Based upon location, I decided to check below images at several sites. Since the forewing is partially behind the hindwing the cell bar can not be checked to determine if broken, as in Hackberry, or intact, as in Empress Leilia. The below hindwings of Hackberry and Empress Leilia Emperors are essentially the same. Except I have noted that the basal vertical column in the cell is either broken and misaligned or completely separated whereas the same column in the hindwing of Empress Leilia is either unbroken or fractured but still aligned. This specimen appears to be Empress Leilia based upon the appearance of the HW basal cell column. A similar specimen is located at http://butterfliesofamerica.com/asterocampa_leilia_live1.htm
Since I am now stir crazy, please let me know what you think of this review.

Yeah, Empress Leilia is certainly a good bet. That genus, Asterocampa can all be very similar looking between Empress Leilia, Hackberry and Tawny Emperor. For some reason this just initially struck me as Hackberry, but Empress Leillia is probably more common down there than Hackberry. You are probably correct. I have another shot of an Empress Leilia on another website at: http://www.inaturalist.org/observations/194956 which shows the underwing. I'll bet you are right, Cliff. Good sleuthing!

Your underwing shots of Hackberry and Empress Leilia show clearly the difference in the basal HW vertical column pattern. What excellent images.
I've been buggin for two years and really appreciate great images and photography. Live and in their environment makes it a real challenge.