Bitis xeropaga, commonly known as the desert mountain adder or Lüderitz dwarf viper, is a viper species found in southern Namibia and northwestern Cape Province in South Africa. Like all other vipers, it is venomous. No subspecies are currently recognized.
Adults average total length (body + tail), with a maximum total length of for a female.
Northwestern Cape Province in South Africa and the arid mountains of the lower Orange River basin, north into southern Namibia and Great Namaqualand as far as Aus is the range for this snake.
The type locality given is "Dreigratberg on north bank of Orange River, Lüderitz district, South West Africa [Namibia] (16ð52' E, 28ð05' S, alt. about 300 m [980 ft])".