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 martha-gonzaleziae

HABIT Perennial. Culms 75–100 cm long; 3 -noded. Culm-internodes striate; distally glabrous. Culm-nodes glabrous. Leaf-sheaths 3–10 cm long; mostly shorter than adjacent culm internode; striately veined; glabrous on surface; outer margin hairy. Ligule a ciliolate membrane; 0.5–1 mm long; glabrous on abaxial surface; truncate. Leaf-blades flat, or convolute; 10–30 cm long; 2–3.5 mm wide; stiff. Leaf-blade surface scabrous; rough on both sides.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted, or spiciform; oblong; 10–20 cm long; 1.5–2(–4) cm wide. Primary panicle branches 5–6 -nate; whorled at most nodes; 2–5 cm long. Panicle axis glabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels glabrous.

FERTILE SPIKELETS Spikelets comprising 2(–3) fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 7.5–9 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.4–1.5 mm long; pilose; with 1.5 mm long hairs. Floret callus pilose; obtuse. Floret callus hairs 1–1.2 mm long.

GLUMES Glumes persistent; similar; reaching apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 7.5–9 mm long; 1 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein scaberulous. Lower glume apex acute. Upper glume lanceolate; 7.5–9 mm long; 1.5 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scaberulous. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 5 mm long; membranous; shiny; without keel; 5 -veined. Lemma lateral veins excurrent, or extending close to apex. Lemma surface glabrous. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.33–0.5 way up back of lemma; geniculate; 5 mm long overall; with twisted column. Palea gaping; 5 mm long; hyaline.

FLOWER Lodicules 2; 0.5 mm long; 2-toothed. Anthers 3. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: Mexico.

NOTES Aveneae. Peterson & BFinot 2005.

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