Weaver's Wave Idaea contiguaria
Wingspan c. 20mm.
A nationally scarce species, being only found in the hillsides of Caernarvonshire and Merionethshire in north-west Wales. It inhabits heather moorland and rests on rocks and walls during the day.
There is one generation, with adults emerging in June and July.
The larvae feed mostly on heather (Calluna), but also on crowberry (Empetrum nigrum) and navelwort (Umbilicus rupestris).