What ID of yours are you most proud of?

I am no ornithologist. When I see a bird, I’m content to call it a bird, though I’ve IDed a heron and macaws.

A few days ago, I came across a feather. I IDed it as Numididae, which someone soon specified. Out of Africa, it could hardly be anything but N. meleagris.

How did I know? My landlady has guineas, and I recognized the spots.