| Cyprus dwarf hippo Temporal range: Pleistocene to Early Holocene,
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|---|---|
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| Composite mounted skeleton of H. minor | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Hippopotamidae |
| Genus: | Hippopotamus Linnaeus, 1758 |
| Species: | †H. minor
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| Binomial name | |
| †Hippopotamus minor | |
| Synonyms | |
|
Phanourios minor Sondaar and Boekschoten, 1972 | |
The Cyprus dwarf hippopotamus or Cypriot pygmy hippopotamus (Hippopotamus minor or Phanourios minor) is an extinct species of hippopotamus that inhabited the island of Cyprus from the Pleistocene until the early Holocene. The 200-kilogram (440 lb) Cyprus dwarf hippo was roughly the same size as the extant pygmy hippopotamus. Unlike the modern pygmy hippo, the Cyprus dwarf became small through the process of insular dwarfism. H. minor is the smallest hippopotamus of all known insular hippopotamuses.[2] It is estimated to have measured 76 cm (2.5 ft) tall and 121 cm (4.0 ft) long.[3]
Mitochondrial DNA suggests that its closest living relative is the common hippopotamus, (Hippopotamus amphibius) with an estimated divergence between 1.36 to 1.58 million years ago.[4] The ancestor of the Cyprus dwarf hippopotamus is uncertain, but is likely either H. amphibius[4] or the extinct species Hippopotamus antiquus.[5] The timing of the colonisation is uncertain, though the earliest fossils date to around 219-185,000 years ago.[4] At the time of its extinction around 12,000 years ago, the Cyprus dwarf hippo, along with the similarly sized Cyprus dwarf elephant, were the only large mammals native to the islands, and one of only four native terrestrial mammal species, alongside the still living Cypriot mouse and the extinct genet species Genetta plesictoides,[6] and had no natural predators.[7]
Compared to H. amphibius, the muzzle region of the skull is much shorter, and the skull as a whole resembles that of the pygmy hippopotamus.[8] Unlike other species of the genus Hippopotamus, the lower fourth premolar has been lost.[5] The teeth of H. minor are more brachydont (less high crowned) than those of H. amphibius, suggesting that H. minor probably occupied a browsing niche, in contrast to the grazing predominant diet of modern Hippopotamus amphibius, though its diet is likely to have varied in correspondence to glacial cycle-induced climatic changes.[9] Analysis of the limb and hand bones suggests that it was more terrestrial than its living relatives, and capable of moving on the rugged terrain of Cyprus, with changes including the shortening of the distal (closest to foot) part of the legs, and increased robustness of the limb bones.[10][5]
Bones of H. minor are associated with human artifacts at the Aetokremnos rockshelter on the southern coast of Cyprus, dating to approximately 12,000 years Before Present, which is suggested by some authors to provide evidence that the Cyprus dwarf hippo was encountered and driven to extinction by the early human residents of Cyprus.[11][12][13] However, these suggestions have been contested, with an alternative proposal that bones at Aetokremnos accumulated naturally over hundreds of years, with the human occupation of the site after the bones were initially deposited.[14][15]
