Flora of New Zealand Series

Isolepis crassiuscula Hook. f. Fl. Tasm.  2,  1858,  86, t. 143 A.

Original localities: Tasmanian. Also recorded from New Guinea and Australia.

Rhizome much elongated, branched and rooting at the nodes. Culms (2)–4–8–(15) cm. long, slightly < 1 mm. diam., rigid, erect, us. lfy. Lvs 4–6 cm. long, slightly < 1 mm. wide, <, = or > culms, narrow-linear, lamina flattened, tip subobtuse; lowermost lf on branch bract-like with pale membr. sheath to 4 mm. wide. Infl. a solitary spikelet, or very rarely 2, terminal and appearing so, pale green, flecked with red; subtending bract 0. Spikelets (3)–5.5–6.5–(8) × (2)–3–5 mm., oblong or ovoid. Glumes 2–4 mm. long, broadly ovate, obtuse, finely nerved, green at the centre, red-purple towards the margins. Hypog. bristles 0. Stamens 3. Style-branches 2. Nut c. 1.5 × 1 mm., obovate, much compressed, margins slightly thickened, minutely apiculate, grey.

DIST.: N. Volcanic Plateau.

Semi-aquatic subalpine plant, rooting in mud; at altitudes of c. 1,000 m.

For many years this sp. and S. fluitans were regarded in N.Z. as forms of the Australian S. lenticularis (R. Br.) Poir. though Cheeseman (Man. N.Z. Fl. 1925, 220) suspected that he had included 2 spp. under S. lenticularis.