Rileyanov. gen. (Coelomycetes) is characterized by thick-walled plectenchymatous pycnidia, hypha-like, branched conidiophores, and holoblastic, distoseptate conidia with a simple apical appendage produced holoblastically from the inner wall. A single species,R. piceae, is described fromPicea sitchensis(Bong.) Carr. in coastal British Columbia, Canada.