Namibia's endemic mammals include Hartmann's mountain zebra (Equus zebra hartmannae), black-faced impala (Aepyceros melampus petersi), black mongoose (Galerella nigrata) and several rodents. The distribution of endemic mammal species is similar to that of birds (figure 7.22), with most species being broadly associated with the escarpment separating the Namib Desert from higher elevations to the east. However, the majority of endemic mammals occur in southern Namibia, and some species have ranges that extend into similar habitats in northwestern South Africa.

Around 16 species of birds have 90% or more of their global population either entirely within Namibia, or within Namibia and extending into Angola. These species are concentrated in the western half of the country, in the Namib Desert and the belt of mountainous terrain and dry savanna running along the escarpment and immediately inland of it. These areas largely fall within the network of national parks and communal conservancies, where conservation is prioritised.

Hartlaub's spurfowl (Pternistis hartlaubi) is a small francolin found in rocky habitat on the escarpment in northwestern Namibia and southwestern Angola, and farther east towards the Waterberg and the Karstveld around Otavi. The bird is usually found around rocky outcrops and is fairly common within these habitats. Little is known about its ecology. Although the overall low population density and confinement to suitable habitat make this species vulnerable to external influences, it is not classified as threatened.

The dune lark (Calendulauda erythrochlamys) is Namibia's only truly endemic species, with its entire population confined to the dunes of the central Namib. Larks are successful in arid habitats if they are nomadic to some extent, gathering where there is abundant food after rain. Dune larks, however, spend their entire life in the sand dunes, move around very little and make the most of the little shade that is available. Their food of dry seeds is supplemented with insects such as ants and termites, which provide them with sufficient moisture and energy. Such strategies help dune larks live with the extreme heat and aridity of the Namib Desert, where few other bird species can survive.37

Reptile endemism is highest in western Namibia (21 species) partly due to the higher diversity of restricted-range species along the escarpment. Of the 65 endemic species, a third (23 species) are thicktoed geckos (genus Pachydactylus). ). There are several highly localised endemics scattered throughout the Namibian interior and these are generally of greatest conservation concern due to their small distributions, although many are not currently listed as threatened. These localised endemics are often associated with specific substrates or geological features. The escarpment, Karas Mountains, Otavi Mountains and the Namib Desert contain important habitats for localised endemics. Several Namibian endemics were only recently described, and more doubtless await recognition.

Amphibian endemism is highest in central Namibia, in contrast to their diversity which is greatest in the northeast (figure 7.12). Only five species are considered endemic, and three of these are widespread within Namibia. Two species have highly localised distributions and are of greatest conservation concern: the Mapacha grass frog (Ptychadena mapacha), which only occurs in a small patch of the Zambezi Region; and the desert rain frog (Breviceps macrops) which occurs in the coastal southern Namib Desert, and also extends into South Africa.

This map illustrates the probable, general trends of invertebrate endemism. Endemism rates are relatively low in the northeast because the savanna and woodland habitats there extend over vast areas into neighbouring countries. Conversely, endemism rates in the south and west are particularly high, reflecting the arid adaptations of the fauna and the biogeographic history of the region. The Karas Mountains form an endemic hotspot, as is the escarpment in the west, and the winter-rainfall Succulent Karoo Biome in the far southwest. The highest invertebrate endemism rates in Namibia are found in the Namib Desert; in parts of the Central Namib more than 75 per cent of the species found there occur nowhere else in the world.

Many species of scorpion are adapted to arid areas, and this is where most of the 14 species of endemics occur. The highest diversity occurs in the western areas where there is a range of rocky and sandy habitats and a mix of elevations. By contrast, there are fewer endemic species in the eastern half of the country and in the Namib dunes where there is less variety in the substrate and topography.