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.

Trisetum thospiticum

HABIT Perennial; caespitose; clumped densely. Butt sheaths papery; glabrous. Culms erect; 20–50 cm long; 2–5 -noded. Culm-internodes distally pubescent. Ligule an eciliate membrane; 0.5–1 mm long; lacerate; obtuse. Leaf-blades 3–11 cm long; 2.3–4 mm wide. Leaf-blade surface pilose. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; oblong; 3.6–10 cm long; 1.3–3.5 cm wide. Primary panicle branches appressed; 1–2.5 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1.5–4 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 5.5–9.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.5–2 mm long; pubescent; with 0.6–0.8 mm long hairs. Floret callus pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 3.5–6.3 mm long; 0.75 length of upper glume; membranous; much thinner on margins; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume elliptic; 5–8 mm long; 0.8–1 length of adjacent fertile lemma; membranous; with hyaline margins; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 6–8 mm long; membranous; much thinner above; much thinner on margins; shiny; keeled; 5 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; geniculate; 6–10 mm long overall; with twisted column. Palea gaping; hyaline. Palea keels scaberulous.

FLOWER Anthers 3; 2.2–3.7 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: western Asia.

NOTES Aveneae. Fl Turk 1993.

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