Ah, found it! It was on 4th Jan, and William's surname has been mistranscrbed as 'McNulty' (there is an actual William McNulty marriage further down same page), albeit the record is clearly 'McGonagle'. He gave his address at time as Moville, which was in County Donegal and she as Waterside, which was Londonderry.
I've reported his surname error, so hopefully it will be corrected at some stage.