This beetle, which seems to be a longhorned borer beetle (family Cerambycidae), was crawling along the side of the dead tree shown below. At first I was fooled by its bold black-and-yellow pattern and thought it was a wasp. A closer look revealed the tell-tale shape of a beetle. I am not sure what species this is, despite its bold pattern.
Update: The beetle was identified at BugGuide as Strophiona tigrina, one of the flower longhorns (Lepturinae).