Looks like it's my day to be difficult. No matter how hard I try, I just can't make this into Texola elada. They are very common here - I've seen gazzilions and none that looked like this (even at the exact same locality). For one thing, this guy was 1/3 larger than any T. elada I've ever seen. Secondly, its front wing margin is straighter than the more rounded T. elada's. It just doesn't look like the common T. elada I'm used to seeing. Just posted a couple from the nearby Pima Canyon that I took a couple years ago. Only reason I photographed the one in question, is that it looked like theona or arachne. Check out my recent posts Just looked at bugguide's images and I think there is at least one other misidentified among them. I'd appreciate it if you'd move mine back to unknown group or frass, since I think someone needs to go over these with a "fine-toothed comb." On the other hand, I won't pitch a hissy if its left here.

I looked at this thing long and hard several times, because it is so light, and it looks pretty odd. The shape looked off too, but the front left wing looks more pointed with a straighter outer edge because a bit of the wing is missing. The light color is partly (I think) because it's a somewhat faded worn individual. The pattern is that of Texola elada, and it matches nothing else. Particularly look at the arrangement of markings in the middle of both wings. The arrangement and shape of markings on the hind wing is like no other species. The closest is Dymasia dymas, but the markings are of somewhat different shape. It definitely is not anything in the Chlosyne group, nor Poladryas. Too bad we don't have the underside to look at.

Females are often a lot larger than males, with somewhat wider wings (your's looks female). I've caught females that were double the size of the males mating with them. One thing about Checkerspots, is that most species are highly variable, and sometimes there are some really weird looking ones. In this species they can range from almost completely black to almost completely orange above.

As far as I can tell, all of the ones shown on BugGuide are correct.

Here are a couple of places to see a bit of the variation:
Butterflies of Southeastern Arizona
Butterflies of America
Butterflies of America

for the input David. I've seen Theona in S. TX and it just doesn't fit the bill, but then...

the input Ron. I think this little one was on a road trip - you probably noticed that it's a bit worn. I favor Arachne myself, primarily because of the pattern on the upper hind wings. The habitat is upper Sonoran, with lots of Mesquite, Palo Verde, Creosote, and Cholla. Very few flowering plants this dry time of year - definitely not paintbrush here, nor beardtongues. And the Tucson Mts. haven't seen a meadow in over 1,000 years, so yah, I think this one was from somewheres else, just out seeing the west.