Brachiaria megastachya

HABIT Perennial. Culms 120–200 cm long. Culm-nodes glabrous. Leaf-sheaths glabrous on surface. Ligule a ciliate membrane; 1–1.5 mm long. Leaf-blade base broadly rounded. Leaf-blades lanceolate; 6–12 cm long; 8–10 mm wide. Leaf-blade surface pubescent; hairy adaxially. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 8–12; borne along a central axis; unilateral; 5–20 cm long. Central inflorescence axis 10–20 cm long; pilose. Rhachis wingless; angular; pubescent on surface. Spikelet packing distant; irregular.

Spikelets solitary, or in pairs, or in threes. Fertile spikelets sessile and pedicelled. Pedicels filiform; 1–12 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; compressed slightly; acute; 3.8–3.9 mm long; 1.4–1.5 mm wide; falling entire. Spikelet callus square; incorporating lowest rhachilla internode with adnate lower glume; 0.5 mm long.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; clasping; 1.8–2.2 mm long; 0.5–0.6 length of spikelet; membranous; without keels; 3–5 -veined. Lower glume apex acute. Upper glume ovate; 1 length of spikelet; membranous; without keels; 5–7 -veined. Upper glume apex obtuse, or acute.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; membranous; 5 -veined; ciliate on margins; acute. Fertile lemma elliptic; 3.2–3.4 mm long; 1.1–1.3 mm wide; indurate; without keel. Lemma surface papillose. Lemma margins involute. Lemma apex acute. Palea involute; indurate; without keels.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Zuloaga.

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