Scirpus setaceus L.
Forming a dense, bright green turf or in small ± circular patches, 3-15- (20) cm high; rhizome short, very slender. Stems erect, terete, filiform. Leaves much < stems,± 0.5 mm wide, few; sheaths hyaline, light brown often reddish towards base. Inflorescence apparently lateral, of 1-2 spikelets; bract > spikelets, filiform. Spikelets 2-4 mm long, ovate. Glumes slightly < 1.5 mm long, striate, dark brown with green midrib, obtuse, strongly keeled. Hypogynous bristles 0. Stamens 2. Stigmas 3. Nut slightly < 1 mm long, ± biconvex, brown, shining, minutely apiculate, with noticeable longitudinal ribs and fine transverse bars between ribs.
N. Scattered localities southwards from Egmont, Volcanic Plateau and Lake Rotorua. S. Nelson; Westland; Canterbury; Southland; scattered elsewhere. In damp hollows, sandy flats or lake edges. (Europe, Asia, Africa)
First record: Allan 1935:3.
First collection: "Ashburton, H. H. Allan, end Dec., 1919, sandy hollows on riverbed" (AK 2116, 62090).
Very similar in general appearance to the native S. cernuus, but is easily distinguished from that and all other native spp. by the longitudinal ribs of the nut.
