Pleurotus fossulatus

About

Pleurotus nebrodensis, commonly known as funcia di basilicu "fungus of basilisk" or carduncieddu di macchia "macchia carduncieddu(?)", is a fungus that was declared by the IUCN as critically endangered in 2006. This fungus only grows on limestone in northern Sicily in association with the common basilisk, Prangos ferulacea. The characteristics of the mushroom are its creamy white to yellow colour, its diameter of between 5 and 20 centimeters, its extremely angled gills, and the breaking apart of the cap surface at maturity.

Summary from Wikipedia