Hypsizygus ulmarius

Hypsizygus ulmarius, also known as the elm oyster mushroom and less commonly as the elm leech, is a species of fungus. It has often been confused with oyster mushrooms of the genus Pleurotus, but can be distinguished because its gills are either not decurrent or only shallowly decurrent. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/