PCR was used to amplify ribosomal internal transcribed spacer and 5·8 S DNA from type material of Rhizopogon colossus var. colossus, R. hawkerae, R. parksii, R. reticulatus and R. villosulus plus a number of collections belonging to the same section (Sect. Villosuli). Different restriction enzymes were used to digest these amplified rDNAs to find polymorphisms useful in identification. On the basis of these studies and our previous morphological observations, the conclusion is that the names proposed by Smith & Zeller for collections studied, as well as R. reticulatus, represent only one species, R. villosulus.