Thread subject: Diptera.info :: More Fun with Pyrgotidae

Posted by Stephen on 19-11-2006 14:51
#1

Reviewing my photographs from last April from Mississippi (far South of the USA) I came across my Pyrgotid images. Now I am starting to wonder, do I have two different species here?

These were attracted to lights, 14 April 2006.

I will post the two flies first, then some detailed views. I think Fly #1 is Pyrgota undata.

Comments appreciated. Two different species? Both female? Steyskal says in Pyrgotidae the abdomen is usually elongated, and that in females "segment 7 sometimes longer than rest of abdomen."

Edited by Stephen on 19-11-2006 14:52

Posted by Stephen on 19-11-2006 14:54
#2

Fly #2. Different species?

Posted by Stephen on 19-11-2006 14:55
#3

Here are the abdomens compared, Fly #1 and Fly #2.

Posted by Stephen on 19-11-2006 14:58
#4

The heads compared.

What on earth is going on with Fly #2 and what appear to be doubled antennae? I thought perhaps there was a second fly under the top one and that they were mating, but if so that second fly doesn't show. Or is this simply a species that has this bizarre doubled antenna?

Posted by Steve Gaimari on 19-11-2006 18:35
#5

For Fly#2 you have a different angle on the head so that you can see the mouthparts. That is what looks like the second pair of antennae - the mouthparts with the paired maxillary palpi.

Posted by Stephen on 19-11-2006 20:54
#6

Ah, that explains the mouthparts question, thanks, Steve! The angle was really the same for the two photos, so Fly #2 must have been extending his mouthparts forward for some reason while Fly #1 wasn't.