Blister Beetles (Meloidae)
Blister beetles are medium-sized beetles (3-70 mm), with a variety of colors and forms. The abdomen generally extends beyond the leathery elytra, giving the body a softer feel than most other beetles. They earned their name due to the toxin, cantharidin, that can cause blistering of human skin. Human health issues involving meloids have a long-documented and colorful history, as cantharidin from Lytta vesicatoria, or the "Green Spanish-fly," has been erroneously used as an aphrodisiac or cure for impotency. However, consumption of cantharidin leads to serious health issues including death. This toxicity can also poses problems for livestock when the beetles feed on alfalfa and are subsequently incorporated into hay.
Blister beetles exhibit an interesting dichotomy of larval development and hosts/prey. The larvae of most genera feed on the provisions and larvae of native ground nesting bees, however, the larvae of other genera feed on grasshopper eggs. Adults are phytophagous, feeding on a combination of stems, leaves, and flowers, including petals, pollen, or nectar; food plant specificity and the part(s) of the plant consumed vary among species. Foraging and mating aggregations often form on the food plants but may be short-lived. These aggregations can number in the hundreds of individuals and sometimes complete disperse within a day. Initial work is focusing on identifying the blister beetle species which inhabit specific regions. A state survey of Wisconsin Meloidae was completed and I am working on Missouri, San Diego County, eventually extending to the entire state of California. Methods include field collecting and reviewing previously collected specimens at other collections (e.g. museums). In addition to developing a species list and distribution for each species, field surveys will more completely describe food plants and other biological aspects of these beetles. Taxonomic uncertainty exists within several genera of blister beetles including Zonitis and Nemognatha. More accurately defining species within these groups will help inform the regional surveys and will likely require a combination of morphological and genetic analyses. Research Tasks 1. Conduct region surveys of the blister beetle fauna. Completed: Wisconsin In progress: Missouri, San Diego County, and California Includes describing the geographic distribution, habitat (including food plants), and phenology 2. Assess the generic and species delineations of Zonitis and Nemognatha. |