Australia and New Zealand.

The name Fimbristylis dichotoma (see above) is sometimes still used for this taxon, although C.E.C. Fischer (Notes on the Flora of Madras: Part X. Kew Bull. p. 149. 1935) corrected its usage. It is also to be noted that according to Stewart (1972), Clarke (1898) used F. diphylla Vahl for F. dichotoma, although Clarke clearly aimed for two distinct species.