However, because they exclusively inhabit wet montane forests above 2,000 m, they are geographically isolated from one another, in much the same way that some species become endemic to particular islands. H. endorobae appears to be endemic to the Kenyan Rift mountains east of Lake Victoria from Mount Elgon to Mount Kenya. H. denniae, on the other hand, is endemic to the Ruwenzori Mountains, along the border between Uganda and the Democratic Republic of the Congo, while H. vulcanorum is found just south of the Equator, in Burundi, Rwanda, and the D.R. Congo.