Dark Arches Moth Some Common Blues (in several of the above photos) tend towards "whitelegged-ism" but the blue male White-legged Damselfly looks very different and has totally white legs. Apamea monoglypha

Dark Arches moth Dark Arches moth: wingspan 45-55 mm
Dark Arches moth UK flight time: Jul-Sep
Dark Arches moth
Like a velvet cloak
Dark Arches moth
Dark Arches moth
Dark Arches moth
Dark Arches moth
Dark Arches underwing
Dark Arches moth
The segmented body and underwing