I was driving along and thought I have just seen Masterwort, as I hadn't seen it in Wales before I turned around to make sure my ID was correct! It was! Looking up on the BSBI DDb database I was surprised to see there haven't been any records for Masterwort in Wales for over 70 years. This patch was on the roadside between Bala and Trawsfyndd, VC48 Merioneth. It should be in flower in about a week.