The white-rumped bee fly, Ogcodocera leucoprocta, has no real common name. It likes to visit flowers. Look for it in our native prairies. Apparently, there are only two species of Ogcodocera bee flies in the United States, and O. leucoprocta is the only one known from the eastern states. Leucoprocta means "white anus."
Learn more about the white-rumped bee fly and other bee flies (family Bombyliidae) on their family page.