Spanish Fly (Lytta vesicatoria) : : one of a number of species that are collectively called blister beetles; it and other such species were used in preparations offered by traditional apothecaries. The perceived aphrodisiac properties of L. vesicatoria and its dried cantharides, are a result of its toxicology, specifically, irritant effects it has upon the body's genitourinary track; views of this property are anachronistic alongside modern statements saying the effect is just painful.