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.

Aristida divulsa

HABIT Perennial; caespitose. Culms erect; 30–80 cm long; 3–4 -noded. Culm-internodes terete; smooth, or scaberulous. Culm-nodes swollen. Lateral branches lacking, or sparse; arising from mid culm. Leaf-sheaths mostly shorter than adjacent culm internode; smooth, or scaberulous; glabrous on surface; outer margin hairy. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Leaf-blades flat, or convolute; 10–30 cm long; 1–2.5 mm wide. Leaf-blade surface pubescent; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 15–20 cm long; contracted about primary branches. Primary panicle branches 1 -nate; bearing spikelets almost to the base.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pilose; obtuse.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 7 mm long; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex attenuate. Upper glume lanceolate; 6 mm long; membranous; 1-keeled; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume apex dentate; 2 -fid; mucronate.

FLORETS Fertile lemma oblong; subterete; 3 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 12 mm long limb; with twisted column; deciduous; abscissing from top of column. Column of lemma awn 1.5–3 mm long. Lateral lemma awns 12 mm long; subequal to 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.