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.

Aulonemia xerophylla

HABIT Perennial; caespitose; clumped densely. Rhizomes short; pachymorph. Culms erect, or leaning; 100–300 cm long; 2–7 mm diam.; woody. Culm-internodes terete; hollow; 12–22 cm long; brown (pale); concolorous; distally pruinose. Culm-nodes without obvious supra-nodal ridge, or with distinct supra-nodal ridge; glabrous. Lateral branches dendroid. Bud complement 1. Branch complement one. Leaves 4–10 per branch. Leaf-sheaths keeled (above); glabrous on surface, or puberulous; outer margin glabrous. Leaf-sheath oral hairs setose; erect; 1–4(–6) mm long. Leaf-sheath auricles absent. Ligule a ciliolate membrane; 0.4–8 mm long; membranous. Collar with external ligule. Leaf-blade base asymmetrical; with a brief petiole-like connection to sheath; petiole 0.3–0.79 cm long; petiole pubescent. Leaf-blades reflexed; lanceolate; 10.2–22 cm long; 19–33 mm wide; coriaceous. Leaf-blade surface pubescent; hairy abaxially. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle. Peduncle glabrous.

Panicle open; ovate; effuse; 21.5–27.2 cm long; 8.8–20.2 cm wide. Primary panicle branches spreading.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2.5–17 mm long; glabrous.

FERTILE SPIKELETS Spikelets comprising 5–8 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 9–16 mm long; 2.5–4.5 mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; 5.2–6.6 mm long; membranous; without keels; 3–5 -veined. Lower glume surface glabrous, or puberulous. Lower glume margins ciliolate. Lower glume apex acute. Upper glume lanceolate; 6.8–8.2 mm long; membranous; without keels; 5–7 -veined. Upper glume surface glabrous, or puberulous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 5.8–7.5 mm long; chartaceous; purple; without keel; 5–9 -veined. Lemma surface puberulous. Lemma margins ciliate. Lemma apex acute, or apiculate. Palea 5.2–6.8 mm long; 2–4 -veined. Palea surface puberulous. Palea apex dentate; 2 -fid.

FLOWER Lodicules 3; lanceolate, or ovate; ciliate. Anthers 3; 2.4–4.5 mm long; yellow. Stigmas 2. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: Brazil.

NOTES Bambuseae. Vianin & Filg. 2013.

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