Bay polypore (Royoporus badius)

This one stumped me. I watched as it began fruiting on a large maple limb that looks as if it’s been down for a long time. The iNaturalist bot was suggesting they might be oysters, but there were no gills so I figured it was some sort of polypore.

Bay polypore shortly after fruiting
I decided to wait a few days and keep an eye on it. This photo was taken 4 days after the one above, and when I fed it to the iNaturalist bot this time it suggested bay polypore. Bingo (or at least bingo based on my limited knowledge of mycology).
Underside of bay polypore, 4 days later. Badius derives from the Latin root badi, meaning reddish brown. As is visible above, the stipe is a dark color, contributing to the other common names “”black footed polypore” or “black leg ploypore.”
In this earlier shot, the stipe hasn’t darkened yet.