| Palaeosyops Temporal range:   | |
|---|---|
|   | |
| P. robustus skeleton | |
|  Scientific classification   | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Class: | Mammalia | 
| Order: | Perissodactyla | 
| Family: | † Brontotheriidae | 
| Genus: | † Palaeosyops | 
| Species | |
  | |
Palaeosyops (Greek: "old" (paleos), "boar" (kapros), "face" (ops) [1] ) is a genus of small brontothere which lived during the early to middle Eocene. [2]
 It was about the size of small cattle, with a weight of 600–800 kg depending on the species. [3]
These animals are commonly found in Wyoming fossil beds primarily as fossilized teeth. P. major was the largest species, reaching the size of a small cow. Its describer, Joseph Leidy, erroneously thought that Palaeosyops consumed both plants and animals after examining the fang-like canines. However, it is now known that all brontotheres were strict herbivores, and that many, if not most genera of hornless brontotheres had fang-like canines, possibly for both defense from predators, and intraspecific competition.