Brachiaria atrisola

HABIT Annual. Culms geniculately ascending; 10–60 cm long; 1–6 -noded. Culm-nodes glabrous. Lateral branches ample. Leaf-sheaths keeled; glabrous on surface, or pubescent; outer margin glabrous, or hairy. Ligule a fringe of hairs; 0.8–1.4 mm long. Collar glabrous. Leaf-blades linear, or lanceolate; 3–15 cm long; 4–102 mm wide. Leaf-blade surface glabrous. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–4; borne along a central axis; unilateral; 1.5–6 cm long; bearing 6–16 fertile spikelets on each. Central inflorescence axis 4–15 cm long. Rhachis narrowly winged; flattened; 1–1.5 mm wide; scabrous on margins. Spikelet packing adaxial.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels reduced to a stump.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; compressed slightly; obtuse; 3.6–4.5 mm long; 1.9–2.3 mm wide; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume oblate; clasping; 0.8–1.6 mm long; 0.25–0.33 length of spikelet; hyaline; without keels; 7–11 -veined. Lower glume apex truncate. Upper glume elliptic; 1 length of spikelet; membranous; without keels; 9 -veined. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 5 -veined; obtuse. Fertile lemma elliptic; 3.4–4.3 mm long; indurate; without keel. Lemma surface rugulose. Lemma margins involute. Lemma apex obtuse; mucronate. Palea involute; indurate; without keels.

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Webster 1995.

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