Mrs. T from Russia help please. what Kind of mushroom is this? do you need more info about it. thanks......j.k
it's Ms.
If the lower surface had tiny bumps or bristles, it's the Northern tooth fungus,
Climacodon septentrionalis. It often grows from cracks in standing trees and is very recognizable when it does (it's easier to confuse it with other pale polypores when it grows on rotting logs). But it's usually a BIG impressive fungus that takes a few weeks to develop fully.
Inedible because it's tough, leathery and sour. I wish ornithologists or marine biologists also had to deal with everyone always asking if birds of paradise or all those crummy little cetacean species that are only known from a few bloated beached individuals taste good)))
It's commonly included in various red lists because it usually grows on big trees in old, high-value forests (but also because it's recognizable and very easy to spot).
Redlisting obscure, rarely fruiting species, no matter how rare and threatened, that only a dedicated specialist can locate and identify correctly, is a bad idea, so sometimes mycologists include species that are
sort of rare but share the specific habitats (usually primary forests) with the more rare and vulnerable species. Climacodon is a good example.
I have one growing annually on an old birch in a deep ravine near my garden. It's not uncommon in our old birch forests.
https://mycology.su/climacodon-septentrionalis.html some more pictures here