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.

Aira cupaniana

HABIT Annual. Culms erect, or geniculately ascending; 10–35 cm long; 2–3 -noded. Leaves mostly basal. Ligule an eciliate membrane; 1–5 mm long. Leaf-blades 1–6 cm long; 0.5–1 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 2–12 cm long. Primary panicle branches ascending, or spreading. Panicle branches flexuous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; terete; tip globular.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; without rhachilla extension. Spikelets oblong to ovate; laterally compressed; 1.3–2.3 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; reaching apex of florets, or exceeding apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume ovate; 1.3–2.3 mm long; 1 length of upper glume; membranous; 1-keeled; keeled above; 1–3 -veined. Lower glume primary vein scaberulous. Lower glume apex obtuse. Upper glume ovate; 1.3–2.3 mm long; 1–1.2 length of adjacent fertile lemma; membranous; 1-keeled; keeled above; 1–3 -veined. Upper glume primary vein scaberulous. Upper glume apex obtuse.

FLORETS Fertile florets all alike, or with the lowest dissimilar. Lowest fertile lemma muticous. Fertile lemma ovate; laterally compressed; lanceolate in profile; 1.3–2 mm long; cartilaginous; dark brown; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface scaberulous; rough above. Lemma margins involute; covering most of palea. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.25 way up back of lemma; geniculate; 1.8–2.5 mm long overall; with twisted column. Palea elliptic; 0.7 length of lemma; cartilaginous; 2 -veined. Palea apex obtuse.

FLOWER Lodicules 2; lanceolate; membranous. Anthers 3; 0.1–0.25 mm long. Stigmas 2; protandrous; laterally exserted.

FRUIT Caryopsis with adherent pericarp; fusiform; isodiametric; biconvex; estipitate; without sulcus; 1 mm long; smooth; apex unappendaged. Embryo 0.2 length of caryopsis. Hilum punctiform. Endosperm farinose. Disseminule comprising a floret.

DISTRIBUTION Europe: southwestern and southeastern. Africa: north and south. Australasia: Australia and New Zealand.

NOTES Aveneae. Gr Extremad 1993.

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