Common Wainscots

I am slightly concerned about the status of Common Wainscot in Glamorgan. I've had a few people record them over the past couple of years, and I tend to get suspicious when they record Common but not Smoky, which is by far the commoner species in the county, at least in the east. Can I ask that if you catch what you believe to be Common, check the hindwing (a gentle flick with a piece of grass is usually sufficient), and post a photograph if you are happy that the hindwings are white. It might be commoner than I think, and I am aware that this post smacks of "it doesn't exist if I've not seen it", but with only three records in 2016 in MapMate we need to be careful that we are getting them right when they are seen. Dave