(News) Is Saurophaganax a chimera (Danison et al., 2024a)!?

Saurophaganax in Planet Dinosaur (2011):

I already talked about one abstract from SVP (2024), but there's another one that I need to discuss regarding another theropod I've talked about before.

We finally got some more research on the enigmatic theropod, Saurophaganax, brought to us by Danison et al., (2024). However, the authors of this abstract have made some pretty surprising claims that could change our view on the theropod completely... For example, the scientists claim that Saurophaganax wasn't even a theropod!

Danison et al., (2024) examined the Saurophaganax material. They started off with a fourth metatarsal, which showed signs of fast growth and what appears to be an External fundamental System (EFS). This doesn't seem to match the growth trajectory of Allosaurus, thus the authors separate Saurophaganax from Allosaurus. That is, if "the appositional rate of the metatarsal is representative of the whole animal." However, it's the last conclusion that floored me. The authors stated that the Saurophaganax vertebral elements (atlas and dorsal vertebrae, and the caudal chevrons) belonged to sauropods and not theropods! In fact, they might belong to an already established sauropod taxon. The holotype of Saurophaganax is the mid-dorsal neural arch (dorsal vertebra) (Chure, 1995, pp. 104 and 106). Based on Danison et al., (2024), this would make Saurophaganax a sauropod or a synonym of another sauropod! The name "Saurophaganax" might not even exist anymore... The skull and limb/long bone elements, said to have belonged to Saurophaganax, do resemble theropoda though. In particular, they are "largely consistent with Allosaurus." (SVP, 2024, pp. 164-165).

Danison et al., (2024 [SVP, 2024]):
P. 164:

P. 165:

Honestly, I don't know what to think. I was certain that the Saurophaganax material belonged to a  carcharodontosaurid. However, some of the bones did resemble Allosaurus, like the giant humerus OMNH 01935. Chure (1995) said that the bone was "robust," yet "closely resembles that of Allosaurus," (p. 103). Smith (1998) said that the humerus matched the Allosaurus growth chart and "non-size-related variation," despite being large (pp. 131, 134, 138-139). In fact, Smith said that the Saurophaganax material "lies on the same growth trajectory for Allosaurus in almost every case," (p. 140). I've also noted before that OMNH 01935 is morphologically indistinct from other humeri of Allosaurus. Saurophaganax was more of a chimera than people thought. Heck, I originally asserted that Saurophaganax was a chimera (half carcharodontosaurid and half Allosaurus) until I discovered that other carcharodontosaurid taxa had similar bones to it, excluding OMNH 01935. The giant humerus still confused me, but I still thought that it belonged to Allosaurus. I still think that. In fact, aside from (possibly) the fourth metatarsal and the vertebrae, other postcrania bones resemble Allosaurus', according to Danison et al., (2024). 

I decided to see if it was possible for the "Saurophaganax" atlas to resemble a sauropod's atlas, or not. I saw Apatosaurus louisae's atlas, and... Yeah, they look really similar:

Apatosaurus louisae's atlas and axis ("at" is atlas) (Gilmore, 1936, p. 192):

"Saurophaganax's" atlas (OMNH 01135) (Chure, 1995, p. 104):

"Saurophaganax" was a chimera after all... I truly believe that some Allosaurus bones got jumbled up in the skeletal material. Now, it seems that some Allosaurus AND probably some sauropod bones got mixed in there as well. I wonder if there's any actual "Saurophaganax" material left to keep the taxonomic name alive?

I'm not going to make any final conclusions until the authors finish their paper. I want to give them a chance, and go about this with an open mind. If this is the end of "Saurophaganax,' then so be it. It was a lot of fun to research the animal. 

Links:
Danison et al., (2024) (SVP, 2024, pp. 164-165):
https://vertpaleo.org/wp-content/uploads/2024/10/2024_SVP_Program_Final3.pdf
Gilmore (1936) (P. 192):
https://www.biodiversitylibrary.org/page/53145444#page/254/mode/1up
Chure (1995):
https://www.researchgate.net/publication/230892243_A_reassessment_of_the_gigantic_theropod_Saurophagus_maximus_from_the_Morrison_Formation_Upper_Jurassic_of_Oklahoma_USA
Smith (1998):
https://www.researchgate.net/publication/272151969_A_morphometric_analysis_of_Allosaurus