Infested leaves appear blistered on the underside and are often discolored. Their feeding on tender new growth causes leaves to cup and stunts the growth of shoots. Difficult to find even under a dissecting microscope. Egg shells and cast skins can be important clues but they are not as apparent as they are with other spider mites species. A small, delicate fly.
Damage is caused by larvae which feed between the upper and lower layers of leaves.
Two to six larvae typically occur in a single leaf. With a little practice, they are easily found by breaking open a blistered leaf with your thumbnail. Adults are rarely seen. Nymphs cover themselves with white, cotton-like secretions. Mites overwinter as eggs on the undersides of leaves.