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Thick-headed Fly - Physocephala tibialis

Thick-headed Fly - Physocephala tibialis
Amherst, Massachusetts, USA
August 26, 2004
Found in a field near goldenrod. Anyone have any ideas?

Moved from Physocephala.

This is P. tibialis
Taken together, the dark discal cell; black cheeks; and black facial grooves (visible above base of proboscis here)...are all diagnostic of that species.


same as my comment on

Thick-headed fly
Either Physocephala or Physoconops, can't keep 'em straight:-). Did you know these flies are parasites of adult bees and wasps? The female fly actually molests its host in midair, and forces its egg between the segments of the host's abdomen. Talk about a drive-by shooting!

Physoconops sp.
Thanks Eric,

Definitely a Physoconops, especially after seeing these images on Cedar Creek's site. I'll hafta make a quick guide page...

What I'll do is include both possible genus (Physocephala & Physoconops) on a guide page until we can sort the images out...sound good?

Thick-headed fly?
Take a look at Troy's image:

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