Red bearded dragons are a specific genetic "morph" of the bearded dragon - not a different species.
It's very much like you have different color versions in dogs, cats, hamsters and so on, but they're all the same species.
Besides being called "red bearded dragons", some of these are simply referred to as "high red" or "desert phase" as herpetologists believe
this color morph has come about in the desert populations of
Australian bearded dragons to help camoflage against the reddish sand found there.
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