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.

Andropogon heterantherus

HABIT Perennial. Culms rambling; 60–120 cm long; wiry. Leaf-sheath auricles absent. Ligule an eciliate membrane. Leaf-blades lanceolate; tapering towards tip; 3–18 cm long; 3–8 mm wide. Leaf-blade apex acuminate.

INFLORESCENCE Synflorescence compound; linear. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear; 3–6 cm long.

Racemes 2(–3); paired; bilateral (as to sterile spikelets); 4–5 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes clavate. Rhachis internode tip transverse; crateriform; with simple rim.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels clavate; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; dorsally compressed; 5–5.5 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; laterally compressed; 5.5–6.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume linear; 1 length of spikelet; coriaceous; 2-keeled; keeled dorsally. Lower glume surface concave. Upper glume linear; chartaceous; 1-keeled. Upper glume muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 2 -veined. Fertile lemma oblong; hyaline; without keel. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 9–12 mm long overall; with twisted column. Column of lemma awn glabrous.

DISTRIBUTION Africa: east tropical.

NOTES Andropogoneae. FTEA.

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