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.

Briza calotheca

HABIT Perennial; caespitose. Basal innovations extravaginal. Culms erect; 60–150 cm long; 2 -noded. Culm-nodes glabrous. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 0.8–2.3 mm long. Leaf-blades flat; 9–30 cm long; 2–10 mm wide. Leaf-blade midrib keeled beneath. Leaf-blade surface ungrooved; scabrous; rough adaxially; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; 10–35 cm long; contracted about primary branches. Primary panicle branches 4–20 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2–20 mm long; puberulous.

FERTILE SPIKELETS Spikelets comprising 3–7 fertile florets; with diminished florets at the apex. Spikelets orbicular; laterally compressed; 3.5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.3–0.5 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 1.9–3 mm long; 0.9 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein ciliolate. Lower glume surface scabrous. Lower glume apex acute. Upper glume ovate; 2.2–3.5 mm long; 0.75–0.85 length of adjacent fertile lemma; membranous; 1-keeled; 5 -veined. Upper glume primary vein ciliolate. Upper glume surface scabrous. Upper glume apex acute.

FLORETS Fertile lemma oblate; 2.8–4 mm long; coriaceous; much thinner on margins; keeled; 5 -veined. Lemma surface scaberulous. Lemma margins eciliate, or ciliolate; hairy at base. Lemma apex mucronate. Palea lanceolate, or elliptic; 2.2–2.7 mm long; coriaceous; 2 -veined. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; lanceolate; 0.6–0.7 mm long; membranous; acute. Anthers 1(–3); 1–1.7 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; obovoid; trigonous; 1.6 mm long. Hilum elliptic.

DISTRIBUTION South America: Brazil and southern South America.

NOTES Poeae. Mathei 1994.

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