Irpex is a genus of resupinate fungi in the family Meruliaceae. Species produce fruit bodies that grow as a crust on the surface of dead hardwoods. The crust features an irpicioid spore-bearing surface (for which the genus is named), 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.