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 subsulcata

HABIT Perennial; caespitose. Rhizomes short. Basal innovations intravaginal. Culms geniculately ascending, or decumbent; 50–70 cm long; rooting from lower nodes. Culm-internodes 2–3 cm long. Lateral branches sparse. Leaf-sheaths pubescent; with tubercle-based hairs. Ligule an eciliate membrane. Leaf-blades convolute; 4–10 cm long; 3–4 mm wide. Leaf-blade surface pilose; sparsely hairy; with tubercle-based hairs.

INFLORESCENCE Inflorescence composed of racemes. Peduncle 10–20 cm long.

Racemes 2; paired; unilateral; 10–16 cm long. Rhachis angular; 0.6–0.7 mm wide; scaberulous on margins.

Spikelets in threes. Fertile spikelets pedicelled; 3 in the cluster. Pedicels unequal; 1–5 mm long; scaberulous; pubescent; hairy at tip; tip cupuliform.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 3–3.5 mm long; 1 mm wide; falling entire.

GLUMES Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume lanceolate; 0.25 length of spikelet; membranous; without keels; 3–5 -veined. Upper glume surface pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1 length of spikelet; membranous; 5 -veined; with thickened veins; pubescent; hairy between veins; acuminate. Fertile lemma elliptic; 3–3.5 mm long; cartilaginous; much thinner on margins; without keel; 3 -veined. Lemma lateral veins obscure. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

DISTRIBUTION Africa: west-central tropical.

NOTES Paniceae. Van der Veken 1993.

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