This species is known from northern, and perhaps western, Myanmar (Grubb, 2005). The range of C. rubidus is not well known, partly because of confusion with another red serow form in adjacent territories to the west in Assam and Bangladesh, and the fact that all serows can show varying amounts of red and black colouration. True rubidus specimens have black hair base rather than white. Records and specimens from Kachin state in the north of Myanmar are clearly this species. Other localities reported include the Upper Chindwin, Ararakan Hill Tracts and limestone hills in the upper Salween. Without accompanying specimens these records are less certain. The species may overlap in some locations with C. milneedwardsii which extends through most of the Shan States and Pegu (Bago) Yoma at least as far west as the Ayeyarwady river. The type locality is from the "Arakan Hills", however, many of the type localities from that time period are wrong and this may be one of them. Little survey work has been in the region of the type locality.