No, it’s not Mothra, but damned if it isn’t his cousin.
I was at the Takoma Metro station this evening (just outside the DC borders, for all you non-local lepidopterists) and came upon what may have been the biggest moth I’ve ever seen, trying to camouflage itself against a concrete pylon holding up the station roof. The body was about two inches long, with the upper wings extending downward and outward beyond the body for about another half-inch to inch. The lower edge of the wings lined up with the outside of the body so that the wings didn’t actually cover it. The wings themselves were a mottled brown, with a prominent set of light and dark brown stripes running along the lower edge (picture the moth’s head pointing upwards at the apex of a triangle; the stripes ran roughly along the base).
There was a prominent stripe down the back of the abdomen, and on the crest of the head was something that looked very much like a skull, or a human face, with dark black curves framing it so that it looked a little like someone peering out from under a large, heavy hood.
A fairly in-depth look at several on-line resources make me think it’s some sort of sphinx moth, since the shape of the body and size most closely resembled the family Sphingiidae. But I couldn’t find an exact picture of the beastie so I don’t know what I was looking at.
LepiDopers? What you got?