Tachinid fly - Epalpus signifer

Corrected Title

Thanks so much for your help Robin and Joel. I've corrected the title for this pic. Joel, I missed your excellent pic when I browsed through the flies on BugGuide, but because my colors are a bit different, I might not have seen the match anyway. Tony's head shot is a Wow.

I don't know flies very well (except for a few of the biting ones :) ). I guess I've seen references to Tachinids but haven't really known what they are. Now that I've read up on them a bit, they look like an interesting group. Has anyone any idea if this is a female? I'm not sure how to tell with flies!-) I'm wondering what they were doing on the scat, and ovipositing females is one of the possibilities.

… Bob Duncan, 2 January, 2005 - 9:40am

Tachinid Resources

Here's a great reference on the Tachinidae from the North American Dipterist Society: http://www.nadsdiptera.org/Tach/Morpho/tachmor.htm
This page has a nice morphology key, and explains the differentiation between Tachinids (hint: it's not just the setae) and other families.

… Bruce Marlin, 2 January, 2005 - 11:51pm

Tachinid Fly

I've also seen these flies on dung in the woods. I think this is in the genus Belvosia. Nearctica lists 15 species from North America - don't know which one this is...

… Robin McLeod, 1 January, 2005 - 10:38am

Tachinid

I agree this is a tachinid, but I think it is Epalpus signifer (1),(2). Both of the other photos in the guide were somewhat tentatively identified as this species, but this photo is certainly a match to those.

… Joel Kits, 1 January, 2005 - 11:10am

I agree. Epalpus signifer

Belvosia is even larger, and the bands are weakly metallic. A great many flies visit dung and carrion, regardless of whether they breed there. The consistency of the medium, and nutritional value, draws them. Most flies feed on liquid food, or regurgitate enzymes to help liquify solid morsels. M-m-m-m:-)

… Eric R. Eaton, 3 January, 2005 - 1:01pm

Epalpus signifer

I found this fly in Colorado Springs in April-May on flowers of Salix irrorata(Bluestem Willow) and Rhus trilobata. Couldnt catch one. The white rump triangle is a good marker in flight.

… Adalbert Goertz, 1 July, 2005 - 12:13am

Tachinid

Thanks, Joel. I agree that Epalpus looks better. I think Belvosia would have a black(er) back and the last TWO abdominal segments bright(er) yellow.

… Robin McLeod, 1 January, 2005 - 2:12pm