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 boninensis

HABIT Perennial; caespitose; clumped densely. Rhizomes short. Culms 10–30 cm long; 0.3–0.6 mm diam.; 1–2 -noded. Culm-internodes smooth. Leaves mostly basal. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Leaf-blades conduplicate; 5–12 cm long; 1–1.5 mm wide; stiff. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; effuse; 5–8 cm long; 2–4 cm wide. Primary panicle branches ascending; 1–2 -nate. Panicle axis smooth. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 10–12 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 1.3–1.5 mm long; pubescent; acute.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 6–9 mm long; 0.66 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 9–12 mm long; 1.5–1.7 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma linear; subterete; 6–7 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 40–60 mm long limb; with twisted column. Column of lemma awn 6–7 mm long. Lateral lemma awns 15–20 mm long; shorter than principal.

FLOWER Anthers 3.

DISTRIBUTION Asia-temperate: eastern Asia.

NOTES Aristideae. Gr Japan 1997.

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