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.

Elionurus tristis

HABIT Perennial; caespitose. Culms erect; slender; 15–60 cm long. Culm-nodes black; glabrous. Lateral branches lacking, or sparse. Leaves mostly basal. Ligule a fringe of hairs. Leaf-blades involute; 5–25 cm long; 1–3 mm wide. Leaf-blade surface glabrous, or pilose.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; straight, or arcuate; 3–9 cm long; 2–3 mm wide. Rhachis fragile at the nodes; subterete; pubescent on surface, or pilose on surface. Rhachis internodes linear; 2–3.5 mm long. Rhachis internode tip oblique; flat; with simple rim.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; flattened; pubescent, or ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; dorsally compressed; 3.5–5.5 mm long; shorter than fertile; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; glabrous; ciliolate on margins; dentate; 2 -fid. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4–6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; pubescent; base obtuse; attached obliquely.

GLUMES Glumes dissimilar; reaching apex of florets; firmer than fertile lemma. Lower glume ovate; 1 length of spikelet; chartaceous; 2-keeled. Lower glume primary vein ciliolate. Lower glume surface convex, or flat; glabrous. Lower glume apex dentate; 2 -fid. Upper glume lanceolate; 1-keeled. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; hyaline. Fertile lemma oblong; hyaline; without keel; 3 -veined. Palea absent or minute.

FLOWER Anthers 3.

DISTRIBUTION Africa: western Indian ocean.

NOTES Andropogoneae. Bosser 1994.

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