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.

Bouteloua juncea

HABIT Perennial; caespitose. Stolons absent, or present. Culms slender; 5–30 cm long. Leaf-sheaths pilose. Ligule a ciliate membrane; 0.5 mm long. Leaf-blades curved; involute; 1–4 cm long; 1–2 mm wide; stiff.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 8–20; borne along a central axis; erect, or ascending; unilateral; 0.7 cm long; bearing 1 spikelet; bearing 1 fertile spikelets on each. Central inflorescence axis 1–5 cm long; tip subulate. Rhachis deciduous from axis; subterete; terminating in a barren extension; extension subulate; extension 1–2 mm long. Spikelet packing broadside to rhachis.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 2.8–5 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume lanceolate; 1 mm long; 0.3–0.5 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein ciliate. Lower glume lateral veins absent. Lower glume apex acute, or acuminate. Upper glume lanceolate; 1.8–3 mm long; 0.6–0.7 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein ciliate. Upper glume lateral veins absent. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma lanceolate; 2.8–5 mm long; membranous; keeled; 3 -veined. Lemma surface scabrous; glabrous, or pubescent. Lemma apex dentate; 3 -fid; acute; mucronate; 3 -awned (mucros). Palea apex with excurrent keel veins. Rhachilla extension glabrous. Apical sterile florets 1 in number; barren; linear; 4 mm long. Apical sterile lemmas awned; 3 -awned. Apical sterile lemma awns equal; 6–9 mm long.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp; 1.5 mm long.

DISTRIBUTION South America: Caribbean.

NOTES Cynodonteae. Gould.

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