Coralline coloured Mithrax crab?

[VFX]

I just set up a new tank & found a hitchhiker.

It looks just like a Mithrax crab but it's similar colour to coralline.

I've had reddish & also green Mithrax crabs before but not seen one this colour.

Does anyone know if coralline coloured Mitrax crabs exist? or is it another kind of crab?

Most important question should I get rid? (I never really like my Mithrax crabs as one of them destroyed some nice acros I had)

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EDIT.

Nope it's not a coralline covered Emerald!

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