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.

Trisetaria dufourei

HABIT Annual; caespitose. Culms erect, or geniculately ascending; 10–35 cm long. Culm-internodes distally glabrous, or pubescent; with reflexed hairs. Leaf-sheaths pubescent; with reflexed hairs. Ligule an eciliate membrane; 1 mm long; truncate. Leaf-blades 2–5 cm long; 1–3 mm wide. Leaf-blade surface pubescent; hairy on both sides.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; lanceolate, or ovate; continuous, or interrupted; 2–6 cm long; 1–2.5 cm wide. Panicle axis pubescent. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels pubescent.

FERTILE SPIKELETS Spikelets comprising 2–4 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1 mm long; pubescent; with 0.5 mm long hairs. Floret callus pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume linear; 3–5 mm long; 0.7–0.8 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein scabrous. Lower glume apex acuminate. Upper glume lanceolate; 4.5–6.5 mm long; 1.1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 4–6 mm long; membranous; keeled; 3–5 -veined. Lemma surface scaberulous. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.66 way up back of lemma; geniculate; 5–7 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 1–2 mm long; shorter than principal. Palea gaping; linear; 3–4 mm long; hyaline. Palea keels scabrous. Palea apex dentate; 2 -fid.

FLOWER Anthers 3; 2 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Europe: southwestern.

NOTES Aveneae. Paunero 1993.

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