Aristida effusa

HABIT Annual; caespitose. Culms erect; slender; 45–90 cm long. Culm-internodes distally glabrous. Culm-nodes glabrous. Lateral branches ample. Ligule a fringe of hairs. Leaf-blades flat; 15–30 cm long; 2–3 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; effuse; 20–30 cm long; 15 cm wide; with spikelets clustered towards branch tips. Primary panicle branches spreading. Panicle branches flexuous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 10–11.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; bearded; obtuse.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; 6–8.5 mm long; 0.66–1.1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume surface scabrous; rough above. Lower glume apex acute, or acuminate. Upper glume lanceolate; 5.5–8 mm long; 0.66 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein smooth. Upper glume lateral veins absent. Upper glume apex truncate, or obtuse.

FLORETS Fertile lemma linear; subterete; 9–11.5 mm long; coriaceous; keeled; 3 -veined. Lemma surface scabrous; rough above. Lemma margins convolute; covering most of palea. Lemma apex acute; awned; 3 -awned. Principal lemma awn with 16 mm long limb; persistent. Lateral lemma awns 13 mm long; shorter than principal. Palea without keels.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp; linear.

DISTRIBUTION Africa: south.

NOTES Aristideae. De Winter 1993.

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