Being new to the area I am not sure how common this species is on the Llyn, but in my home area of Calderdale in West Yorkshire it seems to be species now spreading throughout the area. The only specimen of Ringlet I have seen so far was on Nefyn beach of all places on 14th July this year. Ringlets are a species of Grassland usually not beaches, so I assume it had been blown down from the grassy areas above the beach. Its a widespread on damp grassland throughout Britain and Ireland. Dark brown butterfly. Underwing has distinctive eyespots: white centre, black inner ring and outer yellow ring. Similar to male Meadow Brown.
Thanks to Winston and Charly for the loan of the images