Very dried out, hard and brittle. Growing on a fallen tulip poplar across a stream, which also had winter oyster mushrooms (pleurotus) growing on it.

The closest looking match in the iNaturalist auto ID suggestions was hairy oyster, but looking at other panus species photos I definitely can't tell them apart. Actually I'm confused whether lecomtei and rudis are different species or not - I'll leave it to the people who actually know about mushrooms to figure out.