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.

Exotheca

HABIT Perennial. Culms 30–200 cm long. Leaf-sheath auricles erect. Ligule an eciliate membrane.

INFLORESCENCE Synflorescence compound; scanty. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear; scarious.

Racemes paired; end to end; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis fragile at the nodes. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases filiform; unequal (the longer measured).

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform.

STERILE SPIKELETS Basal sterile spikelets well-developed; forming an involucre about the fertile.

Companion sterile spikelets well-developed; deciduous with the fertile. Companion sterile spikelet glumes muticous, or awned.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 12–15 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; pilose; base pungent; attached obliquely.

GLUMES Glumes exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; coriaceous; without keels; 9 -veined. Lower glume lateral veins ribbed. Lower glume surface without pits; pubescent. Lower glume apex dentate; 2 -fid. Upper glume lanceolate; coriaceous; without keels; 3 -veined. Upper glume surface glabrous, or pubescent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 2 -veined; obtuse. Fertile lemma linear; hyaline; without keel; wingless; 3 -veined. Lemma surface unwrinkled; without grooves. Lemma margins ciliolate. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate. Column of lemma awn pubescent. Palea hyaline. Palea keels ciliate.

DISTRIBUTION Africa, or Tropical Asia.

Please cite this publication as detailed in How to Cite Version: 27th January 2014.