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.

Dignathia gracilis

HABIT Annual; caespitose. Culms erect; 20–50 cm long; wiry. Ligule a ciliate membrane. Leaf-blades 2–9 cm long; 2–4 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes numerous; borne along a central axis; in a multilateral false spike; oblong; sinuous; unilateral; 0.3–0.6 cm long; bearing few fertile spikelets; bearing (1–)2 fertile spikelets on each. Central inflorescence axis 3–8 cm long. Rhachis deciduous from axis; flattened; terminating in a sterile spikelet. Raceme-bases cuneate; 2 mm long; pilose; hairy on margins.

Spikelets solitary, or in pairs. Fertile spikelets sessile; 1–2 in the cluster; subequal.

STERILE SPIKELETS Apical sterile spikelets rudimentary; 1 in number.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets orbicular; laterally compressed; 2–3.5 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; gibbous; 2–2.5 mm long; 0.7–1 length of upper glume; coriaceous; 1-keeled; 1 -veined. Lower glume primary vein ciliolate. Lower glume lateral veins absent. Lower glume surface scabrous. Lower glume margins ciliolate. Lower glume apex acute. Upper glume orbicular; gibbous; 2–3.5 mm long; 1.1–1.7 length of adjacent fertile lemma; indurate; with hyaline margins; 1-keeled. Upper glume primary vein ciliolate. Upper glume surface scabrous. Upper glume margins ciliolate. Upper glume apex caudate.

FLORETS Fertile lemma ovate; 1.5–2 mm long; membranous; keeled; 3 -veined. Lemma midvein ciliolate. Lemma surface glabrous, or puberulous. Lemma apex acute; mucronate. Palea 2 -veined.

FLOWER Anthers 3; 1 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; dorsally compressed; plano-convex; 1.5 mm long.

DISTRIBUTION Africa: northeast tropical, east tropical, and southern tropical.

NOTES Cynodonteae. FTEA.

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