Onion thrips
develops in six stages: egg, two larval instars, prepupa, pupa, and finally the adult insect. The eggs of the onion thrips (Thrips tabaci) are laid in leaves [...] head and bright red eyes. The colour of the adult depends on the food source. Onion thrips (Thrips tabaci) usually pupate in the ground, although pupae can [...] patches on leaves and the black dots of their excreta indicate their presence in the crop. The vigour of the plant is reduced by loss of chlorophyll.