I live in Ceredigion in west Wales, this county is not listed in the dropdown list 'where do you record'. Ceredigion used to be part of the county called Dyfed, but Dyfed is not listed either
Comments
Best site for checking
Charlie Barnes' wonderful Grid Reference Plotter page at https://www.cucaera.co.uk/grp/ is just what you need if unfamiliar with Watsonian VCs.
For recording purposes iRecord uses Watsonian vice-counties. The logic behind this is that the borders are fixed, allowing comparisons over time that don't change if the political borders or names of counties are changed.
Realistically all of the sightings are plotted direct on a map so you don't enter a county or vice county, that bit about where you record is just so that when you sign in it can show you records from your area. I think for you that would be vice county 46 (Cardiganshire).