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.

Digitaria thyrsoidea

HABIT Perennial. Culms geniculately ascending; 100 cm long. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane. Leaf-blades 40–60 cm long; 9–13 mm wide. Leaf-blade surface glabrous; hairless except near base. Leaf-blade margins scaberulous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes numerous; 20–40; borne along a central axis; the lowest whorled; unilateral; 15–25 cm long. Central inflorescence axis 15–25 cm long. Rhachis angular; scaberulous on margins. Spikelet packing distant. Raceme-bases filiform; 10–20 mm long.

Spikelets solitary, or in pairs. Fertile spikelets pedicelled; 1–2 in the cluster. Pedicels unequal.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or oblong; dorsally compressed; 2–2.5 mm long; falling entire.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume orbicular; 0.1 mm long; 0.05 length of spikelet; hyaline. Lower glume apex obtuse. Upper glume oblong; 0.3–0.4 mm long; 0.15 length of spikelet; membranous; without keels. Upper glume surface pubescent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 1 length of spikelet; membranous; 7 -veined; pubescent; bearing hairs 0.1–0.35 mm long; acute. Fertile lemma oblong; 2–2.5 mm long; cartilaginous; much thinner on margins; dark brown; without keel; 3 -veined. Lemma lateral veins obscure. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

DISTRIBUTION Asia-tropical: Indo-China.

NOTES Paniceae. Lecomte 1993.

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