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.

Alopecurus heleochloides

HABIT Annual; caespitose. Culms geniculately ascending; 3–8 cm long; 2–3 -noded. Culm-internodes distally glabrous. Lateral branches lacking. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface. Ligule an eciliate membrane; 2–3 mm long; obtuse, or acute. Leaf-blades 4–10 cm long; 2–3 mm wide; flaccid. Leaf-blade surface scaberulous; glabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle; shorter than basal leaves; subtended by an inflated leaf-sheath; embraced at base by subtending leaf.

Panicle spiciform; ovate; loose; 1–1.5 cm long; 0.6–0.8 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; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; truncate; 3 mm long; 1.5 mm wide; falling entire.

GLUMES Glumes free; similar; shorter than spikelet, or reaching apex of florets; recurved at apex. Lower glume oblong; 3 mm long; 1 length of upper glume; membranous; much thinner above; much thinner on margins; 1-keeled; 3 -veined. Lower glume primary vein ciliolate. Lower glume lateral veins distinct; convergent at apex. Lower glume surface hispidulous; hairy on veins. Lower glume apex obtuse. Upper glume oblong; 3 mm long; 0.9–1 length of adjacent fertile lemma; membranous; much thinner above; with hyaline margins; 1-keeled; 3 -veined. Upper glume primary vein ciliolate. Upper glume lateral veins convergent at apex. Upper glume surface hispidulous; hairy on veins. Upper glume apex obtuse.

FLORETS Fertile lemma oblong; 3 mm long; membranous; keeled; 5 -veined. Lemma margins connate below; with 0.75–0.8 of their length connate. Lemma apex obtuse; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5–0.6 way up back of lemma; straight; 1–1.5 mm long overall; not or scarcely exserted from spikelet. Palea absent or minute.

FLOWER Lodicules absent. Anthers 2; 1 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Disseminule comprising a spikelet.

DISTRIBUTION South America: southern South America.

NOTES Aveneae. Hackel 1996.

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