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 trichozygus

HABIT Perennial; caespitose. Butt sheaths glossy. Basal innovations flabellate. Culms erect; (35–)50–110 cm long. Lateral branches lacking, or sparse. Leaves mostly basal. Leaf-sheaths keeled; glabrous on surface, or pilose. Ligule an eciliate membrane; 3–11 mm long; scarious; obtuse, or acute. Leaf-blades erect; straight; filiform; flat, or conduplicate, or convolute; 10–45 cm long; 0.6–3(–5.5) mm wide; stiff. Leaf-blade surface ribbed; glabrous; hairless throughout, or except near base. Leaf-blade margins scaberulous. Leaf-blade apex acute, or attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes (2–)3–8; paired, or digitate; 5–11 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis hairs 1–2 mm long. Rhachis internodes filiform; 2.5 mm long. Rhachis internode tip transverse; cupuliform; with simple rim.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; ciliate; with 1–2 mm long hairs.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; 3.6–6 mm long; as long as fertile. Companion sterile spikelet glumes chartaceous; glabrous; acute; muticous, or mucronate. 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; 4–6 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 lanceolate; 4–6 mm long; 1 length of spikelet; chartaceous; 2-keeled; keeled dorsally. Lower glume intercarinal veins absent. Lower glume surface concave; glabrous. Upper glume lanceolate; membranous; 1-keeled. Upper glume mucronate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline. Fertile lemma lanceolate; hyaline; without keel. Lemma apex lobed; 2 -fid; incised 0.25–0.33 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 8–10 mm long overall; with twisted column. Column of lemma awn glabrous.

FLOWER Anthers 3; 2 mm long.

DISTRIBUTION Africa: western Indian ocean.

NOTES Andropogoneae. Vorontsova 2013.

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