Here's a question.....
Where are pure thayeri found in the wild?
Does anyone think thayeri interbreed with other species or subspecies???????

There is not an easy answer to that, and I have seen some WC animals from areas that could be called intergrades with thayeri and alterna, plus I have no doubt that many other "odd" populations exist but are not sampled. And I think that thayeri are a population that arose from some convergence anyway and are in that sense a hybrid population of some ancestral mexicana groups. This would in a way explain the great deal of variability found in them, at least to me it does...
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Herp Conservation Unlimited

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