Corchorus trilocularis L.

Global description
 
Corchorus trilocularis is an annual herb that can become sub-woody, reaching up to 1 m in height. The stem is hairy, the leaves are alternate, simple, stalked with linear stipules at the base of the petiole. The lamina has a variable shape, oblong to oval with rounded or acute apex, rounded base and serrated margin. The first tine of the base is bent backward and extended by a filament. The flowers are solitary, opposite the petioles. They are large, yellow in colour, the sepals and petals free and with many stamens. The fruit is a fusiform capsule, opening in 3 to4 valves containing numerous angular seeds.

Cotyledons
 
The cotyledons are orbicular to oval. They are carried by a long petiole, 5 mm long. The leaf blade is 5 mm long and 4 mm wide. The top and the base of the blade are rounded. The leaf blade is marked with 3 veins from the base.
 
First Leaves
 
The first leaves are simple and alternate. They are stalked and framed by linear stipules. The lamina is elliptic lanceolate, 2 to 4 cm long and 6 to 10 mm wide. It is marked with 5 to 7 pairs of lateral ribs. The margin is dentated. The first tine on each side of the base of the blade, is bent backward and extended by a filament. The stem is densely hairy.
 
Growth habit
 
The plant is erect. It is moderately branched, especially at the base. It reaches up to 1 m high.
 
Underground System
 
The plant has a taproot system.
 
Stem
 
The rod is cylindrical and solid. It is robust and densely hairy, sometimes sub-woody at the base.
 
Leaf
 
The leaves are simple and alternate. They are held by a long stalk of 5 to 15 mm. The stalk is finely pubescent, framed at the base by two acute linear stipules, 0.5 to 1 cm long, with a ciliated margin. The leaf blade has a variable shape, oblong, narrow or broadly oval or elliptical, rounded at top, wedged or acute and wedged or truncated base. It is 2 to 7 cm long and 0.5 to 3.5 cm wide. The margin is dentated. The first tine at the base of the blade, is bent backward and extended by a filament which may be 5 to 15 mm long and purple in color. The leaf blade is trinervate at the base and marked by many pairs of secondary veins. Both sides are glabrous or more or less hairy. The leaves are bright green in colour.
 
Inflorescence
 
The inflorescences are in cyme of 1 to 3 flowers held by a short peduncle of 1 to 2 mm opposite to the petioles.
 
Flower
 
The flowers are supported by a short pedicel of 1 to 2 mm subtended by a linear bracteole. The calyx consists of 5 free sepals, obovate in shape, acute apex. They are 6 to 10 mm long and hairy on the dorsal side or only at the base. The corolla is formed of 5 free petals, obovate, rounded top and narrow base of the same length or slightly shorter than the sepals. The corolla is yellow. The stamens are numerous (40 to 60). The ovary is sub-cylindrical with 3 or 4 loculus, topped with a short style. It is covered with appressed pubescence.
 
Fruit
 
The fruit is a dehiscent capsule, blackish brown in colour, cylindrical, with 3 or 4 corners and ribbed longitudinally. It is more or less erect. It measures 3 to 5.5 cm long and 2 to 3 mm in diameter and has at the top a short spout. The outer wall is covered with little stiff bristle tufts of 3 to 7 hairs. Each capsule contains a large number of seeds.
 
Seed
 
Seeds are of angular shape, truncated at both ends. They are 1 to 1.2 mm long. The seed coat is smooth and blackish.

Origine

Corchorus trilocularis is native to tropical Africa, Arabia until India.

World distribution
 

Widespread in the tropical zones of Africa, and introduced in Indonesia (Java), Australia, New-Caledonia, Maagascar, Mauritius and Rodrigues and in Central America;

https://www.gbif.org/species/3152081