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.

Brachiaria orthostachys

HABIT Annual. Culms 20–60 cm long. Culm-internodes distally pubescent. Culm-nodes pubescent. Leaf-sheaths pubescent. Ligule a fringe of hairs. Leaf-blades 3–8 cm long; 2–7 mm wide. Leaf-blade surface pubescent; densely hairy; hairy on both sides.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 4–8; borne along a central axis; unilateral; 1–4 cm long. Central inflorescence axis 5–10 cm long; puberulous to pilose. Rhachis wingless; angular; puberulous on surface to pilose on surface. Spikelet packing adaxial; regular; 2 -rowed.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels oblong; 1 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; compressed slightly; acute; 2.5–3.5 mm long; falling entire. Rhachilla internodes elongated between glumes.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.5 length of spikelet; membranous; without keels; 5 -veined. Lower glume apex acute. Upper glume oblong; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume surface glabrous. Upper glume apex acute.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; oblong; 1 length of spikelet; membranous; 5 -veined; glabrous; acute. Fertile lemma oblong; 3 mm long; indurate; without keel. Lemma surface rugulose. Lemma margins involute. Lemma apex obtuse. Palea involute; indurate; without keels. Palea surface rugose.

DISTRIBUTION Africa: west tropical and northeast tropical.

NOTES Paniceae. WDC.

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