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 gyrans

HABIT Perennial; caespitose. Culms erect; slender; 40–70 cm long. Culm-internodes distally glabrous. Leaf-sheaths glabrous on surface. Ligule a fringe of hairs. Leaf-blades involute; 10–15 cm long; 1 mm wide. Leaf-blade surface scabrous; rough adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 15–30 cm long. Primary panicle branches appressed; bearing 1–3(–6) fertile spikelets on each lower branch.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 10–11 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 1.5 mm long; pubescent; pungent.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume linear; 7–8 mm long; 0.7–0.8 length of upper glume; membranous; 2 -veined. Lower glume primary vein smooth. Lower glume apex setaceously attenuate. Upper glume linear; 10–11 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; 6 mm long; coriaceous; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex scabrous; with a short cylindrical neck; with this appendage 0.5 mm long; awned; 3 -awned. Principal lemma awn spreading; with 10–15 mm long limb. Lateral lemma awns gyrate; 10–15 mm long; subequal to principal.

FLOWER Anthers 3.

DISTRIBUTION North America: southeast USA.

NOTES Aristideae. N Amer Fl 1994.

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