Narrow Lichen Case-bearer Dahlica triquetrella
Another Bagworm Moth of which the bag is better known then the animal inside. The bag is constructed of grains of sand. Often also particles of dead insects are used, especially the shields of very small beetles. The bag has a delicate structure and usually has a very light colour. Sometimes however you might come accross a bag which is more richly decorated with bigger insect parts. The larva spends its entire life inside the bag and pupates inside as well. Adult males leaf the bag and fly off to search a female. Adult females of the Narrow Lichen Case-bearer look like larva and are not able to fly. In stead they climb out of their bag, climb on top of it and wait for a male. After mating she deposits her eggs on the outside of the bag and dies. In most of Europe though, males have never been seen. Females simply climb out of their bag, lay eggs and die, without the interference of a male. This is called parthenogenetic reproduction, a very usual way of reproduction among plant lice. In our parts of Europe males are extremely scarce and most females will lay eggs parthenogenetically.
