Unexpected Visitor!

Normally I don't like flying insects but I do like butterflies; though only to look at when outside (not in the house). This little critter flew into our study early this evening:

I didn't mind handling it as I thought it was a butterfly. My husband and I saw this insect (or one of the same species) near a bush early in the day and assumed it was a butterfly, as we only saw it briefly. After searching online to find out what species it was and being unsuccessful I thought I'd look at moth species as well.

It turns out it is not a butterfly - but a Swallow-tailed Moth! Here is a picture of this type of moth:

(link)

The Swallow-tailed Moth (Ourapteryx sambucaria) is one of the largest moths found in the UK. It's been described as 'a large, impressive moth, remarkably butterfly-like' and so it was easy to mistake for a butterfly. Whilst researching, I also found out that this moth is nocturnal, attracted to light and emerges during July - as if we needed any more confirmation!