New Analysis Means that Saurophaganax maximus is Invalid

A not too long ago revealed scientific paper has challenged the validity of the theropod taxon Saurophaganax maximus.  The researchers conclude that S. maximus ought to be labeled as nomen dubium and a brand new taxon of Allosaurus is proposed – Allosaurus anax. In Latin, nomen dubium interprets as “uncertain identify”. Basically, which means the Saurophaganax genus is just not supported anymore.

Image credit score: Every part Dinosaur

Sorting Saurophaganax maximus

In 1995, palaeontologist Daniel Chure erected the genus Saurophaganax (S. maximus) to explain a particularly massive allosaurid dinosaur that had been excavated from the Kenton 1 Quarry in Cimarron County (Oklahoma) again within the Nineteen Thirties. Sadly, the dig web site was not that properly supervised and mapped when the bones had been initially excavated and eliminated. A number of dinosaur taxa had been current, and this may occasionally have led to confusion between what was outlined as theropod and what was considered sauropod fossil bone.

In his analysis, Chure proposed {that a} dorsal neural arch (OMNH 1123) be declared the holotype specimen for Saurophaganax maximus. This theropod was a lot bigger than Allosaurus fragilis and rivalled the large megalosauroid Torvosaurus tanneri for the title of the largest meat-eating dinosaur described to this point from the Morrison Formation. Certainly, the Kenton 1 Quarry fossils had been thought to symbolize one of many largest theropods recognized from the Jurassic of North America. Maybe these fossils could possibly be from one of many largest, Jurassic carnivorous dinosaurs that ever lived!

This new examine proposes that the holotype (OMNH 1123), doesn’t belong to a theropod.  The dorsal neural arch is harking back to that of a juvenile sauropod.  Different referred materials comparable to chevrons and the atlas can’t be assigned to the Theropoda with certainty.  Since fossil materials can’t be assigned to Saurophaganax, this taxon is taken into account not legitimate (nomen dubium).

Saurophaganax has a Chequered Historical past

This dinosaur was named as Saurophagus maximus in 1941.  It was later revised to Saurophaganax maximus when it was identified that the genus identify was already used to explain an extant chook.  Quite a few distinctive traits had been recognized within the fossil materials which had led to the institution of a brand new dinosaur taxon.  For instance, the postorbital bone within the cranium missing a postorbital boss and the atlas not having any aspects for a proatlas. Nevertheless, the 2024 re-evaluation exhibits that among the components initially used to differentiate Saurophaganax from Allosaurus are extra parsimoniously referred to diplodocid sauropods present in the identical quarry somewhat than an allosaurid.

This newest evaluation eliminates most of the beforehand reported traits that distinguished the Kenton 1 Quarry allosaurid from Allosaurus.  The analysis staff doesn’t take into account a definite genus is warranted. Regardless of the similarity of the decisively theropod materials to recognized species of Allosaurus, some components characteristic refined traits and traits that recommend they symbolize a definite Allosaurus species. Due to this fact, the researchers conclude that S. maximus be labeled as a nomen dubium and a brand new taxon of Allosaurus is proposed – Allosaurus anax.

Image credit score: Every part Dinosaur

The image (above) exhibits one of many Rebor Saurophaganax replicas that had been launched in 2022.

To view the vary of Rebor figures and fashions in inventory: Rebor Figures and Fashions.

In abstract, palaeontologists traditionally thought-about this taxon to symbolize a species of Allosaurus or a really massive allosaurid. Nevertheless, a re-examination of the attributed specimens means that it’s a chimera of a number of dinosaur genera. Some specimens seemingly belong to a diplodocid sauropod, whereas others could possibly be reassigned to a brand new species of Allosaurus (A. anax).

The scientific paper: “Chimerism of specimens referred to Saurophaganax maximus reveals a brand new species of Allosaurus (Dinosauria, Theropoda)” by Andy D. Danison, Mathew J. Wedel, Daniel E. Barta, Holly N. Woodward, Holley M. Flora, Andrew H. Lee, and Eric Snively revealed in Vertebrate Anatomy Morphology and Palaeontology.

The Every part Dinosaur web site: Dinosaur Toys and Fashions.