Dear Aleksandra, 

Based on morphology, it looks like an agaric in the Coprinus/Coprinopsis group. 

Regards,

Hugo

Thanks for suggestion

Best regards :)

Yes, I agree with both Hugo and Hero.

Best

I think it just could be a Coprinellus, once Coprinus is a coprophilous genus... You must see microscopic structures...

The one growing on the concrete? wall is problabli Coprinus domesticus. The one on the wooden ceiling can be a more aggressive wood-rotting fungus, as Coniophora puteana. You have to put it in the microscope, and open the ceiling to see the whole damage area. Remove all rotten wood, and of course stop water intrussion.

Hi, I agree with Maripaz, Coprinellus domesticus.

This is the definitely Coprinus sp.

I also have observed this fungi in rotten straw/grasses. Within one night, white fruiting body get converted to black one.

Kind regards.

Yes, but occasionally you can find them in a very neglected buildings. It looked amazing.

Kind regards

As always it should be noted that photos can not give a certain determination.

Then in these Genres (Coprinus, Coprinellus, Cprinopsis) will require a complete microscopic card.

The yellowish-rust stain on the wall could come from the typical mushroom mycelium (ozonium) and this points us towards Coprinellus domesticus (Bolton) Vilgalys, Hopple & Jacq. Johnson  [ex Coprinus domesticus. (Bolton) Gray*.

But in literature it grows only on wood or leaves.

Then in C.domesticus often the stipe has a margin (volva-like) that from the picture I don't see.

The shape of the Cap does not seem that  one of Coprinellus xanthothrix (Romagn.) Vilgalys, Hopple & Jacq. Johnson, (ex Coprinus xanthothrix (Romagn) but also reported in the literature as Coprinus domesticus sensu.Lange.

Thanks You.

The plaster in the building was put on the mat of reeds, perhaps they give fungus cellulose nourishment.

Thank you for the hint, I looking theses species in the keys.

If You want to do an useful comparison and see some good microscopic tables, You can go to:

http://www.funghiitaliani.it/index.php?showtopic=17096

Sincerely.

Dear Alexandra,

I`ve seen Coprinellus domesticus under such life conditions, and your photos look like this species, but microscopy is needful for correct identification indeed. Try the key from the book attached

With best regards,

Elena

I think it is a Coprinopsis sp.

David