Two closely related species of the genus Piribelba (Oribatida, Damaeidae) are redescribed based on morphology of adults and developmental instars. Redescription of P. rossica (Bulanova-Zachvatkina, 1957) is based on specimens collected in Russia, including specimens identified by Bulanova-Zachvatkina; redescription of P. piriformis (Mihelčič, 1964) is based on specimens collected in Europe, including Mihelčič's types. COX1 sequence barcoding of P. piriformis and P. rossica indicated that they are distinct species, having 12.0% uncorrected p-distances and 13.3% Kimura two-parameter distances (K2P). Based on the morphological and genetical differences, the synonymy of P. rossica and P. piriformis is rejected. A key to known species of Piribelba is provided.