Wholly engrailed (except not...see update at end of post)

We have silver birch trees round about and so we also have the Engrailed and Small Engrailed moths, whose caterpillars live on birch and sallow leaves. I'm relieved to read that even experts have difficulty in telling these two moths apart and some believe that they are actually one species. (Uh-oh. See update at end of post...)

After screwing my eyes up and holding the picture every which way, I think that this one is a Small Engrailed. Actually there were two, in another well-filled trap this morning. The one at the top of the post posed placidly with its wings out, showing a pattern which makes excellent camouflage on most tree trunks.

The other one was extremely frisky and only briefly paused in the long grass before fluttering away. Flutter is the right word for these delicate, relatively large-winged moths, rather than the US drone-style approach favoured by their chunkier, fat-bodied colleagues such as the yellow underwings or the Dark Arches. Their beautiful antennae help them in flight and I have zoomed in on one. I wish humans had antennae. Maybe evolution will given them to us, one day.

Update: Oh dear. All the above applies, except the moth is a Mottled Beauty. Many thanks to Ben (see Comments) and also Charlie Fletcher who popped me an email (with a consoling smiley). It's a Mottled Beauty. Sorry. They're all very similar to my ageing eyes, although look how much more varied Ben's is, left, on the pic from the Flickr link which he gives in his comment. Anyway we've got it right now. The MB is a voracious fan of Silver Birch but has an appetite almost as catholic as my own. According to Waring, Townend and Lewington, its caterpillars have been found contentedly living on oak, ash, blackthorn (of which we have a hedge), hawthorn, barberry, broom, bilberry (hooray - and see this piece on the Guardian's Northerner), heather. bramble, traveller's joy, honeysuckle, juniper, Norway spruce, Lawson cypress, Japanese red cedar, western hemlock spruce, angelica and St John's wort. Goodness.)