Cyperus polystachyos Rottb., Descr. Pl. Icon. Progr.: 21. 1772; R.R.Stewart, l.c. 91; Haines & Lye, Sedges and Rushes E Afr.: Figs. 571-572. 1983. K.M. Matthew, Fl. Tamilnadu Carnatic 4: Pl. 694. 1988.

Perennial, 15-65 cm. Rhizome short, emitting stolons. Stem 1-2.5 mm diam., trigonous, grooved, smooth, greyish green. Leaves to half of stem; sheaths up to 15 cm, yellowish or grey-green, often with reddish tint, soft, mouth margin straight; blades up to 20 cm, flat or folded, keeled, grey-green, margin narrowly recurved, margins and keel scabrous towards the apex, apex short, flat or trigonous, scabrous. Inflorescence 20-50 mm diam., rounded or conical, either one cluster of spikes, or small anthelodium; 3-4 bracts foliose, longer than inflorescence, to more than 15 cm; primary branches up to 30 mm, tubular prophyll up to 6 mm, cluster of spikes tight, of to more than 20 digitately arranged spikes; spikes 10-15 x 1-1.5 mm, compressed, with 16-26 glumes; glume-like bract 0.5-0.6 mm, glume-like prophyll c. 0.7 mm; glumes 1.8-2.2 mm, strongly keeled, acute, mid-nerve area green, with one weak nerve on each side, sides scarious; rachis quadrangular, c. 0.3 mm wide, zig-zag, internodes c. 0.5 mm, with wide, rounded wings embracing the nutlet; connection of wings to glumes above not evident. Stamens 2. Nut c. 1 x 0.3 mm, bi-convex, sides almost parallel, apex blunt, surface reddish brown, very finely papillose.

Fl. Per.: January - June.

Type: India, ”In regione Malabarica”, König.

Coastal areas; in oases; rice-fields; Distribution: S Italy, Cap Verde Islands, Algeria, Libya south to S Africa, Madagascar, one record from Israel and S Iraq, Pakistan, coastal Pakistan and NW India east to Russian Far East, Japan, Taiwan, Australia, Fiji, N and S America.

Reported from Sind by C.B.Clarke (l.c.) and Kükenthal (l.c.). Koyama in Fl. Vitiensis 1: 259 (1979) cites Plukenet’s tab. 416, fig. 6 as ”holotype”. Rottboell’s protologue (1772) cites a König specimen, illustrated in Rottb., Descr. Icon. rar. Pl.: IX, fig. 1 (1773) and also Plukenet’s plate (1705), cited with question-mark in Rottb. (1773).