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 unica

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; robust; 100–250 cm long; 4–10 mm diam.; 6–8 -noded. Culm-internodes terete; distally glabrous. Leaf-sheaths loose; keeled; pilose; with tubercle-based hairs. Ligule an eciliate membrane; 2–7 mm long; obtuse. Leaf-blades 30–60 cm long; 4–10 mm wide. Leaf-blade midrib prominent beneath. Leaf-blade surface glabrous; hairless except near base. Leaf-blade apex acuminate.

INFLORESCENCE Synflorescence compound; fasciculate; 100–150 cm long; open; with principal spatheoles embracing a compact fascicle of racemes, each subtended by a subsidiary bract (4–6 racemes). Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole lanceolate; 4–9 cm long; scarious; without tubercles; pilose.

Racemes 1; single; cuneate; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis fragile at the nodes.

Spikelets in threes (basal paired). Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels oblong; 1 mm long.

STERILE SPIKELETS Basal sterile spikelets well-developed; 4 in number; forming an involucre about the fertile; with normal internodes; subsessile; male; lanceolate; 25–40 mm long; larger than fertile. Basal sterile spikelet glumes tuberculate; setose; attenuate; lower glume muticous.

Companion sterile spikelets well-developed; male; lanceolate; 25–40 mm long; longer than fertile; separately deciduous. Companion sterile spikelet callus linear; 3–5 mm long. Companion sterile spikelet glumes herbaceous; pilose; attenuate.

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 oblong; pubescent; attached obliquely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume ovate; 1 length of spikelet; coriaceous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume surface hirsute. Upper glume oblong; coriaceous; 3 -veined.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 0 -veined; without midvein; without lateral veins. Fertile lemma linear; hyaline; without keel; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate; 20–40 mm long overall; with twisted column. Column of lemma awn pubescent. Palea absent or minute.

FLOWER Lodicules 1; cuneate.

DISTRIBUTION Asia-temperate: China.

NOTES Andropogoneae. Chen 2001.

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