Irpex

About

Irpex is a genus of corticioid fungi in the order Polyporales. Species produce fruit bodies that grow as a crust on the surface of dead hardwoods. The crust features an irpicioid spore-bearing surface, meaning it has irregular and flattened teeth. Irpex is distinguished from the similar genera Junghuhnia and Steccherinum by the simple septa found in the generative hyphae.

Summary from Wikipedia