A preliminary comparison of cantharidin levels in blister beetles associated with alfalfa production in New Mexico

A preliminary list of the blister beetles of New Mexico was compiled using data based primarily on specimens from the NMSU Arthropod Collection and from field collections in 2007 and 2008. Little information is currently available for these economically important insects in the state. However, this list has expanded during the 2008 season, and continues to increase in size throughout 2009. This is to eventually include other museums in NM and surrounding states. Our current list revealed that a variety of genera and species are present in New Mexico. Most common is the genus Epicauta, which appears to be well represented in alfalfa and rangeland settings. The ultimate goal of this research will be to narrow a broad list of blister beetle species to a short list that are of importance to alfalfa production and maintaining the safety of livestock in the state of New Mexico. Currently the preliminary list of recorded blister beetle species in New Mexico alfalfa consists of seven species, Epicauta andersoni,E. apache, E. immaculata, E. pardalis, E. pestifera, E. sp. and E. uniforma. Cantharidin was extracted from blister beetle specimens by using protocol from Capinera et al. (1985). Cantharidin levels were compared using gas chromatography. These data should provide useful information on the relative toxicity of the alfalfa associated blister beetles in New Mexico.