Is extreme nail biting and picking skin around nails a form of ocd? does this warrent a psychiatric evaluation for other conditions as well?

Skin picking: Skin picking and nail biting are body focused repetitive behaviors http://tinyurl.com/l89d9vt that are more common in families with ocd. In the dsm5 (the most recent version of the mental health diagnostic manual) this has its own section, called excoriation (skin-picking) disorder. This is within the chapter on ocd, as it's related but not subsumed within ocd. http://tinyurl.com/lq8ly29.

In DSMV yes: Those are now categorized in dsmv as ocd spectrum disorders. I do not think that a psychiatric evaluation is warranted unless there is behavior indicating the presence of another condition. There is one study of children in shariz iraq that showed that the nail biters were somewhat less pro social, had higher rates of parents with the condition, but no specific emotional difficulties correlated.