How about Marrow? Instead of bones she'd be able to produce exoskeleton from her body to be used as armor and weapons, including wings for flight, antennae for increased senses, and venomous stingers. Chitin feels like a fitting name imo. 

I imagine she’d be more of a misunderstood outcast due to her mutations being more visible and “undesirable”. Did you have any set info on this settings version of the Morlocks?