Silky Wave Idaea dilutaria
Wingspan 20-22 mm.
A very local species, occurring in only one or two places in Wales, and occasionally in England.
The adult is quite plain in appearance, but as the English name suggests, has a silky lustre to the wing surface.
It inhabits limestone cliffs and downs, where there are low bushes, and the larvae feed on common rock-rose (Helianthemum mummularium).
The moths fly from dusk into the night, during July.