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.

Tripogon borii

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Culms erect; 30–60 cm long; 2–3 -noded. Culm-nodes glabrous. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs ciliate. Ligule a ciliolate membrane; 0.3 mm long. Leaf-blades flat, or involute; (16–)30–45 cm long; 2–3 mm wide. Leaf-blade venation prominent. Leaf-blade surface scaberulous; rough abaxially; glabrous, or pilose; sparsely hairy; hairy adaxially. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes. Peduncle 11–14 cm long; glabrous.

Racemes 1; single; straight, or arcuate; unilateral; 15–22 cm long. Rhachis glabrous on margins. Spikelet packing broadside to rhachis; crowded; regular; 2 -rowed.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 8–14 fertile florets; with diminished florets at the apex. Spikelets linear; laterally compressed; 10–12 mm long; 1–2 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.7 mm long. Floret callus pubescent. Floret callus hairs 0.5 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume oblong; 1.8–2 mm long; 0.75 length of upper glume; membranous; much thinner on margins; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex dentate; 2 -fid; acute. Upper glume oblong; 2.3–2.7 mm long; 0.8 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex dentate; 2 -fid; acute; mucronate, or awned; 1 -awned. Upper glume awn 0.5 mm long.

FLORETS Fertile lemma lanceolate, or oblong; 2.8 mm long; 0.8–1 mm wide; coriaceous; much thinner on margins; without keel; 3 -veined. Lemma lateral veins prominent. Lemma apex dentate; 6 -fid; with simple equal lobes; acuminate; awned; 3 -awned. Principal lemma awn from a sinus; 1.5–2.5 mm long overall. Lateral lemma awns arising on apex of lobes; 1.5–2.5 mm long; subequal to principal. Palea reflexed at apex, or separating from lemma above; 2.3–2.7 mm long. Palea keels scabrous. Palea surface scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 0.8 mm long.

DISTRIBUTION Asia-tropical: India.

NOTES Eragrostideae. Kabeer et al 2011.

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