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 brevisubulata

HABIT Annual, or perennial; short-lived; caespitose; clumped loosely. Culms erect, or geniculately ascending; 30–60 cm long. Culm-internodes distally glabrous. Culm-nodes purple; glabrous. Lateral branches ample. Leaf-sheaths loose, or inflated; glabrous on surface. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Leaf-blades involute; 3–20 cm long; 1–2 mm wide. Leaf-blade surface scabrous; rough adaxially; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 5–15 cm long. Primary panicle branches 2–3 -nate; indistinct the panicle almost racemose, or simple; bearing 1–2 fertile spikelets on each lower branch. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 20 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 2 mm long; pubescent; acute.

GLUMES Glumes dissimilar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 10 mm long; 0.5 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute; mucronate. Upper glume linear; 20 mm long; 3.3 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex dentate; 2 -fid; mucronate.

FLORETS Fertile lemma linear; subterete; 6 mm long; coriaceous; without keel; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn 3-branched; with 50–55 mm long limb; with twisted column; deciduous; abscissing from top of lemma. Column of lemma awn 12–25 mm long. Lateral lemma awns 50–55 mm long; subequal to principal. Palea 1.5 mm long; 0.25 length of lemma.

FLOWER Lodicules 2; oblong; 2 mm long; ciliate; hairy across the apex; truncate. Anthers 3; 3 mm long.

FRUIT Caryopsis with adherent pericarp; linear; 4 mm long. Embryo 0.25 length of caryopsis. Hilum linear; 1 length of caryopsis.

DISTRIBUTION Africa: north and west tropical.

NOTES Aristideae. Fl Afr N 1994.

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