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 monocladus

HABIT Perennial; caespitose. Culms 170–250 cm long; 9–10 -noded. Culm-internodes distally glabrous. Leaf-sheaths mostly shorter than adjacent culm internode; hirsute. Ligule a ciliolate membrane; 1–1.2 mm long; truncate. Leaf-blades 22–70 cm long; 5–7 mm wide. Leaf-blade surface glabrous, or hirsute; hairy on both sides. Leaf-blade margins scabrous. Leaf-blade apex abruptly acute, or acute.

INFLORESCENCE Synflorescence compound; linear. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear; 3.5–7 cm long. Peduncle 1.5–6.5 cm long.

Racemes 1; single; 2.5–5 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear; 2.2–3.5 mm long. Rhachis internode tip transverse; cupuliform; with simple rim.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; 2.2–3.5 mm long; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; 3–5.5 mm long; shorter than fertile, or as long as fertile, or longer than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; glabrous; acute; muticous. Companion sterile spikelet lemmas enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4.5–5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; 2-keeled; keeled laterally; 2 -veined. Lower glume primary vein scaberulous. Lower glume intercarinal veins absent. Lower glume surface concave. Lower glume apex erose, or dentate; 2 -fid. Upper glume linear; 3.5–4 mm long; coriaceous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume margins ciliate. Upper glume apex acuminate; muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 3–4 mm long; hyaline; 2–3 -veined; ciliate on margins; fringed above. Fertile lemma lanceolate; 3–3.5 mm long; hyaline; without keel; 1–3 -veined. Lemma apex lobed; 2 -fid; incised 0.2–0.33 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 8–9 mm long overall; with a straight or slightly twisted column. Column of lemma awn glabrous. Palea 0.8–1.2 mm long; hyaline; 0 -veined; without keels. Palea apex erose.

FLOWER Lodicules 2; 0.8 mm long. Anthers 3; 0.6–1 mm long; yellow.

FRUIT Caryopsis 2–5 mm long.

DISTRIBUTION South America: Brazil.

NOTES Andropogoneae. Zanin & Longhi-Wag 2005.

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