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.

Agenium villosum

HABIT Perennial; caespitose; clumped densely. Culms erect; 15–50 cm long. Ligule an eciliate membrane. Leaf-blades 10–25 cm long; 2–4 mm wide. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes; terminal.

Racemes 2–7; paired, or digitate; drooping; 3–4 cm long. Central inflorescence axis 0.5–1 cm long. Rhachis fragile at the nodes; flattened; ciliate on margins. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases filiform; 2–10 mm long; glabrous.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; flattened; 1–2 mm long; villous.

STERILE SPIKELETS Basal sterile spikelets well-developed; 4–9 in number; male; lanceolate; 5–6 mm long; equalling fertile. Basal sterile spikelet glumes herbaceous; villous.

Companion sterile spikelets well-developed; male; elliptic; dorsally compressed; 5–6 mm long; as long as fertile; separately deciduous. Companion sterile spikelet callus cuneate; 0.5 mm long; obtuse. Companion sterile spikelet glumes herbaceous; tuberculate; villous; acute. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 5–7.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 1 mm long; bearded; base pungent; attached obliquely. Spikelet callus hairs red.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 5–7.5 mm long; 1 length of spikelet; coriaceous; without keels; 8 -veined. Lower glume surface with a longitudinal median groove; pilose. Lower glume apex obtuse. Upper glume lanceolate; coriaceous; without keels. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 3–4 mm long; hyaline; 2 -veined; truncate. Fertile lemma linear; 5 mm long; cartilaginous; without keel; 1 -veined. Lemma apex entire; acute; awned; 1 -awned. Principal lemma awn geniculate; 30–40 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FRUIT Disseminule comprising a spikelet.

DISTRIBUTION South America: western South America, Brazil, and southern South America.

NOTES Andropogoneae. WDC.

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