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.

Trisetum tamonanteae

HABIT Perennial; caespitose; clumped densely. Culms erect; (5–)15–25(–30) cm long; without nodal roots, or rooting from lower nodes. Culm-internodes distally glabrous, or pilose; with reflexed hairs. Culm-nodes glabrous. Lateral branches lacking, or sparse. Leaf-sheaths longer than adjacent culm internode; striately veined; pubescent. Ligule an eciliate membrane; lacerate; truncate. Leaf-blades 3.5–14 cm long; 2.8–6 mm wide; stiff. Leaf-blade midrib conspicuous. Leaf-blade surface pubescent; hairy on both sides. Leaf-blade apex apiculate.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; ovate; interrupted; 3–7(–9) cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising (2–)3–4(–5) fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 4–5.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 3.4–4.5 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 lanceolate; 1.3 length of adjacent fertile lemma; membranous; with hyaline margins; 1-keeled; 3 -veined. Upper glume surface scabrous; rough on veins. Upper glume margins scabrous. Upper glume apex acute; muticous, or mucronate.

FLORETS Fertile lemma lanceolate, or oblong; (2.6–)3–3.8 mm long; membranous; shiny; keeled; 5 -veined. Lemma lateral veins excurrent. Lemma surface scabrous; glabrous, or pilose. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.66–0.75 way up back of lemma; straight, or curved, or geniculate; 1.8–4.5 mm long overall. Palea 2.3–3 mm long. Palea keels scabrous.

FLOWER Lodicules 2; 0.3–0.6 mm long; 2-toothed. Anthers 3; 0.8–1.8 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; oblong; 1.6–2.2 mm long; light brown. Hilum punctiform.

DISTRIBUTION Africa: Macaronesia.

NOTES Aveneae. Rodriguez & Scholz 2013.

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