Life cycle, dynamics populations

• Sparganothis pilleriana overwinters as a young caterpillar that entered diapause almost immediately after hatching. It measures almost 2 mm and its body is greenish yellow with the head and the first thoracic segment black. It is localized in cracks in wood or under the bark of vines. As soon as the spring conditions are favorable, the caterpillar resumes its activity and moves towards the buds at bud break on the end of which it begins to feed. To protect themselves, the larvae weave silken sheaths in which they gather the leaves and future inflorescences. As soon as they have reached 1 cm in length, in May, the caterpillars descend from the ends towards the middle of the vegetation in the adult leaves and inflorescences at the level of which they weave a network of dense bristles

• The activity of the larvae pushes them to seek shade and the absence of sun but they are observed regularly during the day, preferably in the early morning or at the end of the day. The successive molts of the larvae last about ten days each, or 40 to 50 days of larval activity in general.

• Around mid-June, the caterpillars begin to pupate to give pupae in shelters made from the leaves curled up by the weaving of the larvae. This entry into pupation lasts until mid-July. This pupation will last about ten to twenty days depending on the climate.

• The adults appear from mid-July, variable by region. Butterflies appear over a period of about a month. They mate at dusk and early night.

• The female spawning takes place shortly after and occurs from early July to early August on vine leaves sclerosis d ' eggs , or ooplaques, which can reach a hundred eggs, an apple green color. A female can lay on or under the leaves, up to 300-400 eggs in total. The incubation of the eggs lasts about ten days. All the eggs in an oopplate are obviously the same age since they are laid at the same time: they therefore all hatch at the same time. The appearance of these caterpillars varies from late July to August. They do not feed and directly seek shelter to put themselves into larval diapause. 

• Synoptic of the development of Sparganothis pilleriana on vines (figure 1)