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

HABIT Annual (1), or perennial (6). Culms erect; robust (1/1); 50–145.7–400 cm long. Leaf-sheath auricles absent (5), or erect (3). Ligule an eciliate membrane (6), or a ciliolate membrane (1). Leaf-blades stiff (2), or firm (5).

INFLORESCENCE Inflorescence composed of racemes.

Racemes single (4), or paired (3), or digitate (3), or borne along a central axis (1). Rhachis fragile at the nodes; semiterete. Rhachis internodes linear (1), or oblong (3), or cuneate (3). Rhachis internode tip oblique; crateriform. Raceme-bases brief (3), or linear (4).

Spikelets sunken (1/1); in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear (1), or oblong (3), or cuneate (3); tip cupuliform.

STERILE SPIKELETS Companion sterile spikelets rudimentary (3), or well-developed (5); persistent. Companion sterile spikelet glumes muticous (2), or awned.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (3), or elliptic (1), or oblong (5); dorsally compressed; 5–7.871–11 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus brief (1), or square (1), or oblong (5); pubescent; base truncate (1), or obtuse (6); inserted.

GLUMES Glumes exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate (1), or elliptic (6); coriaceous; without keels; 5 -veined (3/3). Lower glume surface convex, or flat (2); smooth (4), or spinose (4), or muricate (2); without pits; glabrous, or pubescent (2). Lower glume apex entire, or dentate (1); 2 -fid (1/1); acute. Upper glume ovate; membranous (1), or chartaceous (4), or scarious (1), or coriaceous (1); 1-keeled; 3 -veined. Upper glume primary vein eciliate (5), or ciliolate (1), or ciliate (1). Upper glume apex acute (1/1).

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret linear (1), or lanceolate (2), or oblong (4), or ovate (1); hyaline; 2 -veined; obtuse (1/1). Fertile lemma lanceolate (4), or oblong (3), or ovate (3); hyaline; without keel; wingless; 3 -veined. Lemma surface unwrinkled; without grooves. Lemma margins eciliate (4), or ciliolate (3). Lemma apex obtuse (1), or acute (6). Palea hyaline; 2 -veined (1/1).

FLOWER Anthers 3 (3/3).

DISTRIBUTION Africa.

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