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.

Arrhenatherum longifolium

HABIT Perennial; caespitose. Culms 50–120 cm long. Culm-nodes bearded. Leaf-sheaths pilose. Ligule an eciliate membrane; 1–2 mm long; pubescent on abaxial surface; truncate. Leaf-blades flat, or convolute; 15–30 cm long; 2–5 mm wide. Leaf-blade surface ribbed; scabrous; rough adaxially; pilose. Leaf-blade margins scabrous. Leaf-blade apex hardened.

INFLORESCENCE Inflorescence a panicle. Peduncle scaberulous above.

Panicle open; lanceolate; dense; 5–15 cm long. Primary panicle branches bearing spikelets almost to the base. Panicle axis scabrous. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels tip widened.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 6–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes elongated below proximal fertile floret. Floret callus pilose. Floret callus hairs 0.1 length of lemma.

GLUMES Glumes persistent; dissimilar; reaching apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 5–6 mm long; 0.75 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein scabrous. Lower glume lateral veins obscure. Lower glume apex acuminate. Upper glume lanceolate; 6–7 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume apex acuminate.

FLORETS Basal sterile florets male; with palea; attached to and deciduous with the fertile. Lemma of lower sterile floret elliptic; 7–9 mm long; chartaceous; much thinner above; pubescent; dentate; 2 -fid; acute, or acuminate; awned. Awn of lower sterile floret dorsal; arising 0.66 way up back of lemma; geniculate; 7–9 mm long. Fertile lemma elliptic; 6–7 mm long; chartaceous; much thinner above; without keel; 5–7 -veined. Lemma surface pubescent. Lemma apex acuminate; mucronate, or awned; 1 -awned. Principal lemma awn subapical. Palea 4–5 mm long. Palea keels ciliolate.

FLOWER Anthers 3; 3–4 mm long. Ovary pubescent all over.

FRUIT Caryopsis with adherent pericarp; oblong; dorsally compressed; sulcate on hilar side; 2.5–3 mm long. Embryo 0.1 length of caryopsis. Hilum linear; 0.33 length of caryopsis.

DISTRIBUTION Europe: southwestern. Africa: north.

NOTES Aveneae. Fl Afr N 1993.

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