Ochrogaster lunifer is the scientific name for the Bag-shelter moth and its Processionary caterpillars
Eggs (October – December)
Egg masses of Ochrogaster lunifer are laid in spring. The egg mass may be white (ground nesting form) or golden (elevated nesting form) depending on the nest location. The developmental time is approximately 3 – 4 weeks.
Larvae (December – October)
First instar larvae hatch from eggs after 3-4 weeks and continue to live inside the egg mass without feeding. After approximately 14 days, they become a 2nd instar larva (see below) and start feeding on the leaves of the host tree. Ochrogaster lunifer has 8 larval instar stages before they pupate and become a moth. They continuously feed in the first half of their larval life (December to May) and the last half (May to October) consists of diapause (resting underground).
Progressive growth of an O. lunifer larva
Pupa (September – November)
After the larvae diapause over winter (May to October), pupation starts in Spring. The process takes 2-4 weeks and then adults emerge.
Adults are beige to brown/grey with white markings on the wings. The wing colouration differs depending on their nesting form. Ground nesting forms tend to have dark brown wings with white anal tuft scales (end of the abdomen); whereas elevated nesting forms have lighter brown wings with golden anal tuft scales. Only females have a tuft of irritating scales and hairs, which they use to cover and protect their eggs. The adults have non-feeding mouthparts and live for only a few days.