TUCSON, AZ (Tucson News Now) - They're fierce looking creatures and now that spring has arrived in Arizona, Iron Cross Blister Beetles are out in full force. These brightly colored and flashy beetles make their appearance in Arizona and California this time of year.
According to http://www.arizonensis.org, these beetles normally emerge in large numbers in mid to late spring and move together in bands crawling or running across the ground. They feed on succulent leaves and flower petals. The larva stage is subterranean and likely is parasitic in nests of ground-nesting bees.
Iron Cross Beetle's conspicuous coloration is related to the fact that they carry toxins that can interfere with the vertebrate nervous system.