GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Andropogon eucomus

HABIT Perennial; caespitose. Culms erect; 30–200 cm long. Lateral branches sparse; arising from upper culm. Leaf-sheaths without keel, or keeled. Leaf-sheath oral hairs lacking, or ciliate. Ligule a ciliolate membrane; 0.5–1 mm long; membranous; truncate. Leaf-blades straight, or curved; flat, or conduplicate; 4–25 cm long; 1–3.5 mm wide; red. Leaf-blade surface glabrous; hairless throughout, or except near base. Leaf-blade margins smooth, or scaberulous. Leaf-blade apex acute.

INFLORESCENCE Synflorescence simple, or compound; scanty, or linear; open. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear; 5–9 cm long.

Racemes 3–6; digitate; sinuous; 2–5 cm long. Rhachis fragile at the nodes; glabrous on surface, or plumose on surface; plumose on margins. Rhachis hairs 2–16 mm long. Rhachis internodes filiform; 4–5 mm long. Rhachis internode tip transverse; cupuliform; with simple rim.

Spikelets ascending; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; curved; 4–5 mm long; plumose; with 4–12 mm long hairs.

STERILE SPIKELETS Companion sterile spikelets represented by barren pedicels, or rudimentary. Companion sterile spikelet glumes glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear, or lanceolate; dorsally compressed; 2–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus brief; pilose; base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume linear, or lanceolate; 2–7 mm long; 1 length of spikelet; membranous; 2-keeled; keeled laterally. Lower glume intercarinal veins absent. Lower glume surface concave; glabrous. Upper glume linear, or lanceolate; membranous; 1-keeled. Upper glume muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 0–2 -veined; without midvein; without lateral veins, or obscurely veined; ciliate on margins. Fertile lemma lanceolate, or oblong; hyaline; without keel. Lemma margins ciliolate. Lemma apex lobed; 2 -fid; incised 0.25–0.5 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; flexuous; 12–18 mm long overall; without a column, or with a straight or slightly twisted column, or with twisted column. Palea present, or absent or minute; oblong.

FLOWER Anthers 3; 1.5 mm long.

DISTRIBUTION Africa: west-central tropical, northeast tropical, east tropical, southern tropical, south, and western Indian ocean.

NOTES Andropogoneae. FTEA 1997.

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