Alopecurus japonicus

HABIT Annual; caespitose; clumped densely. Basal innovations intravaginal. Culms geniculately ascending; 20–60 cm long; 1–2 mm diam.; 3–4 -noded. Culm-internodes 2–8 cm long. Leaves basal and cauline. Leaf-sheaths loose; 3–4 cm long. Ligule an eciliate membrane; 2–4 mm long; white; obtuse. Leaf-blades 3–15 cm long; 3–8 mm wide; glaucous; pruinose. Leaf-blade surface scabrous; rough adaxially; glabrous.

INFLORESCENCE Inflorescence a panicle; subtended by an inflated leaf-sheath.

Panicle spiciform; linear; 3–10 cm long; 0.5–1 cm wide. Primary panicle branches accrescent to a central axis; with evident branchlets on axis. Panicle axis with rounded ribs.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels oblong; 0.3–0.8 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 5–6 mm long; falling entire.

GLUMES Glumes free; similar; shorter than spikelet; shiny. Lower glume elliptic; 4.2–4.5 mm long; 1.1 length of upper glume; membranous; light green; 1-keeled; 3 -veined. Lower glume primary vein ciliate. Lower glume apex acute. Upper glume elliptic; 4–4.3 mm long; 0.8 length of adjacent fertile lemma; membranous; light green; 1-keeled; 3 -veined. Upper glume primary vein ciliate. Upper glume apex acute.

FLORETS Fertile lemma ovate; 5–6 mm long; membranous; keeled; 5 -veined. Lemma margins free, or connate below. Lemma apex obtuse; awned; 1 -awned. Principal lemma awn dorsal; arising 0.1 way up back of lemma; geniculate; 10–12 mm long overall; with twisted column. Palea absent or minute.

FLOWER Lodicules absent. Anthers 3; 1 mm long; pallid, or yellow. Stigmas protogynous; terminally exserted; pubescent. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; 2–2.5 mm long. Hilum punctiform. Disseminule comprising a spikelet.

DISTRIBUTION Asia-temperate: China and eastern Asia.

NOTES Aveneae. Koyama 1994.

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