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.

Trachypogon spicatus

HABIT Perennial; caespitose. Culms 30–200 cm long. Culm-nodes bearded. Ligule an eciliate membrane. Leaf-blades filiform, or linear; flat, or convolute; 15–40 cm long; 1–7 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1(–3); single, or paired, or digitate; straight, or flexuous; 4–30 cm long. Rhachis tough; subterete. Rhachis internodes linear; 4–5 mm long. Rhachis internode tip oblique; flat.

Spikelets in pairs. Fertile spikelets pedicelled; 1 in the cluster; on longer pedicels than sterile. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; tip oblique.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; oblong; dorsally compressed; 8–13 mm long; as long as fertile; persistent. Companion sterile spikelet glumes chartaceous; winged on margins (narrowly); distinctly veined; emarginate, or truncate, or obtuse. Companion sterile spikelet lemmas 2; enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 8–13 mm long; falling entire. Spikelet callus linear; 1–3 mm long; bearded; base pungent; attached obliquely. Spikelet callus hairs white.

GLUMES Glumes dissimilar; firmer than fertile lemma; dull, or shiny. Lower glume oblong; 1 length of spikelet; coriaceous; grey to dark brown; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume surface glabrous, or pubescent, or villous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 0.9 length of spikelet; hyaline; 2 -veined; ciliate on margins; obtuse. Fertile lemma linear; 0.5 mm long; hyaline; without keel; 3 -veined. Lemma apex entire; acute; awned; 1 -awned. Principal lemma awn apical; geniculate; 40–100 mm long overall; with twisted column. Column of lemma awn plumose. Palea absent or minute.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, south, and western Indian ocean. North America: southwest USA, south-central USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Andropogoneae. FTEA.

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