Morphological variability at intra-species level constitutes a critical but often underestimated factor in taxonomic research. In many groups, the range of variation remains insufficiently documented, which may lead to difficulties in species delimitation and correct interpretation of diagnostic traits. This issue is particularly relevant for representatives of the genus Podothrombium (Acariformes: Parasitengona: Podothrombiidae), whose morphological differentiation in natural populations has rarely been analysed. The present study aims to investigate intraspecific morphological variability in peat bog populations of Podothrombium and to evaluate the potential taxonomic implications of the observed variation. We assume that seasonal and habitat factors contribute to the variability of morphological characters of Podothrombium inhabiting peat bogs. The material consisted of terrestrial Parasitengona collected in pitfall traps between 2010 and 2012, from April to October during an arachnological research project. Twenty-one sites located in the Western Sudetes were investigated, all situated on peat bogs differing in type (transitional and raised bogs) and elevation zone (lower montane, upper montane, and subalpine zones). In total, 1,497 individuals of Podothrombium were collected. A subset covering different peat bog types and collection times was selected, prepared, and subjected to detailed morphometric analyses. Overall patterns of morphological variation were explored using principal component analysis (PCA). Three species of Podothrombium were detected in the material based on the structure of dorsal opisthosomal setae. Within each group, usually two subgroups of individuals with different leg lengths were observed, which we attribute to sexual dimorphism. Observed intraspecific morphological variability was influenced by seasonality as well as by environmental parameters, particularly peat bog type and its position within the vegetation zone, suggesting broader than previously assumed intraspecific variability. The findings once again highlight the importance of considering both seasonal and habitat-related factors in morphology-based inference and suggest that environmentally driven variability should be carefully evaluated before drawing conclusions about species boundaries.