This is one of those specimens that might be Schizura errucata. Is there some tried and true way to separate the two? Sometimes errucata has some green in the ruff, and I think that is pretty diagnostic. Osually the legs of Aon are more prominently banded than seen in Schizura, which does also have banded legs. These gray specimens are tough for me, and I see lots of them at my site. Usually Aon has a much more prominent black transverse line across the anterior area of ruff--some errucata don't have any--this one is in between the two. Maybe this is something totally different?