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Photo#157411
A Robber Fly (Almost) from California - Promachus princeps

A Robber Fly (Almost) from California - Promachus princeps
Off Red Rock Rd, ~1 mile east of Hwy 395, just over the border from California, ~28 miles NNW of Reno., Washoe County, Nevada, USA
July 10, 2007
I think this Robber Fly is a male Promachus albifacies, but I'm not sure. I tried to key it in Cole(1), but couldn't obtain a conclusive result (because I didn't know enough to get a good image of the wings when I had it in hand!). Nevertheless, P. albifacies seems good from what I could gather from Cole, and the specimen compares favorably with the BugGuide post below:

     

Photographed near a slow-running creek with modest riparian vegetation (willows, rushes, etc.) in an otherwise arid desert canyon.

Images of this individual: tag all
A Robber Fly (Almost) from California - Promachus princeps A Robber Fly (Almost) from California - Promachus princeps A Robber Fly (Almost) from California - Promachus princeps A Robber Fly (Almost) from California - Promachus princeps

Moved
Moved from Giant Robber Flies.

 
Robber Fly
I have a friend that is a robber fly, it visits me every morning in California. I took some pictures of it and its the coolest looking picture of a robber fly I ever seen. I never posted on on here before, its not working for me now I don't know what I done wrong.

Promachus
Is the correct genus. And this is either albifacies or princeps and I favor princeps with this coloration. P princeps range is now known to be larger than in the original paper describing it from WA OR and Northern CA. It is supposed to be a much grayer species than albi. Both have the pure white facial hair and princeps is supposed to have clearer wings. They are both fairly variable however.

And, yes, handle the big robbers carefully. If they can inject the finger with their little flesh eating toxin it can hurt, though they are not aggressive otherwise.

 
Thanks Herschel!
Good to have your help and comments. (And glad I got the genus right:-) There are photos of the type specimen for Promachus princeps on this page of the Harvard MCZ website, if that may help determine albifacies vs princeps. I'll move these to the Promachus guide page for now.

Regarding handling big robbers...is there a safe way to hold them? Sometimes it's hard to get a photo and the option of "catch-photograph-and-release" is quite appealing, especially if it can be done without harm to either party :-)

I would
Be a bit more careful if I were you! Those big robbers can deliver a serious bite if you hold them like that!
Greetings

 
Thanks Gerard...
...for your concern and advice. I'll be more careful in the future. Thankfully both Robber and I parted without injury :-)

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