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 rosei

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; slender; 30–50 cm long; wiry. Leaf-sheaths keeled; glabrous on surface. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs; 0.4 mm long. Leaf-blades ascending, or spreading; involute; 2–5(–10) cm long; 1 mm wide. Leaf-blade surface scabrous; rough adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 5–15 cm long. Primary panicle branches appressed, or ascending. Panicle branches flexuous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 6–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 0.5 mm long; pubescent; obtuse.

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma. Lower glume linear; 5 mm long; 0.7–0.8 length of upper glume; membranous; 1 -veined. Lower glume primary vein smooth. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume linear; 6–7 mm long; membranous; 1 -veined. Upper glume primary vein smooth. Upper glume lateral veins absent. Upper glume apex acuminate; mucronate.

FLORETS Fertile lemma linear; subterete; 6 mm long; coriaceous; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn with 10 mm long limb. Lateral lemma awns gyrate; 10 mm long; subequal to principal.

FLOWER Anthers 3.

DISTRIBUTION South America: Caribbean.

NOTES Aristideae. N Amer Fl 1994.

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