The liverwort Harpanthus drummondii (Taylor) Grolle (Geocalycaceae, Jungermanniopsida) is known mostly from temperate regions of eastern North America where it is restricted to dead wood in forests. Recently, the species was discovered in the boreal forest of west-central Canada, demonstrating a substantial disjunction from the next closest known occurrence. A distribution map is provided along with features that distinguish it from the closely related H. scutatus (F.Weber & D.Mohr) Spruce.