These beetles when crushed cause nasty blisters on your skin thus the name “Blister Beetles”. They are common in South Africa and are often used as an aphrodisiac called the “Spanish Fly”.
These soft bodied hypermetamorphic beetles are part of the Meloidae family and there are over 2 500 species world wide. They are common insects which feeds on the flowers and foliage of various plants and crops.
These beetles are black with either yellow or orange blotches which serves as warning colours for possible predators. Blister beetles vary by species in shape, size and colour. Their bodies are elongate and cylindrical in shape. They are toxic to vertebrates because of the caustic chemical they produce (Cantharidin - cause irritation, swelling, blistering and even death).
The Cantharidin can be used medicinally to remove warts and a viral skin infection called molluscum contagiosum.