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 flabellata

HABIT Annual; caespitose; clumped densely. Basal innovations intravaginal; flabellate. Culms erect; 40–50 cm long; 1–2 -noded. Culm-internodes terete; distally glabrous. Culm-nodes glabrous. Lateral branches sparse; arising from lower culm. Leaf-sheaths longer than adjacent culm internode; striately veined; smooth, or scaberulous. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Collar glabrous. Leaf-blades conduplicate, or convolute; 3.5–15 cm long; 1.5–2 mm wide. Leaf-blade surface scabrous; rough on both sides. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; continuous, or interrupted; 17–20 cm long. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 5–9 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 0.5–0.75 mm long; pubescent; obtuse.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 4–7 mm long; 0.75 length of upper glume; membranous; 1 -veined. Lower glume primary vein ciliolate. Lower glume lateral veins absent. Lower glume apex mucronate. Upper glume lanceolate; 5–9 mm long; 1 length of adjacent fertile lemma; membranous; 1 -veined. Upper glume primary vein smooth, or scaberulous. Upper glume lateral veins absent. Upper glume apex dentate; 2 -fid; mucronate.

FLORETS Fertile lemma linear; subterete; 5.5–8.5 mm long; coriaceous; without keel; 3 -veined. Lemma midvein scabrous. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn with 8–15 mm long limb. Lateral lemma awns 6–13 mm long; subequal to principal, or shorter than principal. Palea 1 mm long; 0.1–0.2 length of lemma; hyaline; 0 -veined.

FLOWER Lodicules 2. Anthers 3.

FRUIT Caryopsis with adherent pericarp; 7–7.5 mm long; light brown.

DISTRIBUTION South America: southern South America.

NOTES Aristideae. Caro 1997.

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