Amaranthus spinosus

Description: Amaranthus spinosus is an erect, many-branched annual herb growing up to 1.5 m. The stem is smooth, robust, cylindrical and often reddish. The leaves are simple and alternate, glabrous or with sparse hairs on the main veins below, often diamond-shaped, long petiolate, up to 9 cm. They are dotted with numerous translucid spots; the venation is well marked. The leaf axils bear pairs of fine and slender spines. The small green flowers are grouped in clusters in the axils of the leaves and in branched terminal spikes. The fruit is a dehiscent capsule that splits open at maturity (dehiscent); it contains a single smooth, black, lens-shaped seed. 

Flowering and Fruiting: December to April.

Economic Importance: Its use is declining, and it is acquiring the status of a famine food. It has a bitter taste and is usually eaten in small quantities as a substitute when no other vegetables are available. Amaranthus spinosus is also used as forage and said to increase the yield of milk in cattle. 

Reference: https://en.wikipedia.org/wiki/Amaranthus_spinosus