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.

Setaria rara

HABIT Annual; caespitose. Culms geniculately ascending, or decumbent; 15–22(–37) cm long; 3–5 -noded; without nodal roots, or rooting from lower nodes. Ligule a fringe of hairs. Leaf-blades flat, or conduplicate; 3–8 cm long; 1–3 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 10–20; single (apparently, when racemes reduced to 1 spikelet), or borne along a central axis; unilateral; 0.3–0.9 cm long; bearing few fertile spikelets; bearing 1–2(–4) fertile spikelets on each. Central inflorescence axis 5–10 cm long. Rhachis narrowly winged; angular; terminating in a barren extension; extension subulate; extension 2–4 mm long. Spikelet packing abaxial.

Spikelets solitary, or subtended by an involucre (actually the extension of a 1-spikelet raceme). Fertile spikelets sessile. Involucre composed of bristles; 2–3 mm long. Involucral bristles 1 per spikelet.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; obtuse, or acute; 3–3.5 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.5–0.6 length of spikelet; membranous; without keels; 5–7 -veined. Lower glume apex acute. Upper glume elliptic; 1 length of spikelet; membranous; without keels; 7–9 -veined. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 5–7 -veined; acute. Fertile lemma elliptic; 3–3.5 mm long; indurate; without keel. Lemma surface rugose. Lemma margins involute. Lemma apex acute. Palea reflexed at apex; with a basal protruberance; indurate; 2-keeled. Palea surface rugose.

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Lazarides.

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