Master Blister Beetle
Lytta magister
Photo taken March 25, 2009 along the Echo Canyon trail to the summit of Camelback Mountain in Phoenix, Arizona, USA. Just minutes before it had emerged from the soil where it had matured as a larva feeding on bee's nest..
Among the most conspicuous of insects in the Sonoran Desert spring are Blister Beetles in the family Meloidae. And Master Blister Beetles are probably the most common species of blister beetle. They feed on the petals and pollen as adults but live an entirely different life as immature larvae. Most Blister Beetles tend to have bright, aposomatic coloration set off by black. This is a warning that these beetles often contain noxious or poisonous compounds; birds and other insectivores tend to avoid meloids. The toxic properties of blister beetles have long been known including a European species, Spanish Fly.
The larvae are parasitic in the nests of ground nesting bees or other ground nesting insects. The tiny, first stage larvae are mobile and seek out a suitable host. Once they attach to a host they become immobile drawing sustenance as they grow.
Another common and conspicuous Sonoran Desert blister beetle is the Iron Cross Blister Beetle -- Tegrodera aloga.