Posted by Sundew on 11-07-2008 23:12
#1
Hi,
Yesterday I saw a small
Phasia on milfoil inflorescences. The thorax was black, but the last tergites were grey. Can
Phasia obesa be thus variable?
Thanks, Sundew
Posted by ChrisR on 12-07-2008 09:00
#2
The small
Phasia spp. (
barbifrons,
obesa &
pusilla) can be variable in the dusting on their abdomens. But the key feature for
P. obesa is that the thorax should have dusting - abdomenal dusting isn't important. This fly looks like
Phasia pusilla to me - the face is very silvery and I can't see a yellow haltere :)