Variability in local Single-dotted Waves

This is just a short post in response to the recent query by Mark Griffiths on the identity of a small geometer moth thought to be an odd Treble Brown Spot.  I trap a lot of Treble Brown Spots and also Single-dotted Waves, which is what I think the moth is.  Treble Brown Spots are invariably marked alike, certainly in my garden, but Single-dotted Waves show quite a bit of variability in intensity of markings.  In addition, Treble Brown Spot is more of a June moth, while Single-dotted Wave is more  a July/August moth though there is some cross over.  Photos below of a typical Treble Brown Spot and the variability of Single-dotted Wave, including a particularly dark example.

Treble Brown Spot

Single-dotted Wave - worn but lightly marked

Single-dotted Wave - slightly darker

Single-dotted Wave - darker still

Single-dotted Wave - unusually dark

Hope this is of some interest.

Adam Bassett
Marlow Bottom