This rat is recorded from the Gotel Mountains of southeastern Nigeria. A 1992 paper called the specimens Praomys hartwigi obscurus and left unresolved whether they were a species or subspecies.
In the series called Praomys hartwigi obscurus in 1992, adults had dusky brown backs and juveniles were slate gray. The long, soft dorsal fur was about 13–14 mm; gray ventral hairs had short creamy tips.
The 38 specimens labelled Praomys hartwigi obscurus came from fern-grassland, forest, streams in forest, gallery forest, and forest swamp.
An extinction-risk assessment has not been added yet.