Aaron,
I suspected a cross at first, but just wanted to see pics to make sure. I also forgot about the Juno Rd. aneries and I did not know Shannon had adult mexmex X alterna crosses. I would like to see them if they are still around.
As for the purity of our mexicana complex I can state that our Greeri and Mex mex still are "pure" by appearance. I have done some research about Louie Porras' finds and have seen many pictures of his founding stock(s). Our Greeri and Mexmex resemble these founding animals greatly. As for Thayeri, we have line bred this ssp. to the point were all like "good" genes have produced brighter, cleaner offspring. There are some colorful Thayeri in the wild but most are often drab in appearance. We breed by selecting two of the nicest and producing even nicer offspring (line breeding). We are propagating things that would never happen in the wild. Generations of doing this has produced the awesome colors in Mexicana we see today. On the other hand, you will have to trust your breeder is telling you the truth, but this is with any snake not just Mexicana ssp. The only reason I did this research is because I had some doubts myself after someone posted on the Kingsnake Forum that "we do not know what any of our Mexicana Kingsnakes really look like or if they are from where they are said to be from." I guess this guy just did not know because there are many out there that do know what we have is the real thing,
-John Lassiter-