Phyllanthus urinaria L.

Global description

Phyllanthus urinaria is a more or less erect plant, usually bare toward the base, with single stem or slightly branched, reddish, narrowly winged between the stipules and the lower node and 1 to 2 lines of hairs. It is 10 to 45 cm high, but usually smaller, or the plant is more or less prostrate and reaches only up to about 10 cm. The leaves are oblong, acute to rounded at the apex, and mucronate , dark green on upper surface, paler on lower surface, carried by short branches, making them to look like compound leaves. Female flowers are especially present at the base of the branches. The fruits are globular capsules with bumpy surface.
 
Cotyledons

The cotyledons are sub-sessile, with oblong blade having rounded apex and base. They measure 6 mm long and 3 mm wide.
 
First leaves

First leaves simple, alternate, obovate or oblong, on an erect or reddish prostrate stem, narrowly winged. The lamina is 5 to 7 mm long and 3 to 4 mm wide. The base is wedged and the apex rounded mucronate or apiculate. The margin is entire, often tinged with red and is very finely scabrous and faces are glabrous.
 
General habit

Annual plant, erect, 10 to 45 cm high, single stem or slightly branched, narrowly winged at the internodes.
 
Underground system

The plant has a taproot system.
                                                                                                                               
Stem

The stem is roughly tetragonal, full, narrowly winged at the base of the stipules between the lower internodes, generally having 1 to 2 lines of bristle. The stem is usually reddish in color. The stem exudes a transparent latex when it is cut.
 
Leaf

Leaves are simple, alternate, very close, sub-sessile. Those on the main axis have at the base, oval stipules, long acuminate, scarious, significantly auriculate at the base, or even peltate, sometimes the auricle attenuated into basal tip. The leaves of lateral branches have scarious stipules significantly reduced and non auriculate. The lateral branches with defined growth, look like compound leaves with alternate leaflets. The lamina is oblong, apiculate, acute to obtuse and mucronate at the apex, more or less rounded and slightly asymmetrical at the base, 7 to 12 mm long and 2.5 to 6 mm wide. The margin is entire, tinged with purple and scaberulous. The faces are dark green on the upper surface above, paler on the lower surface and smooth, the pinnate venation is clearly visible.
 
Flower

Flowers solitary or in small groups at the leaf axils of lateral branches. The flowers of the basal part of the branches are females and solitary; the distal male flowers are in small groups. Female flowers with short pedicel (0,5 mm) and 1-2 bracts at the base, usually facing down. The sepals are narrowly ovate, 1 mm long with membranous margin, white to yellowich coloured. The disc is a thin ring, flattened, the ovary is spherical distinctly verrucous. Male flowers with 6 white sepals elliptic to obovate and disk with 6 discoid green lobes and 3 stamens. After opening of capsules and falling of shells, all pedicels, bearing the sepals and persistent basal disk, are stiff and regularly facing down.
 
Fruit

The fruit is a capsule with 3 loculus, 2.5 mm in diameter, never smooth, covered with warts more or less clear, these warts are reduced to mere roughness by the growth of the fruit.
 
Seed

Seed trigonal, about 1.5 mm long, crossed on the back with transverse ridges, and having deep excavations on the sides.

Origin

Phyllanthus urinaria is native to India, South East Asia and Australia

Worldwide distribution

This species has been introduced in the Indian Ocean islands (Comoros, Madagascar, Mauritius, Reunion), Central and Western Africa, Southern USA, Central and South America.

https://www.gbif.org/species/5382780