Article · Wikipedia archive · Last revised Jul 17, 2026

Palaeosyops

Palaeosyops is a genus of small brontothere which lived during the early to middle Eocene.

Last revised
Jul 17, 2026
Read time
≈ 1 min
Length
275 w
Citations
3
Source
Wikipedia ↗
Palaeosyops
Temporal range: Early–Middle Eocene (Bridgerian),
P. robustus skeleton
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Infraclass: Placentalia
Order: Perissodactyla
Family: †Brontotheriidae
Genus: †Palaeosyops
Species
  • P. dayi
  • P. paludosus Leidy, 1870 (type)
  • P. robustus (Marsh, 1872)

Palaeosyops (Greek: "old" (paleos), "boar" (kapros), "face" (ops)2) is a genus of small brontothere which lived during the early to middle Eocene.3

Biology and size

P. robustus skull collected from Bridger Basin, Wyoming with model by Erwin S. Christman, AMNH. source ↗

It was about the size of small cattle, with an estimated weight of 408.5 kilograms (901 lb).4

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.

Restoration by Charles R. Knight source ↗
References

References

  1. Hodnett, John-Paul M.; Welsh, Edward T.; Santucci, Vincent L.; Tweet, Justin S. (2022). "A Middle Eocene brontothere (Mammalia; Perissodactyla; Brontotheriidae) from Yellowstone National Park, Wyoming". FOSSIL RECORD 8. New Mexico Museum of Natural History and Science. p. 211.
  2. "Glossary. American Museum of Natural History". Archived from the original on 20 November 2021.
  3. "Fossilworks: Palaeosyops".
  4. Sanisidro, Oscar; Mihlbachler, Matthew C.; Cantalapiedra, Juan L. (2023). "A macroevolutionary pathway to megaherbivory". Science. 380 (6645): 616–618. doi:10.1126/science.ade1833. Supplemental Material (Data S1, Sheet 6)
External links