The Plain Wave is very similar to the much commoner Riband Wave. I check all the Riband Waves I catch in the garden and have never recorded Plain Wave with any certainty but last night I caught this individual which lacks the indentation on the the leading edge of Riband Wave which is so characteristic of that species. I've overlain a Riband Wave against half of the Plain Wave to show the difference. Nationally the Plain Wave is described as local and thinly distributed which is probably a fair description of its status in Derbyshire.
Spent the evening around the Via Gellia but it was cool around 9 Centigrade by 10:30pm but picked up a few moths new for the year. Plain Wave is scare, I only trap one or two per year more expected was Shaded Broad-bar but also added Argyresthia brockeella and Mompha raschkiella.