Agrostis imbecilla Zotov
≡A. tenella Petrie, T.N.Z.I. 22: 442 (1890) non Hoffm. (1800);
Holotype: WELT 69601! D. P[etrie] Macraes, c. 1800 ft, Waihemo Co, Otago, Feby 1889.
Very slender, lax, perennial tufts, 15-35 cm, with long, very slender, spike-like panicles on slender culms much overtopping leaves; branching extravaginal. Leaf-sheath narrow, membranous, light creamish brown to reddish, glabrous, distinctly ribbed. Ligule 0.8-1.6 mm, obtuse, often erose, abaxially glabrous. Leaf-blade 2-13 cm × 0.2-0.4 mm diam., involute, filiform, flaccid, abaxially finely striate and, in young leaves, finely scabrid, later smooth, adaxially scabrid on ribs; margins scabrid, tip fine, blunt. Culm almost filiform, erect or geniculate at base, internodes glabrous. Panicle (2.5)-5-9 cm × 2-3 mm, contracted, extremely narrow-linear; rachis and few short erect branches and pedicels sparsely, finely scabrid, often pale purplish. Spikelets 1.5-2.4 mm, pale greenish purple to straw coloured. Glumes ± equal, lanceolate, minutely scabrid on keel and on margins near acute tip. Lemma 1.5-1.9 mm, at times ≈ glumes, glabrous, faintly 5-nerved, ovate-oblong, apex denticulate, awnless, or rarely a few lemmas subapically awned, awn straight, fine, up to 1 mm, scarcely projecting beyond glumes. Palea 0.1-0.2 mm, ovate. Lodicules 0.3-0.4 mm. Callus with few very minute hairs. Anthers 0.6-1 mm. Caryopsis 1-1.4 × 0.3 mm.
N.: one record from Upper Moawhango R., Kaimanawa Mts; S.: scattered in Canterbury and Otago. Tussock grassland in inland, montane to subalpine regions, often in damp places.
Endemic.
