Currently has no common name; "dark-waved angle" is a suggestion. Found on wall of community centre, this species has a western North America distribution. I've emailed Don Lafontaine asking about its status in Ontario.
Of the 3 pinned adult images linked to in the Guide, I think the last one looks closest to this specimen.

Update: ID confirmed by Don Lafontaine. Apparently this is the second Ontario record; Don Sutherland of NHIC says the first record was a specimen collected by Alan Wormington at Point Pelee on 15 June 1994.