Two species of the oribatid mite genus Parapirnodus represent a significant component of the arboreal fauna in canopy habitats in Western Canada, including the canopy of Amabilis fir (Abies amabilis), Western hemlock (Tsuga heterophylla) and Sitka spruce (Picea sitchensis). One of these species, P. coniferinus sp. nov., shows distinct sexual dimorphism, with differences in size of notogastral porose areas. This species also has a larger male spermapositor than the second species, P. hexaporosus sp. nov., which lacks sexual dimorphism. The two species are described and the family placement of Parapirnodus in Scheloribatidae, rather than in Oripodidae, is confirmed based on analysis of adult and immature characters.