What field do I put ap (son of) or verch (daughter of) for a Welsh name? In the name field or the surname field? I've seen both done in my pedigree. Thanks
One FamilySearch page you might wish to look at is found at https://www.familysearch.org/wiki/en/Wales_Personal_Names. Whilst not giving any direct instruction, I believe the strong suggestion is that they should be added to the surname (last name) field. If "ap Robert" is now recorded as the surname "Probert" it follows that it is far more logical to treat the former as a last name, too.
Not much help from me - I am certain that exactly this topic for Welsh names was discussed in the old GetSatisfaction forum but I can't find it in here, even though everything was supposed to have been copied over. I tried searching on both "ferch" and "verch" - nothing helpful.
Being logical about it, which may not be sensible, the patronymics for Scandinavian names get put into the "surname" item - thus (hope this makes sense) Sven the son of Olaf (in descriptive English) would be entered as Sven Olafson, with Olafson in the surname. Surely the Welsh should follow the same route, thus "Harry ap Tudur" with "ap Tudur" in the surname.
But that's me being logical - if you don't get a definitve reply, I would suggest that one good thing to do would be to see what the Welsh indexing projects do - after all, it's going to make more sense if a search tries to match the surname on a profile with the surname in an index, which isn't going to happen if the "ap" and "ferch" / "verch" are in different places.
I might add that at least one FSFT contributor of Welsh profiles won't put anything into the surname!