Skin condition worry

[Slave2Magic]

My mare has small black specks in her coat near her flank. The hair looks rubbed. Someone suggested mites? If so what do you treat it with. Or any other ideas welcome.

 

[piebaldsparkle]

Is she itchy?

 

[Slave2Magic]

I haven't seen her itching but her flank looks as if she may have been rubbing it. So far I've only washed it with hibiscrub until I find out what the cause is.