I suspected it was something new to the guide simply because I spent an inordinate amount of time through the Psylloidea and was unable to match it. Thank you Chris!

Hodkinson's key takes this one easily to A. acaciae / inermis / californica, but it's difficult to tell the key characters beyond that. But californica has a different wing pattern (just a transverse band along the apex) and is known from only California, and wing shape/venation of acaciae is slightly different. Additionally, acaciae is slightly smaller (thanks for the ruler shot!) and has pretty different female genitalia. Due to all of these things, I'd say what you've got here is A. inermis, which is known from Texas to Southern California and into Mexico, on Prosopis glandulosa.

Despite being a very small genus (just 9 spp. worldwide) I've found it to be a very difficult genus to ID to species, so many thanks for the great photo series to be able to make it possible.

motivated me to look for any critter in the superfamily Psylloidea. Thank you Chris for sharing your expertise with the BG community.
In the next weeks, I am hoping to find a male Kuwayama medicaginis and provide a better lateral view before I move to Nogales, AZ.

I always hope my enthusiasm for these critters can inspire others to pay more attention to them. Thank you for looking for and photographing them, all of your contributions have been wonderful additions to bugguide and beyond.

Best of luck on your hunt for Kuwayama medicaginis. I remember about this time last year you were finding quite a few of them, but I know it's tricky to find a species that doesn't have a definitive host association.

May you also find luck in Arizona, I've seen lots of interesting bugs submitted from that area so I think you'll have no shortage of cool finds. Many interesing psyllids there too, including 5 (!) mostly Triozid genera not yet represented in the guide (1, 2, 3, 4, 5). Lots of potential in that region to make new and exciting contributions!