14 April 2008: I'm not a taxonomist but have been interested in this species, which I can find locally in Nova Scotia. Apparently D. baumhaueri is an older synonym for the more recently preferred D. hyalipennis, according to a thread to be found under "Dioctria" on Bugguide.net. I don't know if this is controversial (Meigen name), but most seem to prefer D. hyalipennis. Great photo, a female.
