There was a Timothy McCarthy in Lahanaght in Griffith's Valuation, and prior to that an Andrew McCarthy in the Tithe Applotment Books.
These names are very similar to other McCarthys in the general area. For example, a Jane McCarthy baptized 15-Jun-1822 to Andrew McCarthy Sowney and Ellen Hegarty in Lissane Upper. Until evidence indicates otherwise, I think this Andrew McCarthy was my ggg-grandfather's brother.
Given the patchiness and inconsistency in the availability of Irish records, I would recommend an autosomal (admixture) DNA test for anybody uncertain of their neighborhood origins. Your DNA matches might point you in a fruitful direction. I know where my mother and her parents were from in the Skibbereen area but through the test I am discovering connections we would never have known about otherwise.