This insect is a plant sap eater.
These animals live in groups.
Generally black, brown and green.
The physical size is very small just no more than 1 - 2 mm.
Since this insect is a very destructive plant pest, it is the enemy of the farmer.
Because the damage caused to the leaves and young shoots.
Aside from being a destroyer of aphids plants may invite ants to come because the liquid contains honey or sweet.