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.

Brachiaria occidentalis

HABIT Annual; caespitose; clumped loosely. Culms decumbent; slender; 10–30 cm long; 3–6 -noded; without nodal roots, or rooting from lower nodes. Culm-internodes smooth; distally glabrous. Culm-nodes pubescent, or bearded. Lateral branches lacking, or sparse. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface, or pilose; with tubercle-based hairs; outer margin hairy. Ligule a ciliolate membrane; truncate. Leaf-blade base simple, or broadly rounded. Leaf-blades linear, or lanceolate; 1.5–5.5 cm long; 4–9 mm wide. Leaf-blade surface glabrous, or puberulous. Leaf-blade margins cartilaginous; scaberulous; tuberculate-ciliate; hairy at base. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 3–5; borne along a central axis; erect; unilateral; 3–5 cm long. Central inflorescence axis 2–4 cm long. Rhachis angular; scaberulous on margins.

Spikelets in pairs. Fertile spikelets pedicelled. Pedicels unequal; 0.5 mm long, or 1–2 mm long; glabrous, or ciliate; hairy at tip.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; compressed strongly; plano-convex; acute; 3–3.8 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.5–0.8 mm long; 0.1–0.2 length of spikelet; hyaline; without keels; 1–3 -veined. Lower glume lateral veins absent, or obscure. Lower glume apex obtuse. Upper glume ovate; 1.3–1.5 length of adjacent fertile lemma; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume apex obtuse.

FLORETS Basal sterile florets male, or barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; membranous; 5–7 -veined; obtuse. Palea of lower sterile floret 1 length of lemma. Fertile lemma elliptic; gibbous; 2.3–2.5 mm long; indurate; without keel. Lemma surface rugulose. Lemma margins involute. Lemma apex obtuse; mucronate. Principal lemma awn 0.2–0.4 mm long overall. Palea involute; indurate; without keels. Palea surface rugose.

FLOWER Anthers 3; 0.7–1.5 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid, or oblong; 1.5 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Gard & Hubb 1997.

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