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.

Lasiacis procerrima

HABIT Annual, or perennial; short-lived; caespitose. Culms decumbent; (50–)100–400(–500) cm long; 4–10 mm diam.; firm, or woody; with prop roots. Culm-internodes hollow; distally glabrous. Culm-nodes glabrous. Lateral branches lacking, or sparse. Leaf-sheaths glabrous on surface, or puberulous, or hispid, or woolly; outer margin hairy. Leaf-sheath auricles absent, or erect; 0–2 mm long. Ligule a ciliolate membrane; 0.5–1.5(–2.1) mm long; glabrous on abaxial surface, or pubescent on abaxial surface. Collar glabrous, or pubescent. Leaf-blade base cordate. Leaf-blades linear, or lanceolate; 14–42 cm long; 15–55 mm wide; glaucous. Leaf-blade surface glabrous, or hispid. Leaf-blade margins scabrous; glabrous, or ciliate; hairy at base. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; effuse; (20–)32–120 cm long. Primary panicle branches whorled at lower nodes. Panicle branches bearing distant spikelets; scabrous; glabrous in axils.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; tilted on the pedicel; dorsally compressed; (3–)3.5–4(–4.8) mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma; shiny. Lower glume oblate; (1.4–)1.6–2.1(–3) mm long; 0.5 length of spikelet; membranous; black; without keels; 7–11 -veined. Lower glume surface woolly; hairy at apex. Lower glume apex obtuse. Upper glume ovate; 1 length of spikelet; membranous; black; without keels; 9–11 -veined. Upper glume surface woolly; hairy at apex. Upper glume apex obtuse.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; membranous; 9–11 -veined; woolly; hairy at apex; obtuse. Palea of lower sterile floret 0.75–0.8 length of lemma. Fertile lemma ovate; dorsally compressed; 3.1–3.4 mm long; 1.8–2.1 mm wide; indurate; grey, or black; shiny; without keel. Lemma margins involute. Lemma apex obtuse; with a shallow excavation and woolly. Palea indurate. Palea apex pubescent.

FLOWER Anthers 3; 1.6–1.9 mm long; yellow. Stigmas white.

FRUIT Caryopsis with adherent pericarp; 2.3 mm long; dark brown.

DISTRIBUTION North America: Mexico. South America: Mesoamericana, northern South America, western South America, and Brazil.

NOTES Paniceae. Davidse.

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