The xiphis on the Nile Mosaic of Palestrina.
A possible xiphis on a mosaic in Pompeii's House of the Physician.
The xiphis (ΞΙΟΙΓ), also spelt xifi, xioig, and xsipig, was an animal depicted on the Nile mosaic of Palestrina, and possibly a mosaic in the House of the Physician in Pompeii.[1] According to Dennis F. Kitchell, its name is nonsensical and has no meaning.[1]
One theory was that the animal was a poorly-drawn elephant, but Paul G. P. Meyboom rejected this and suggested it was a sarkophagos tauros, a "carnivorous buffalo" reported from Ethiopia by Agatharchides. Meyboom suggests that this animal could have been a desert warthog (Phacochoerus aethiopicus). In this interpretation, part of the animals name has been worn away. Alternatively, Meyboom theorised that an animal which he identifies as the warthog or even the sub-Saharan giant forest hog (Hylochoerus meinertzhageni) was known in antiquity under the names of xioig, xiphos, and xiphias.[2]
A more dramatic suggestion is that the xiphis was in fact a living entelodont, a very large, probably dangerous pig-like group of animals known from fossils no later than the Miocene Era.[3]
An image of a very similar animal appears in a "Nilotic scene" on a mosaic in Pompeii's House of the Physician, being attacked by pygmies as it itself devours one. This animal has often been identified as a hippopotamus,[1] and the animals around it as crocodiles. However, the xiphis of the Palestrina mosaic cannot be a hippopotamus, as these animals are accurately depicted elsewhere on the mosaic.