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 thorelii

HABIT Perennial; caespitose. Culms erect; 30–40 cm long. Culm-internodes distally glabrous. Culm-nodes pubescent. Leaves mostly basal. Leaf-sheaths striately veined; smooth; glabrous on surface. Ligule a ciliolate membrane. Leaf-blades 4–6 cm long; 1.5–2 mm wide. Leaf-blade midrib scarcely raised beneath. Leaf-blade venation indistinct. Leaf-blade surface smooth; glabrous.

INFLORESCENCE Synflorescence compound; scanty. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear, or lanceolate; 7–10 cm long.

Racemes 2; paired; 3–3.5 cm long. Rhachis fragile at the nodes; villous on margins. Rhachis hairs 4–5 mm long. Rhachis internodes filiform; 4 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; 4.5 mm long; villous; with 4–5 mm long hairs.

STERILE SPIKELETS Companion sterile spikelets represented by single glumes; linear; 2–3 mm long; shorter than fertile. Companion sterile spikelet glumes chartaceous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear, or lanceolate; dorsally compressed; 5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base obtuse; inserted. Spikelet callus hairs 2.5 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume linear, or lanceolate; 1 length of spikelet; membranous; 2-keeled; keeled laterally; 5 -veined. Lower glume surface flat. Lower glume apex acute. Upper glume linear; 5 mm long; membranous; 1-keeled. Upper glume apex acute; muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 4.5 mm long; hyaline; 2 -veined. Fertile lemma oblong; 1.5–1.8 mm long; hyaline; without keel. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 12 mm long overall; with twisted column. Column of lemma awn glabrous.

DISTRIBUTION Asia-tropical: Indo-China.

NOTES Andropogoneae. Fl Indo-Chine 1997.

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