Aristida cognata

HABIT Perennial; caespitose. Culms geniculately ascending; 20–40 cm long. Lateral branches sparse; arising from lower culm. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs lacking, or ciliate. Ligule a fringe of hairs. Leaf-blades involute; 5–15 cm long; 1 mm wide. Leaf-blade surface scabrous; rough adaxially; pilose; sparsely hairy; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; 5–15 cm long. Primary panicle branches ascending; 1–2 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 0.5 mm long; pubescent; acute.

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma. Lower glume linear; 4–5 mm long; 0.7–0.8 length of upper glume; membranous; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume linear; 5–7 mm long; membranous; 1 -veined. Upper glume primary vein smooth. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma linear; subterete; 6–7 mm long; coriaceous; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex with a short cylindrical neck; with this appendage 1 mm long; awned; 3 -awned. Principal lemma awn 3-branched; with 10–15 mm long limb. Lateral lemma awns spreading less than principal; 10–15 mm long; subequal to principal.

FLOWER Anthers 3.

DISTRIBUTION South America: Caribbean and northern South America.

NOTES Aristideae. N Amer Fl 1994.

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