Leptochloa fusca

HABIT Perennial. Culms decumbent; 60–150 cm long; rooting from lower nodes. Ligule an eciliate membrane; 3–8 mm long; acute. Leaf-blades flat, or convolute; 25–55 cm long; 3–5 mm wide; stiff; mid-green and grey-green. Leaf-blade midrib widened. Leaf-blade surface scabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 10–30; borne along a central axis; erect; straight; unilateral; 7–15 cm long. Central inflorescence axis 15–30 cm long. Rhachis semiterete. Spikelet packing broadside to rhachis; lax.

Spikelets solitary. Fertile spikelets pedicelled, or sessile. Pedicels filiform; 0.5–1.5 mm long.

FERTILE SPIKELETS Spikelets comprising 6–11 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; compressed slightly; 8–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes eventually visible between lemmas. Floret callus evident; pubescent; obtuse; disarticulating obliquely.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 2.1–4.6 mm long; 0.6–0.7 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute, or acuminate. Upper glume oblong; 3.3–7.4 mm long; 1–1.3 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex obtuse, or acute; mucronate.

FLORETS Fertile lemma oblong; 3.2–5.9 mm long; membranous; dark green, or grey; without keel; 3 -veined. Lemma midvein ciliate; hairy below. Lemma lateral veins close to margins. Lemma margins pilose; hairy below. Lemma apex dentate; 2 -fid; mucronate, or awned; 1 -awned. Principal lemma awn from a sinus; 0.3–1.6 mm long overall. Palea 2 -veined. Palea keels scabrous. Palea surface pubescent; hairy on flanks. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 0.2–2.7 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; flattened; concavo-convex; 1.6–1.8 mm long.

DISTRIBUTION Africa: north, west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, south, and western Indian ocean. Asia-temperate: western Asia, Arabia, China, and eastern Asia. Asia-tropical: India, Indo-China, Malesia, and Papuasia. Australasia: Australia. Pacific: southwestern and north-central. North America: northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Eragrostideae. =Diplachne fusca. FTEA.

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