The variation shown in the pictures in the Waring, Townsend & Lewington field guide can be a bit misleading if the text is ignored. My experience (and most years I get 100+ in the garden) is that locally our specimens show very little variation and they all look like the left hand example of the four shown in the book (pale sandy grey background with fine black speckling). The wing-tip also gives the appearance of being slightly hooked when at rest, which is more akin to Clouded Drab than Common Quaker. You'll know when you've caught one!
I'm afraid Steve and Xander's presumed Powdered Quaker and tatty unknown shown below are both Common Quaker.
Update: I should perhaps also have mentioned that last night's garden catch here comprised a reasonable 20 species despite indifferent weather although Epinotia immundana, White-spotted Pug, Common Wave & Pale Tussock were the only ones new for the year. The smelly sexton beetle Nicrophorus humator has been visiting the trap regularly over the past two or three weeks but last night I was pleased to get an example of the massive water beetle Dytiscus marginalis (the Great Diving Beetle). They're powerful flyers and you haven't lived until you've been hit on the back by one of these while standing by a light trap!
|Common & Powdered Quakers|
|Dytiscus marginalis, Westcott 27th April|