 Most of the north to about 19° North is regarded as being in the Palearctic, and is largely made up of the Sahara desert and adjacent littoral habitats.South of this is regarded as being in the afrotropical biogeographic realm, which means that species of a predominantly Afotropical distribution dominate the fauna.South of the Sahara is the South Saharan Steppe and Woodlands ecoregion which integrates into the Sahelian Acacia Savanna ecoregion.