A close-up view of part of a blackberry leaf, Rubus fruticosus, mined by the larva of the blackberry pygmy moth, Stigmella aurella. The picture shows the serpentine tunnel made by the larva as it grows by eating the green tissue between the upper and lower epidermis of the leaf. The width of the tunnel increases as the larva grows; in this picture, it began at the top edge of the frame, moved to the right, off-frame, and re-entered the frame just below halfway on the right side. The picture shows that it failed to cross the thickened midrib of the leaf ( running vertically, to left ). The minor veins of the leaf do not obstruct the larva. Stigmella aurella is a micro-moth of the family Nepticulidae. The adult insect has a wingspan of only 3-4mm. Mined leaves are easily found on blackberry leaves, both of wild brambles and of plants grown for fruit. The insect has no economic impact