GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Setaria geminata

HABIT Perennial; mat forming. Rhizomes elongated; spongy. Culms prostrate; 10–180 cm long; spongy; rooting from lower nodes. Ligule a fringe of hairs. Leaf-blades flat, or conduplicate; 5–35 cm long; 2–13 mm wide. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes borne along a central axis; appressed; unilateral; 0.5–4 cm long. Central inflorescence axis 5–30 cm long; flattened. Rhachis narrowly winged; with sharp-edged midrib; angular; 0.5–1 mm wide; terminating in a barren extension; extension inconspicuous. Spikelet packing abaxial; crowded; regular; 2 -rowed.

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

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 1.6–2.6 mm long; falling entire.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume orbicular; 0.5 mm long; 0.3–0.5 length of upper glume; 0.2–0.4 length of spikelet; membranous; pallid; without keels; 0–5 -veined. Lower glume apex truncate. Upper glume elliptic; 0.6–0.8 length of spikelet; membranous; without keels; 5 -veined. Upper glume lateral veins transversely connected at apex. Upper glume apex obtuse, or acute.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 5 -veined; obtuse, or acute. Fertile lemma elliptic; 1.2–2.4 mm long; indurate; dark brown; shiny; without keel; 5 -veined. Lemma surface granulose; unwrinkled, or rugulose. Lemma margins involute. Lemma apex obtuse, or acute. Palea reflexed at apex; indurate.

DISTRIBUTION Africa: north, Macaronesia, west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, south, middle Atlantic ocean, and western Indian ocean. Asia-temperate: western Asia and Arabia. Asia-tropical: India, Indo-China, and Malesia. North America: north-central USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Paniceae. SAR 1999.

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