Aristida macrantha

HABIT Perennial; caespitose. Basal innovations extravaginal and intravaginal. Culms erect; 40–80 cm long. Culm-internodes glaucous; smooth. Lateral branches lacking. Leaf-sheaths longer than adjacent culm internode; glabrous on surface. Leaf-sheath oral hairs pubescent. Ligule a fringe of hairs. Leaf-blades flat, or convolute; 10–70 cm long; 2–4 mm wide; stiff. Leaf-blade surface smooth, or scaberulous; rough adaxially. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; dense; 30 cm long. Primary panicle branches 2 -nate; 2 cm long. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 55 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 3–4 mm long; pubescent; hairy on the margins; acute.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 45 mm long; 0.8 length of upper glume; membranous; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex setaceously attenuate. Upper glume lanceolate; 55 mm long; membranous; 1 -veined. Upper glume primary vein smooth. Upper glume lateral veins absent. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma linear; subterete; 10–11 mm long; coriaceous; without keel; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn with 120 mm long limb. Lateral lemma awns 110 mm long; subequal to principal. Palea 2.5 mm long.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp; fusiform; without sulcus. Hilum linear.

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

NOTES Aristideae. Henrard 1995.

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