Polyonax

Taxobox
name = "Polyonax"
status = Fossil
fossil_range = Late Cretaceous
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Ornithischia
subordo = Cerapoda
infraordo = Ceratopsia
familia = Ceratopsidae
subfamilia = Ceratopsinae
genus = "Polyonax"
genus_authority = Cope, 1874
binomial = "Polyonax mortuarius"
binomial_authority = Cope, 1874

"Polyonax" (meaning "master over many") was a genus of ceratopsid dinosaur from the late Maastrichtian-age Upper Cretaceous Denver Formation of Colorado, USA. Founded upon poor remains, it is today regarded as a dubious name.

History

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.Cope, E.D. (1874). Report on the stratigraphy and Pliocene vertebrate paleontology of northern Colorado. "Bulletin of the U.S. Geological and Geographical Survey of the Territories". 9:9-28.] Catalogued today as AMNH 3950, the type material included three dorsal vertebrae, limb bone material, and what are now known to be horn cores, from a subadult individual.cite book|title=Dinosaurs: The Encyclopedia|year=1997|chapter=Polyonax|author=Glut, D.F.|pages=723-724.|publisher=McFarland & Company|id=ISBN 0-89950-917-7] Although it was briefly mixed up with hadrosaurs, and even considered to be a possible synonym of "Trachodon",Hatcher, J.B. (1902). The genus and species of the Trachodontidae (Hadrosauridae, Claosauridae) Marsh. "Annals of the Carnegie Museum" 14(1):377-386.] 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.Hatcher, J.B., Marsh, O.C., and Lull, R.S. (1907). "The Ceratopsia". Government Printing Office:Washington, D.C., 300 pp. ISBN 0405127138] 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.cite book|title=The Horned Dinosaurs|year=1996|author=Dodson, P.|publisher=Princeton University Press:Princeton, New Jersey|id=ISBN 0-691-02882-6] The most recent review listed it as an indeterminate ceratopsid.Dodson, P., Forster, C.A., and Sampson, S.D. (2004). "Ceratopsidae". In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). "The Dinosauria" (second edition). University of California Press:Berkeley, 494-513. ISBN 0-520-24209-2.]

It has sometimes been listed as a synonym of "Agathaumas",Romer, A.S. (1956). "Osteology of the Reptiles". University of Chicago Press:Chicago, 1-772. ISBN 0-89464985-X.] or "Triceratops",Lambert, D., and the Diagram Group. (1990). "The Dinosaur Data Book". Facts on File:Oxford, England, 320 p.] but the type remains are too poor for any sort of definite synonymization.

Paleobiology

As a ceratopsid, "Polyonax" would have been a large, quadrupedal herbivore, with horns and a neck frill.

References