Cochineal - Biology

Biology

Cochineal insects are soft-body, flat, oval-shape scale insects. The females, wingless and about 5 millimetres (0.20 in) long, cluster on cactus pads. They penetrate the cactus with their beak-like mouthparts and feed on its juices, remaining immobile. After mating, the fertilised female increases in size and gives birth to tiny nymphs. The nymphs secrete a waxy white substance over their bodies for protection from water loss and excessive sun. This substance makes the cochineal insect appear white or grey from the outside, though the body of the insect and its nymphs produces the red pigment, which makes the insides of the insect look dark-purple. Adult males can be distinguished from females in that males have wings, and are much smaller in size than females.

It is in the nymph stage (also called the crawler stage) that the cochineal disperses. The juveniles move to a feeding spot and produce long wax filaments. Later they move to the edge of the cactus pad where the wind catches the wax filaments and carries the cochineals to a new host. These individuals establish feeding sites on the new host and produce a new generation of cochineals. Male nymphs feed on the cactus until they reach sexual maturity; when they mature they cannot feed at all and live only long enough to fertilise the eggs. They are therefore seldom observed. In addition, females typically outnumber males, due to environmental factors.