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.

Themeda yunnanensis

HABIT Perennial. Culms erect; 50–100 cm long. Culm-internodes brown; distally glabrous. Leaf-sheaths mostly shorter than adjacent culm internode; keeled; glabrous on surface. Ligule a ciliolate membrane. Leaf-blades 15–30 cm long; 3–5 mm wide. Leaf-blade venation indistinct. Leaf-blade surface glabrous. Leaf-blade margins scabrous. Leaf-blade apex attenuate.

INFLORESCENCE Synflorescence compound; fasciculate; lax. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole ovate; 3–5 cm long; scarious; without tubercles; glabrous. Peduncle 1–2 cm long; glabrous.

Racemes 1; single; cuneate; 2.5–3.5 cm long; bearing few fertile spikelets; bearing 2 fertile spikelets on each. Rhachis fragile at the nodes.

Spikelets in pairs, or in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster, or 2 in the cluster. Pedicels oblong; tip oblique.

STERILE SPIKELETS Basal sterile spikelets well-developed; 4 in number; forming an involucre about the fertile; with normal internodes; subsessile; male; lanceolate; 15 mm long; larger than fertile. Basal sterile spikelet glumes herbaceous; glabrous; lower glume muticous.

Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; 30 mm long; longer than fertile; separately deciduous. Companion sterile spikelet callus linear; truncate. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; subterete; 10 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; bearded; base pungent; attached obliquely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; without keels. Lower glume surface pubescent; hairy below. Lower glume hairs yellow. Lower glume apex obtuse. Upper glume oblong; coriaceous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline. Fertile lemma linear; hyaline; without keel; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate, or bigeniculate; 30–60 mm long overall; with twisted column. Column of lemma awn hispidulous. Palea absent or minute.

FLOWER Anthers 3; 5 mm long.

DISTRIBUTION Asia-temperate: China.

NOTES Andropogoneae. Chen & Zhuang 1996.

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