Posted by Stephen on 31-08-2006 01:58
#1
Is this another Ephydridae? Photographed on the shore of a large pond. Size 5.0 mm. West Virginia USA, late August.
Thanks for help with the ID.
Posted by Tony Irwin on 31-08-2006 10:35
#3
Stephen - your flash shows up the suture across the thorax (as a shallow crease running across, just in front of the wing bases). This means it is one of the caylpterate families.
The straight vein M suggests it is not Tachinidae, Calliphoridae, Sarcophagidae, etc. and the general body shape also excludes Scathophagidae, so it's a choice between Anthomyiidae, Muscidae and Fanniidae.
There's no dorsal bristle other than the preapical on the hind tibia, so it's not Fanniidae. And the anal vein does not appear to reach the wing margin, so the chances are it's not an anthomyiid.
In time you will find all this reasoning happens automatically in a split second. (And sometimes gets it wrong! :D) But I'd agree with Paul on this one.
Posted by Stephen on 31-08-2006 11:03
#4
Gentlemen, thanks so much for the help! So much to learn. I think I am absorbing some of this!
I would not have thought of Muscidae because the wings are relatively long and held one over top of the other instead of out to the sides. Such big eyes too. But not all Muscidae look like the House Fly I suppose. I'll have to look at more Muscid pictures to get a feel for the variety in the family.
Thanks again!