The Pearleaf Blister Mite (Eriophyes pyri) is an insect in the Eriophyidae family of leaf mites. It is considered to be a pest in fruit orchards. It is a leaf gall. It is related to spiders.
The Pearleaf Blister Mite is tiny and whitish. It produces visible galls that look like yellow rice on the top surface of leaves. The galls are domed with openings. Initially, the galls are yellow-green, and then they turn brown.
The gall is extrememly small, about 2-5 millimetres (0.2 inches) long, but it is spread across many leaves.
It is common across the globe, particularly in Europe, on pear trees (Pyrus sp.) and also Rosaceae trees, such as apple, mountain ash, and hawthorn trees. It does not live on the leaf surface – it lives within the spongy parenchyma and, in winter, it hibernates in the buds.
The gall of the Pearleaf Blister Mite is seen more than the white Mites. The galls are seen from late spring and throughout summer and autumn. After autumn, the Mite moves to look for a new plant to live on.
The female Pearleaf Blister Mite lays eggs in the gall. When the eggs hatch, the adults and young move out of the galls and feed on leaves and flowers.
Location of photographs: Paris, France
Photographer: Martina Nicolls
Martina Nicolls: SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM