The small about 3 millimeters long silvery white moths (also leaf bag moths) are a family of butterflies, The family includes about 1,000 species worldwide, of which about 230 are also distributed in Europe. Many of them specialize in a single host plant and cause a characteristic of each type of damage. In case of heavy infestation it can come to growth depressions. The little butterflies fly especially at dusk. They have a well-trained proboscis and long antennas. In the resting position, the front body is usually raised. The narrow wings often have long fringes.
The tracked have in the first instar larvae forward facing mandibles (mouthparts) that allow piercing and sucking out of cells, or serve for chewing plant and animal food. The caterpillars eat their way through the leaf tissue and create numerous, typically shaped, long feeding passages (miniature tunnels). The sheet dies around the corridors, turns brown and dries up completely in case of heavy infestation. In the later stages larvae of different ages can look very different. The oldest larval stages live in many species in scrolled leaves and gnaw their insides.
The North American vine moth Phyllocnistis vitegenella has also been found in European vineyards since the early 1990s. First, the pest was in Italy (Veneto, Puglia) spotted, now he has too Slovenia and the Switzerland (Ticino) reached. The moths spend the winter in diapause (temporary interruption of development) under the bark of a vine, In spring the eggs are laid on the first unfolded leaves. The first mini-aisles are already visible in May. The footless, whitish larvae or caterpillars go through five stages of development. There can be four generations per year.
Despite the conspicuous damage, the American leafminer is considered a secondary pest against which direct control measures rarely need to be taken. After analyzes of the research station Changins (Switzerland) could become a chemical control by insecticides as not effective. Experiments conducted in Italy have shown that native Hymenoptera parasitize the larvae, which is a biological, environmentally friendly solution. See a list of all pests below Vine enemies,
Picture left: Helmut Deutsch butterfly research