The taxonomy of the staphylinid genus Mocyta was explored using molecular markers, in addition to a thorough investigation of the published literature regarding this genus and its proposed morphospecies. The aim was to test if the recognized morphospecies differ genetically, and if popular species delimitation methods can be used to delineate these species. Furthermore, the most widespread and also most common species in Norway, Mocyta fungi, was examined in more detail to test if any geographic patterns are reflected in the genetic variation, and if this variation correlates with ecological preferences. This study also aimed to explore if the parthenogenetic populations of M. fungi are restricted geographically. In total, 111 Mocyta specimens, representing 12 morphospecies from 17 countries, were included in the analyses. Both maximum likelihood and Bayesian inference were employed on two PCR amplified molecular markers (the mitochondrial cytochrome oxidase subunit 1 and the internal transcribed spacer 2 of the nuclear ribosomal gene cluster) to investigate the phylogenetic relationship of these morphospecies. In addition, calculations of mean intra- and interspecific genetic distances were used to delimit species. Online service for delimiting species using Bayesian implementation of the PTP model (bPTP) was also applied. Haplotype networks were used to investigate the genetic variation among specimens of M. fungi. The maximum likelihood and Bayesian inference analyses grouped the morphospecies together in well-supported clades, but the species delimitation methods applied failed to confirm this. The bPTP method estimated many species, exceeding the number of morphospecies, but the supports for these were generally low. There were no evident geographic patterns reflected in the genetic variation of M. fungi, nor any correlation between genetic variation and ecological preferences. Biased representation of specimens from different countries made it impossible to confidently compare the genetic variation between specimens from Norwegian populations and specimens from populations elsewhere. Even though all 33 specimens of M. fungi were females, the parthenogenetic populations of M. fungi could not be examined outside Norway because too few non-Norwegian specimens were included.