GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Lachnagrostis glabra

HABIT Annual. Stolons absent. Basal innovations extravaginal. Culms decumbent; 18–35 cm long. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane; 3–5 mm long; scaberulous on abaxial surface; erose; truncate. Leaf-blades 4–15 cm long; 1.5–2.5 mm wide. Leaf-blade surface scaberulous; rough adaxially. Leaf-blade margins scaberulous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle; deciduous as a whole. Peduncle scaberulous above; fracturing.

Panicle open, or contracted; lanceolate, or elliptic; 5–20 cm long; 1–6 cm wide. Panicle axis scaberulous. Panicle branches capillary; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 3–3.8 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous, or sparsely hairy. Floret callus hairs 0.1 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume elliptic; 3–3.8 mm long; 1 length of upper glume; membranous; much thinner on margins; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume elliptic; 3–3.8 mm long; 1.3 length of adjacent fertile lemma; membranous; with hyaline margins; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma oblong; 1.8–2.5 mm long; hyaline; without keel; 3–5 -veined. Lemma lateral veins obscure. Lemma surface glabrous. Lemma apex erose; truncate; muticous, or awned; 1 -awned. Principal lemma awn subapical; straight; 0–1.2 mm long overall. Palea 1 length of lemma; hyaline; 2 -veined. Rhachilla extension 0.3–0.5 mm long; sparsely hairy; with 0.4–0.8 mm long hairs.

FLOWER Lodicules 2; membranous; acute. Anthers 3; 0.5–0.9 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Australasia: New Zealand.

NOTES Aveneae. Edgar 2000.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.