Xenocyon ("strange dog") is an extinct group of canids, either considered a distinct genus[2] or a subgenus of Canis.

[3] The ancestral condition for canids is to have five toes on their forelimbs, but by the Early Pleistocene this lineage had reduced this to four, which is also a characteristic feature of the modern African wild dog (Lycaon pictus).

[3] The name was applied to Late Pliocene fossils of canids with hypercarnivorous dentition that were found in China at the sites Loc.

[6] Upper Valdarno is the name given to that part of the Arno valley situated in the provinces of Florence and Arezzo, Italy.

The Upper Valdarno Basin has provided the remains of three fossil canid species dated to the Late Villafranchian era of Europe 1.9-1.8 million years ago that arrived with a faunal turnover around that time (Early Pleistocene).

Both types of wolves could be found existing from England and Greece across Europe to the high latitudes of Siberia through to Transbaikalia, Tajikistan, Mongolia, and China.

[14] Fossil evidence to dated 1.8 million years ago from Dmanisi, Georgia in the southern Caucasus suggests that they were cooperative hunters which cared for their sick, injured and disabled pack members similar to the modern grey wolf.

[17] It preyed on antelope, deer, elephant calves, aurochs, baboons, wild horses and possibly humans.