The Del Carmen whitetail was described in 1940 by Goldman and Kellog based on a type specimen collected in Botellas Canyon in Coahuila several years before (Goldman and Kellog, 1940, Proc. Biol. Soc. Washington, 58:31, June 28). I doubt that anyone except SCI would argue that they are not the same as Coues whitetails. They were largely extirpated from the Big Bend area of Texas by that time and current populations in the U.S may very well have originated from deer trucked in from Arizona. The range described in Hall (1981) extends into southwest Coahuila and adjacent Chihuahua east of the Sierra Madre Occidental. A recent thesis by a graduate student at Northern Arizona University examinedDNA analyses of Coues deer range wide. I contributed over thirty samples to this study from the Animas Mountains of southwestern New Mexico. At that time, he indicated that he hoped to include samples from del Carmen whitetails in the Big Bend of Texas, but the thesis that I saw did not include any samples from that region (as I recall). Unfortunately, I cannot lay my hands on the copy that I have right now. I may have loaned to someone to read...
With respect to desert mule deer and Rocky Mountain mule deer, Jim Heffelfinger (Hefflefinger, 2006, pp. 7-11) asserts that "...these subspecies are nothing more than points along a natural gradient of body size that is common in species whose distribution covers a wide latitudinal range." At the time that Jim was working on his book (Deer of the Southwest, Texas A&M University Press, 2006), he indicated to me that DNA analyses had been done on both "Rocky Mountain mule deer" and "desert mule deer", but no citation for any such work is included in the book. There is also a discussion of the "burro deer" as well as geographically isolate populations of mule deer on islands in the Sea of Cortez.
