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.

Oxytenanthera abyssinica

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms erect; 300–1000 cm long; 50–100 mm diam.; woody. Culm-internodes terete; with small lumen, or solid; distally pubescent (at first). Lateral branches dendroid. Branch complement many; in an irregular line; with 1 branch dominant. Culm-sheaths hispid; with dark brown hairs; without auricles. Culm-sheath blade linear; 1–2 cm long; acuminate. Leaves cauline. Leaf-sheath oral hairs setose. Ligule an eciliate membrane. Leaf-blade base broadly rounded; with a brief petiole-like connection to sheath. Leaf-blades deciduous at the ligule; lanceolate; 5–25 cm long; 10–30 mm wide; glaucous. Leaf-blade venation with obscure cross veins. Leaf-blade surface glabrous. Leaf-blade apex attenuate; hardened.

INFLORESCENCE Synflorescence bractiferous; stellate, or clustered at the nodes; in stellate clusters; 4–8 cm long; dense; with glumaceous subtending bracts; with axillary buds at base of spikelet; prophyllate below lateral spikelets; leafless between clusters.

FERTILE SPIKELETS Spikelets comprising 1(–2) fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed, or subterete; 15–40 mm long; breaking up at maturity; disarticulating above glumes but not between florets.

GLUMES Glumes several; 2–4 empty glumes; lower persistent, upper deciduous (with floret); similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume oblong to ovate; 5–8 mm long; 0.8 length of upper glume; coriaceous; without keels; 17–30 -veined. Lower glume surface hispidulous. Lower glume apex obtuse, or acute. Upper glume lanceolate; 12–20 mm long; coriaceous; without keels; 26–32 -veined. Upper glume lateral veins with cross-veins. Upper glume surface hispid. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 5–7 mm long.

FLORETS Fertile florets increasing in size upwards. Fertile lemma elliptic; 15–40 mm long; coriaceous; without keel; 26–32 -veined. Lemma lateral veins with cross-veins. Lemma surface hispid. Lemma margins convolute; covering most of palea. Lemma apex acute; awned; 1 -awned. Principal lemma awn pungent; 2–7 mm long overall. Palea lanceolate; tightly convolute around flower; scarious; 16–19 -veined; without keels, or 2-keeled but the uppermost without keels.

FLOWER Lodicules absent. Anthers 6; anther tip apiculate. Filaments united in a tube. Stigmas 3; papillose. Styles connate below. Ovary with a steeple-like appendage; glabrous.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, and south.

NOTES Bambuseae. FTEA.

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