My great-grandfather was William McTeague, from Malherafelt, Co Derry, Ireland. He immigrated to Glasgow and married Catherine Convery who was from Northern Ireland too. I have a spreadsheet from PRONI that lists McTeague baptism from the area. Someone typed out this information from the Microfiche. There are a number of parishes mentioned.
I visited a graveyard in Ahasgaskin - there were McTeagues there.
Also, as a matter of interest, William's name got changed to Montague - I think it started as a clerical error in regard to public housing. Then when the children went to school, although they were baptized "McTeague", they were registered in school as "Montague". And, that is how my father got his last name... now my last name. But, I should have been a McTeague.
Lynn