The southern white rhinoceros or southern white rhino (Ceratotherium simum simum) is one of the two subspecies of the white rhinoceros (the other being the much rarer northern white rhinoceros). It is the most common and widespread subspecies of rhinoceros.
The southern white rhinoceros is the nominate subspecies; it was given the scientific name Ceratotherium simum simum by the English explorer William John Burchell in the 1810s. The subspecies is also known as Burchell's rhinoceros (Ceratotherium simum burchellii) after Burchell and Oswell's rhinoceros (Ceratotherium simum oswellii) after William Cotton Oswell, respectively. However, these are considered synonyms of its original scientific name.
Ceratotherium simum kiaboaba (or Rhinoceros kiaboaba), also known as straight-horned rhinoceros, was proposed as a different subspecies (or species) found near Lake Ngami and north of the Kalahari desert. However, it is now considered part of the southern white rhinoceros.
Following the phylogenetic species concept, research in 2010 suggested the southern and northern white rhinoceros may be different species, rather than subspecies, in which case the correct scientific name for the northern subspecies is Ceratotherium cottoni and the southern subspecies should be known as simply Ceratotherium simum. Distinct morphological and genetic differences suggest the two proposed species have been separated for at least a million years.
