Yellow-Tail Moth (Euproctis similis)
Also known as the Goldtail moth or Swan moth, this is one of 11 species in the moth family 'Lymantrinae', which includes the Vapourer moth and the Black Arches.
It can be found in woodland edge habitats, on scrubby grassland, along hedgerows, and in parks and gardens throughout England and Wales, between May and August. Very occasionally, there may be a second generation.
With an average wingspan of 35-48mms females are larger than males and the tail-like yellow or orange projections on their abdomen are also bigger than their male counterparts. Open or closed the wings are white.
Males on the other hand, have a black or brown spot easily visible when the wings are closed.
Curiously, when sensing fear or when touched, this moth will collapse on its side and feign death.
I know the feeling....

The Yellow-tail, Goldtail Moth or Swan Moth is a moth of the family Lymantriidae. It is distributed throughout Europe.