Hi Carl, Please note I an no expert,but have given your query some thought.I live in New Zealand & it looked similar to Maori place names,but havefound no surnames as such. In County Mayo I found an entry for Michael O'Horo m. to Mary Brady 27/5/1876.I think it was probably O'Hora, but has been written as it sounded,phonetically.(If someone rolled their "O" it could have been spelt "Ho"Horo at some stage.Also part Roscommomon ended up in Mayo or vice versa. My gggrandparents have 3 different spellings of their surnames on various documents. However, if you Googlesurname Horoho a lot of info comes up which should be helpful.It certainly looks well worthwhile. Kind Regards, Rex Neary.