Excellent--this has to be the most bizarre beetle I've ever seen--the elytra are reduced to those little scale-like things, correct(?), and we are seeing the hind wings, which are membranous of course, but elongated and held along the abodmen like those of a wasp or fly. This looks to be a mimic of hymenoptera--fasicnating!

Seems like somebody should be able to recognize this--the form is so distinctive. Of what we have in the guide so far for this family, Rhipiphorus has those shortened elytra, compare:

Which you probably suspect already, Joe, since you commented there. That poster (Noah) mentions a 1951 paper on the family for California--I'll leave a note.

Definitely a Rhipiphorus (I've heard Ripiphorus is the correct/modern spelling?) sp.... nice find! I can't make a call on the species without a better view of the antennae and tarsal claws, but if you'd like to try to key it out, here's the key for the Rhipiphoridae of California:

http://essig.berkeley.edu/CIS/cis01_3.pdf

Having perused the key I came to R. vierecki female. But a couple places in the key where hard to tell from the photos. So I wouldn't go making any pages for this yet.

From the new photos, I think I can make out 11 antennal segments. R. vierecki seems like a likely candidate.

Noah, thanks again with your help. A simple photographer, I'm lousy with keys as I have no entomological vocabulary and iffy eyesight.

I've added a couple more photos - bottom row here - and do have others if there is some specific area of interest.