Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
robber fly - Efferia - Efferia rapax - male

robber fly - Efferia - Efferia rapax - Male
Southwestern Research Station of the AMNH, 5 mi W of Portal, Cochise County, Arizona, USA
August 29, 2006

Moved from Efferia rapax.

Moved from Efferia. Based upon Herschel's report of Dr Fisher's ID.
On another note, Dr Ascher, we don't know if you considered becoming a contributing editor here at BugGuide. That would allow you to move images around in the guide instead of being restricted to making comments. You might find it easier to tag and move images to the correct guidepage than to take the time to write a separate comment for each one. Especially since images can be tagged and moved in batches. You may have noticed Jeff Hollenbeck doing this with spiders.

There are currently many bee images in the guide here not yet moved to species pages. One of the reasons is that unless we see a comment from you confirming an ID, we don't know enough to know if it is correctly identified, or if the image really doesn't show enough to make it valuable in the guide and it should instead be frassed.

We are happy and thankful to learn from all that you do here at BugGuide and are not asking that you do more, but rather didn't know whether you knew that there were other options. You can become an editor simply by emailing John VanDyk here at Iowa. We're certain he would be happy to offer you that position.

thanks for the offer and helpful information
I'll follow up when I have time...soon I hope

What a superb image! I hope that you continue showing us your photos in addition to all the great help that you have provided us.

Can't see the wing veins but it has the appearance of a member of the Pogonioefferia subgroup in this genus. With the high quality shot I may be able to narrow it down with Wilson's key at home. Dr. Fisher may know it from the extensive silvering on the terminal abdomen.

Efferia again
Tried to get it to a Straminea group species or a Pogonias group. Could not quite make the genitals and coloration fit perfectly. I cannot see the wing veins but I can't imagine it isn't one of these two groups from overall appearance. Dr. Fisher may know it by sight in the SW. Will have him take a look.

thanks for looking into the ID
I realize this is a large and difficult group

Dr. Fisher knew it on sight and it was in the Staminea group. E. rapax. Apparently characteristic AZ fly. I could not see the bristles on the scutellum were yellow. Look black.

Will be a new species page.

staminea key error
Thirteen years later, but in case anyone stumbles across this and is wondering...
Herschel's comment about the scutellar bristles is because of couplet 8 in the key to the staminea group in Wilcox 1966. That couplet is bad and should be ignored-- rapax usually has black bristles despite how it keys out there, and staminea often has a mix of black and yellow.