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There is only one species of koala (Phascolarctus Cinereus), and some disagreement about whether there are two or three sub-species, or indeed, whether there are any sub-species at all. According to...
No, there is only one species of koala. Koalas are the only surviving species of the family Phascolarctidae. They are all grey in colour, with southern koalas tending to brown.