LOL. Colour Forms? I have the opinion that tarantulas might have some colour variation but I wouldn't call them "colour forms". In some species there is some natural colour variation, like snakes where you get blue and green Rhinoceros Rat Snakes or where you get different colours of Mice or Rats. They aren't anything special, it's just how it is. I agree though that there is a lot of Hybridizing going on with P. cancerides which could explain the colour variation.
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