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 diffusa

HABIT Perennial. Culms decumbent; slender; 10–40 cm long; rooting from lower nodes. Culm-nodes glabrous, or pubescent. Lateral branches ample. Leaf-sheaths 2–5 cm long; striately veined; glabrous on surface, or pilose. Ligule an eciliate membrane; 1–2 mm long; truncate. Leaf-blades 1.5–8 cm long; 0.75–3 mm wide. Leaf-blade midrib indistinct, or evident. Leaf-blade surface glabrous, or pubescent. Leaf-blade margins entire, or undulate. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–7; borne along a central axis; spreading; unilateral; 3–7 cm long. Central inflorescence axis 3–5 cm long. Rhachis angular. Spikelet packing distant.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels tip cupuliform.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; acute; 1.5–1.75 mm long; 0.75 mm wide; falling entire.

GLUMES Glumes reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.1–0.25 length of spikelet; membranous; 0 -veined. Lower glume lateral veins absent. Lower glume apex truncate, or obtuse. Upper glume elliptic; 1 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 5–7 -veined; pubescent; hairy between veins, or between veins but central interspaces glabrous; acute. Fertile lemma elliptic; 1.5–1.75 mm long; cartilaginous; much thinner on margins; dark brown; without keel. Lemma margins flat; covering most of palea. Lemma apex apiculate. Palea cartilaginous.

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Fl NSW 1993.

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