Setaria arenaria

HABIT Annual; caespitose; clumped densely. Culms geniculately ascending; 30–100 cm long. Culm-internodes smooth; distally glabrous. Leaf-sheaths loose; pubescent; with tubercle-based hairs; outer margin hairy. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Leaf-blade base broadly rounded. Leaf-blades 5–15 cm long; 2–7 mm wide. Leaf-blade surface scabrous; rough on both sides; glabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; continuous, or interrupted; 2–9 cm long; 0.5–0.8 cm wide. Primary panicle branches accrescent to a central axis; with evident branchlets on axis. Panicle axis hispid, or pilose.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 2–6 in the cluster. Involucre composed of bristles; free throughout; 2–8 mm long. Involucral bristles persistent; few; in one whorl; 1–4 per spikelet; flexible; glabrous. Pedicels oblong.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 2.5–3 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.5 length of spikelet; membranous; without keels. Lower glume apex acuminate. Upper glume ovate; 1 length of spikelet; membranous; without keels.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; membranous; 5 -veined. Fertile lemma elliptic; dorsally compressed; 2.5–3 mm long; indurate; yellow, or light green; without keel. Lemma surface rugulose. Lemma margins involute. Lemma apex acuminate. Palea involute; indurate.

DISTRIBUTION Asia-temperate: China.

NOTES Paniceae. Fl China 2007.

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