Cochineal is the name of both a crimson or carmine dye and of the cochineal insect (Dactylopius coccus), a scale insect in the suborder Sternorrhyncha, from which the dye is derived. There are other species in the genus Dactylopius which can be used to produce cochineal extract, but they are difficult to distinguish from D. coccus. The primary biological distinctions between species are minor differences in host plant preferences, in addition to very different geographic distributions. D. coccus itself is native to tropical and subtropical South America and Mexico.
This type of insect, a primarily sessile parasite, lives on cacti from the genus Opuntia, feeding on moisture and nutrients in the cacti. The insect produces carminic acid which deters predation by other insects. Carminic acid can be extracted from the insect's body and eggs to make the dye. Cochineal is primarily used as a food colouring and for cosmetics. (Full article...)