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Lytta vesicatoria

Spanish fly

Description

Lytta vesicatoria, also known as the Spanish fly, is a conspicuous green metallic blister beetle from the family Meloidae. It occurs in southern and central Europe, where adults appear in late spring and early summer. The beetles are active during hot daylight hours and aggregate in large numbers on host trees, feeding on the foliage. They prefer ash (Fraxinus), but also feed on lilac, privet, elm, maple, poplar, catalpa, rose, and other deciduous plants. Heavy feeding can result in partial or complete defoliation, especially on young trees, which may significantly worsen their condition. Larvae develop in the nests of solitary bees, where they prey on bee larvae and stored pollen. The species has one generation per year.

The body of Lytta vesicatoria contains the toxic substance cantharidin, which can cause painful blisters upon contact with the skin. If ingested, cantharidin is highly dangerous – it can damage the kidneys and lead to severe poisoning. This compound was historically used in folk medicine, but its effects are extremely risky. Therefore, caution is strongly advised when handling the beetle.

Symptom

Chewed leaves with irregular edges, mostly in upper tree canopy; remaining veins may remain intact.

Tree Species: Ash, Maple, Catalpa, Boxwood, Lilac, Rose, Poplar

Part of a plant- attacked: Leaf / Needle

Pest significance: Less harmful

Pest Category: Insects

Invasive Species: No

Present in EU: Yes