Flora of New Zealand Series

 C. thomsonii Petrie in T.N.Z.I. 18, 1886, 298 non Boott Ill. Car. 1, 1858, 1, t. 1.

Type locality (for C. thomsonii): Mt Pisa, 5,500–6,000 ft. Lectotype: WELT, 21489, D. Petrie.

Shortly rhizomatous; tufts squat, coarse-lvd, pale green, 2–7 cm. tall. Rhizome c. 2 mm. diam., woody, covered by fibrous remains of lf-sheaths. Culms 2–3–(5) cm. tall, < lvs and almost entirely hidden by lf-sheaths, triquetrous, scabrid; basal sheaths grey-brown or chestnut. Lvs 2–6 cm. × 1–3 mm., often almost distichously arranged, channelled, coriac., margins and keel minutely scabrid, tapering to a ± acute tip; sheaths dull brown, membr., ± = lamina in length. Infl. an ovate, triangular, brownish head, c. 7 × 7 mm., with 2–4 congested spikes, the lowermost rarely subtended by a lf-like bract. Spikes androgynous, 4–6 mm. long, male fls at top of spike, very rarely at base. Glumes ± = utricles, ovate, acute, membr., midrib short, green, keel of lowermost glumes occ. scabrid. Utricles c. 3 × 2 mm., plano-convex, elliptic-ovoid, ± papillose, nerved, dark brown with pale brown conspicuous wings, margins strongly scabrid; beak narrow, < 1 mm. long with a bifid oblique orifice; stipe very minute. Stigmas 2. Nut c. 1.5 mm. long, biconvex, smooth, brown; styles persistent.

DIST.: S. Old Man Range, South Canterbury; and in mountains of Central Otago from 1,500–1,860 m. altitude.

The relatively wide, coriac. lvs and short culms almost hidden within the lf-sheaths make this rhizomatous sp. very distinct.