I think Carapace itself has a certain ring to it, also Nodule and Callosity.
Chicane for a girl—(motor racing term)‘a set of tight flowing curves’ What better name for a girl?
For a girl: Vibrissa
For a boy: Rigor
Grease
Is the word
is the word
is the word
charmingly this could do for a boy or a girl!
Naming your kid Chitin would be a good way to see how tough he actually is…
For a girl: Hegemony.
“Well, we wanted to call you Fascism but that sounded like a boy’s name” 
Only if the family is Jewish. 
I like Arrhythmia as a girl’s name. Sure, it’s a little tough to spell, but it just rolls off the tongue. Just like my second-favorite, Anorexia.