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 albicoma

HABIT Annual. Culms erect; 160–200 cm long. Culm-internodes terete; hollow; distally hispid. Culm-nodes pubescent, or bearded. Lateral branches lacking, or sparse. Leaf-sheaths 12–19 cm long; longer than adjacent culm internode; hispid; outer margin hairy. Ligule a ciliate membrane; 1–1.6 mm long. Collar pubescent. Leaf-blade base broadly rounded. Leaf-blades linear, or lanceolate; 18–24 cm long; 14–18 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface hispid. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes borne along a central axis; ascending; unilateral. Central inflorescence axis 22–30 cm long. Rhachis wingless; angular; hirsute on surface. Rhachis hairs 3–5 mm long. Spikelet packing irregular.

Spikelets in pairs, or in threes. Fertile spikelets pedicelled. Pedicels ciliate; with 3–5 mm long hairs.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; compressed slightly; 4.5–5.1 mm long; 1.6–1.8 mm wide; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 1.9–2.5 mm long; 0.33–0.5 length of spikelet; membranous; without keels; 3 -veined. Lower glume surface scabrous; rough at apex. Lower glume apex obtuse, or acute. Upper glume ovate; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume surface scabrous; rough at apex. Upper glume apex acute.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 3.7–3.8 mm long; 1 length of spikelet; membranous; 7 -veined; scabrous; rough at apex; glabrous. Fertile lemma ovate; 3.3–3.7 mm long; indurate; yellow, or light brown; without keel; 5 -veined. Lemma surface papillose. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate; without keels. Palea surface rugose.

FLOWER Anthers 3.

DISTRIBUTION South America: western South America.

NOTES Paniceae. Zuloaga 1998.

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