Flora of New Zealand Series

Isolepis basilaris Hook. f. Handbk N.Z. Fl.  1864,  302.

I. novae-zelandiae Col. in T.N.Z.I.  21,  1889,  102.

Type locality: Ngaruroro R., Hawke's Bay. Type: K, Colenso; isotype at WELT.

Dwarf, dense, moss-like tufts 3–9 cm. across, bright green above, reddish brown below. Rhizome < 1 mm. diam., much branched; sheathing bract at each node loose, membr., with red nerves. Culms < 1.5 rarely up to 3 cm. long, < 0.5 mm. diam. Lvs 1–2 on each branch, much > culms, 0.5–4–(6) cm. long, < 0.5 mm. wide, setaceous, plano-convex; sheath membr., red-nerved. Infl. an apparently lateral, single spikelet, or rarely 2, hidden among the lvs, pale green, occ. with red markings; subtending bract lf-like, channelled, very much > culm from which it arises and almost = lvs. Spikelets 2.5–3.5 × 1.5–2 mm., elliptical or oblong. Glumes 1–2 mm. long, ovate, elliptical, obtuse, white and membr., or with patches of red on the sides; keel thick, green, occ. slightly excurrent. Hypog. bristles 0. Stamens 2, rarely 3. Style-branches 2, occ. 3. Nut c. 0.5 × 0.5 mm., c. ⅔ length of glume, obovoid to suborbicular, plano-convex, dorsally rounded, noticeably apiculate, red-brown to dark brown, almost black, surface often shining but distinctly reticulate.

DIST.: N. Hawke's Bay, Wellington at Tangimoana and Himatangi. S. Nelson, Westland, Canterbury, Otago and Southland.

In damp sand on margins of inland lakes to c. 700 m. altitude, sometimes nearer the coast on river and salt flats.

I. novae-zelandiae. Colenso gives the type locality as "sides of watercourses in low grounds, Hawke's Bay", citing himself (1880) and Mr. Hamilton (1887) as collectors. WELT 24305 is from Waitangi, Hawke's Bay, Hamilton, Jan., 1888. Colenso described I. novae-zelandiae as having 3 stamens; in WELT 24305 the lower glumes of the spikelets have 3 stamens.

The very short culms with the spikelets hidden among the lvs, and the very dark brown nuts are characteristic of this small Scirpus; occasional plants with elongated culms are difficult to distinguish from S. caligenis if fr. is immature.