Leersia hexandra Sw.

Global description
 
Leersia hexandra is underwater poaceae, vivacious, creeping, with dense rhizomes forming a tufted stand on hydromorphic soil. The rhizomes are long, creeping, radicand at the nodes. The culms are more or less prostrate or erect, reaching up to 90 cm in height. The distichous leaves are glaucous, spreading linear blade, pointed, and measuring 5 to 20 cm long and 2 to 8 mm wide. The leaf with hanging edges or even sharp, are unpleasant to the touch. The inflorescence is a narrow panicle resembling inflorescence of rice when small. The spikelets are solitary, up to 3 to 5 mm long, arranged unilaterally on the axis; they look like small grains of paddy of reddish or purplish color.
 
First leaves
 
The first leaves are very narrow rolled, vertically erect. The prefoliation is rolled.
 
General habit
 
Creeping grass, with developed and branched stolons and rhizomes, with many culms, more or less prostrate or erect, reaching up to 90 cm high.
 
Underground system
 
The roots are fibrous and with numerous adventitious roots which appear at the nodes.
 
Culm
 
The culm of the grass is cylindrical, slender, more or less prostrate at the base and then straightened, glabrous  but with hairy nodes with  white reflected hair.
 
Leaf
 
The leaves are alternate, simple. The sheath is glabrous or finely scabrous, loose pubescent  with reflected hairs, fitted on the top with two small pointed auricle. Ligule is membranous, oval or truncated, 1 to 3 mm long. The lamina is linear, spreading, 5 to 20 cm long and 2 to 8 mm wide, attenuate base, narrower than the top of the sheath, and acute apex. The upper side is glabrous, the underside is finely scabrous. The margin is scabrous making the edges of the hanging leaves r sharp and unpleasant to the touch.
 
Inflorescence
 
The inflorescence is a narrow elliptical panicle, 5 to 12 cm long and 1 to 4 cm wide, with slender solitary branches more or less erect and bare in their lower part.
 
Spikelet
 
The spikelets are solitary, shortly pedicellate, oblong, without ridge, 3 to 5 mm long, yellow-green to reddish or purplish in colour. They are arranged unilaterally on the narrow zigzag rachis. The glumes are absent, reduced to a clear ring atop the pedicel. The flower has a 5-rib navicular lemma, very compressed, keeled (keel and margin strongly scabrous to pectinate). Palea, narrower than the lemma, 3-veined, is compressed keeled with scabrous keel and margin.
 
Grain
 
The grain is obliquely oblong, 1.5 mm long, it remains included in the lemma.

Worldwide distribution

Leersia hexandra is widely distributed in all tropical and subtropical regions.

https://www.gbif.org/species/2702901