| Polyonax Temporal range: Late Cretaceous, | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Dinosauria |
| Clade: | † Ornithischia |
| Clade: | † Ceratopsia |
| Family: | † Ceratopsidae |
| Genus: | † Polyonax Cope, 1874 |
| Species: | †P. mortuarius |
| Binomial name | |
| †Polyonax mortuarius Cope, 1874 | |
| Synonyms | |
| |
Polyonax (meaning "master over many") is a genus of ceratopsid dinosaur from the Late Cretaceous (late Maastrichtian) Denver Formation [ citation needed ] of Colorado, United States. Founded upon poor remains, it is today regarded as a dubious name.
During an 1873 trip through the western US, paleontologist and naturalist Edward Drinker Cope collected some fragmentary dinosaurian material which he soon named as a new genus. [1] Catalogued today as AMNH FR 3950, [2] the type material included three dorsal vertebrae, limb bone material, and what are now known to be horn cores, from a subadult individual. [3] Although it was briefly mixed up with hadrosaurs, and even considered to be a possible synonym of Trachodon , [4] it was recognized as a horned dinosaur in time for the first monograph on horned dinosaurs (1907), wherein it was regarded as based on indeterminate material. [5] Today, the name is used as little more than a historical curiosity, as it dates from a time before horned dinosaurs were known to exist. [6] The most recent review listed it as an indeterminate ceratopsid. [7]
It has sometimes been listed as a synonym of Agathaumas , [8] or Triceratops . [9]
As a ceratopsid, Polyonax would have been a large, quadrupedal herbivore, with brow and nasal horns and a neck frill. [7]