This example is in the maculata group of the subgenus Epicauta and may be E. cazieri or E. apache, both of which occur in West Texas. Compare:
I'm hoping to get feedback on BG as well: http://bugguide.net/node/view/1246029
This beetle was feeding on Buffalo Bur (Solanum rostratum) in the dried bed of a cattle tank at about 5100 ft. elevation.
Blister beetles are beetles (Coleoptera) of the family Meloidae, so called for their defensive secretion of a blistering agent, cantharidin. There are approximately 7,500 known species worldwide. Many are conspicuous and some aposematically colored, announcing their toxicity to would-be predators.