https://doi.org/10.1080/00275514.2017.1405215
https://doi.org/10.1111/j.1756-1051.1982.tb01437.x

Rigidoporus is not maintainable as a single genus. Rigidoporus s. str. is congeneric with Oxyporus, and a good chunk of Rigidoporus belongs in Physisporinus.