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.

Aristida villosa

HABIT Annual. Culms erect, or geniculately ascending; 15–35 cm long; 3–6 -noded. Culm-internodes terete; distally pubescent. Culm-nodes flush with internodes; glabrous. Lateral branches lacking, or sparse. Leaf-sheaths mostly shorter than adjacent culm internode; hirsute. Leaf-sheath oral hairs bearded. Ligule a fringe of hairs. Collar glabrous, or pubescent. Leaf-blades flat, or convolute; 5–12 cm long; 2.5–3 mm wide; glaucous. Leaf-blade surface scaberulous; rough on both sides; pubescent; hairy on both sides. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; 4–7 cm long. Primary panicle branches 1 -nate. Panicle axis pubescent.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 0.5 mm long; pilose; obtuse.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 4 mm long; membranous; 1-keeled; 3 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins obscure. Lower glume surface asperulous; rough on veins; glabrous, or puberulous. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 2 mm long. Upper glume lanceolate; 6 mm long; membranous; 1-keeled; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume surface puberulous. Upper glume apex dentate; 2 -fid; awned; 1 -awned. Upper glume awn 2–3 mm long.

FLORETS Fertile lemma ovate; subterete; 4 mm long; coriaceous; without keel; 3 -veined. Lemma surface scaberulous; rough above. Lemma margins convolute; covering most of palea. Lemma apex acute; awned; 3 -awned. Principal lemma awn 3-branched; with 9–15 mm long limb; with a straight or slightly twisted column; deciduous; abscissing from top of column. Column of lemma awn 1 mm long. Lateral lemma awns 5–6 mm long; shorter than principal.

DISTRIBUTION South America: western South America.

NOTES Aristideae. Henrard 1999.

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