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 pauciflora

HABIT Annual; caespitose. Culms geniculately ascending; 10–40 cm long; rooting from lower nodes. Culm-internodes 0.5–6 cm long; distally pubescent. Culm-nodes pubescent. Lateral branches sparse. Leaf-sheaths puberulous; outer margin hairy. Ligule a ciliate membrane; 0.5–0.8 mm long. Leaf-blade base cordate. Leaf-blades lanceolate; 2–9 cm long; 3–15 mm wide. Leaf-blade surface glabrous, or puberulous; densely hairy; hairy on both sides. Leaf-blade margins scabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes. Peduncle 1–20 cm long; pubescent above.

Racemes 3–4; borne along a central axis; unilateral; 2–53 cm long; bearing 3–7 fertile spikelets on each. Central inflorescence axis 5–9 cm long; puberulous. Rhachis wingless; angular; 0.25–0.3 mm wide; scabrous on margins. Spikelet packing lax; irregular; 1–2 -rowed.

Spikelets in pairs. Fertile spikelets sessile and pedicelled. Pedicels linear; 1.5–5 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; plano-convex; acute; 3–3.2 mm long; 1.3–1.4 mm wide; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; clasping; 1.3–1.6 mm long; 0.33–0.5 length of spikelet; membranous; without keels; 3–5 -veined. Lower glume lateral veins obscure; meeting at apex. Lower glume surface puberulous. Lower glume apex acute. Upper glume ovate; 3–3.2 mm long; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume lateral veins with cross-veins. Upper glume surface puberulous. Upper glume apex acuminate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 3–3.2 mm long; 1 length of spikelet; membranous; 5 -veined; puberulous; acuminate. Fertile lemma elliptic; 2.4–2.5 mm long; 1.2–1.3 mm wide; indurate; yellow; keeled; lightly keeled. Lemma surface rugulose; with distinct germination flap. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate; without keels. Palea surface rugose.

FLOWER Anthers 3; 0.5–0.6 mm long.

FRUIT Caryopsis ellipsoid; 1.5–1.6 mm long. Embryo 0.66–0.75 length of caryopsis. Hilum elliptic, or linear; 0.33 length of caryopsis.

DISTRIBUTION North America: Mexico.

NOTES Paniceae. Sanchez-Ken 2012.

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