Setariopsis latiglumis

HABIT Annual. Culms erect; (30–)60–100 cm long; without nodal roots, or rooting from lower nodes. Culm-internodes ridged; smooth, or scaberulous. Culm-nodes pubescent. Leaves cauline. Leaf-sheaths keeled; hispid; with tubercle-based hairs. Ligule a fringe of hairs. Leaf-blades 10–30 cm long; 5–9 mm wide. Leaf-blade surface scaberulous; pilose; sparsely hairy. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted, or spiciform; linear, or lanceolate; truncate or rounded at the ends, or tapering above; 4–20 cm long; contracted about primary branches. Primary panicle branches bearing spikelets almost to the base; sterile at the tips. Panicle branches flexuous; angular; hispid, or pilose.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1 in the cluster. Involucre composed of bristles; 7–10 mm long. Involucral bristles persistent; 1 per spikelet; antrorsely scaberulous. Pedicels cuneate; 0.5 mm long; scabrous.

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

GLUMES Glumes dissimilar; with lower narrower than upper; exceeding apex of florets, or reaching apex of florets; thinner than fertile lemma. Lower glume oblate; gibbous; 1–1.3 mm long; 0.3 length of spikelet; membranous; without keels; 2 -veined. Lower glume apex obtuse, or cuspidate. Upper glume oblate (spreading); gibbous; 3 mm long; 1 length of adjacent fertile lemma; herbaceous, or indurate (at maturity); firmer above; without keels; 17–19 -veined. Upper glume lateral veins ribbed; without cross-veins, or with cross-veins. Upper glume apex entire to erose; obtuse to cuspidate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret oblong; 3–3.5 mm long; 1 length of spikelet; membranous, or coriaceous (at maturity); firmer above; 9 -veined; sulcate (lyrate); scaberulous; emarginate. Palea of lower sterile floret pilose. Fertile lemma elliptic; dorsally compressed; 2–3 mm long; indurate; pallid; keeled; lightly keeled; keeled above; 5 -veined. Lemma surface tuberculate. Lemma margins involute. Lemma apex cuspidate. Palea elliptic; 0.9–1 length of lemma; indurate; thinner on margins; 2 -veined. Palea surface tuberculate.

FLOWER Anthers 3; 0.5–0.7 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; ovoid.

DISTRIBUTION North America: Mexico.

NOTES Paniceae. TB.

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