GrassBase - The Online World Grass Flora


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

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

Aira elegans

HABIT Annual; caespitose. Culms erect, or geniculately ascending; slender; 10–40 cm long. Ligule an eciliate membrane; 2–3 mm long; acute. Leaf-blades filiform; flat, or convolute; 2–4 cm long; 0.5–1 mm wide. Leaf-blade surface scaberulous; glabrous. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence a panicle.

Panicle open; obovate; effuse; 4–9 cm long; 2–5 cm wide. Primary panicle branches branching dichotomously. Panicle branches capillary; terete; smooth.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; terete; 5–13 mm long; 2–5 length of fertile spikelet; tip pyriform.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 1.5–2.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes suppressed between florets (florets arising at about the same level). Floret callus pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume ovate; 1.5–2.5 mm long; 1 length of upper glume; membranous; 1-keeled; keeled above; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1.5–2.5 mm long; 1.5 length of adjacent fertile lemma; membranous; 1-keeled; keeled above; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile florets all alike, or with the lowest dissimilar. Lowest fertile lemma muticous, or awned. Fertile lemma ovate; laterally compressed; lanceolate in profile; 1.5 mm long; cartilaginous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface scabrous. Lemma margins involute; covering most of palea. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.3–0.4 way up back of lemma; geniculate; 1.5–2 mm long overall; clearly exserted from spikelet; with twisted column.

FLOWER Lodicules 2; lanceolate; membranous. Anthers 3; 0.3–0.5 mm long. Stigmas 2.

FRUIT Disseminule comprising a floret.

DISTRIBUTION Europe: central, southwestern, southeastern, and eastern. Africa: north, Macaronesia, and western Indian ocean. Asia-temperate: Soviet Middle Asia, Caucasus, and western Asia. Australasia: Australia and New Zealand. North America: northwest USA, southwest USA, south-central USA, and southeast USA. South America: Brazil and southern South America.

NOTES Aveneae. Gr Maur.

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