Saw this (possible) mating ritual…
November 24, 2009
Although I saw the two bugs interacting for some time, I have no idea what they are after having looked here and there for an answer.
Big Bend National Park
These courting Robber Flies are gorgeous. The male is flying. We believe they are in the genus Laphria, but we cannot find an exact match on Bugguide. The closest is Laphria trux but it has black legs, not red ones like the individuals in your photo. Last week we got assistance from an expert in Robber Flies, Dr. Robert A. Cannings, Curator of Entomology from the Royal British Columbia Museum. We are writing to him again for assistance.
Hi Daniel: I’m sure this is a Heteropogon. There are a number of
species in Texas (and I’m not familiar with them) but this may be H.
patruelis, which is relatively big and has a red abdomen. I’ve sent the
photo to Eric Fisher to see if he can help.
Update from Robert A. Cannings and Eric Fisher
November 30, 2009
Hi Daniel: Here is Eric Fisher’s reply about the Heteropogon. There’s no one better at identifying most NA asilids, so I doubt if you’ll get a better answer.
Yes, this courting pair do look like Heteropogon patruelis — especially in overall coloration. Only puzzling thing is I can’t really see signs of the patches of erect black & white hairs on the midlegs of the male (I assume the extended legs are the fore pair, and the dangling ones are the midlegs; hard to tell because the leg-base area is so dark).