Here are some of the forms of the surname used and seen on gravestones:

Llwchwr, Lwghor, Lochour, Loughor, Loughour, Llougher, Lougher.

Also in old documents at different periods:

Lloghoure, Lloughour, Lchor, Loughor, Loughour, Locher, Llougher, Loghor, Lwghor and Lougher.

Even the King of Glamorgan couldnt make up his mind in a Grant to Llandaff he used: Luchur, Lychur, Luchue.