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 hydrophila

HABIT Annual; caespitose. Culms erect; 25 cm long; 4–7 -noded. Culm-nodes glabrous. Lateral branches lacking. Ligule an eciliate membrane; 3–4 mm long. Leaf-blades linear, or lanceolate; 5–15 cm long; 4–8 mm wide; flaccid. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 6–9; digitate; unilateral; 3–5 cm long. Central inflorescence axis 1–3 cm long. Rhachis angular; scaberulous on margins.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels angular; unequal; 0.5–4 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 2.4–2.8 mm long; 1 mm wide; falling entire.

GLUMES Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume ovate, or orbicular; 0.6–0.7 mm long; 0.25 length of spikelet; hyaline; without keels; 1–3 -veined. Upper glume lateral veins absent, or obscure. Upper glume surface glabrous. Upper glume apex erose; obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1 length of spikelet; membranous; 7(–9) -veined; with equidistant veins; glabrous; acute. Fertile lemma elliptic; 2 mm long; cartilaginous; much thinner on margins; dark brown; shiny; without keel; 3 -veined. Lemma lateral veins obscure. Lemma surface granulose. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

FRUIT Caryopsis 0.8 mm long.

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.