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.

Urelytrum digitatum

HABIT Perennial; caespitose. Culms erect; 100–200 cm long. Leaf-sheaths pubescent. Ligule an eciliate membrane; 1–3(–5) mm long. Leaf-blades 10–40 cm long; 4–10 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes (1–)3–4(–10); digitate; smoothly terete; 15–30 cm long. Central inflorescence axis 2–7(–12) cm long. Rhachis fragile at the nodes; semiterete; glabrous on surface. Rhachis internodes cuneate. Rhachis internode tip oblique; crateriform; with scarious rim. Raceme-bases linear; 10–15 mm long.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels cuneate; glabrous; tip cupuliform.

STERILE SPIKELETS Companion sterile spikelets well-developed; elliptic; 2–7 mm long; shorter than fertile; persistent. Companion sterile spikelet glumes coriaceous; awned; one glume awned; with 20–35(–50) mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 6.5–11 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus oblong; 0.5 mm long; pubescent; base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; coriaceous; without keels; keel-less except near apex. Lower glume surface spinose; rough on flanks. Lower glume apex entire, or dentate; 2 -fid; acute. Upper glume ovate; chartaceous; 1-keeled; 3 -veined.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret oblong; hyaline; 2 -veined. Fertile lemma lanceolate; hyaline; without keel; 3 -veined. Lemma apex acute. Palea hyaline.

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

NOTES Andropogoneae. FTEA.

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