ID on an alleged fused ulna & radius of an Allosaurus

[Sauroniops]

I found something from our favorite auction site that looks very interesting, however I have my doubts if it is legitimate or allosaurus, and would like to hear someone else's input.

 

Seller describes the item as a fused humerus and radius, but I am guessing they mean ulna and radius, of an Allosaurus, found in the morrison formation.

 

Do anyone have information regarding whether these bones even fuse in theropods, or whether they even resemble the ulna/radius bones of Allosaurus?

 

Thanks

 

 

[Troodon]

Not sure what this belongs to or fusion Q but the red circled bone appears to be one of the ankle bones like astragalus so I question if its a forelimb assemblage.

 

 

This is an Allo radius/ulna

[Mark Kmiecik]

Possibly a couple of metatarsals? But from what?

[Troodon]

29 minutes ago, Mark Kmiecik said:

Possibly a couple of metatarsals? But from what?

 

I thought of that but that bottom portion of the astragalus bone is what articulates with the metatarsals 

[Mark Kmiecik]

4 minutes ago, Troodon said:

 

I thought of that but that bottom portion of the astragalus bone is what articulates with the metatarsals 

 

Flipper?

[Sauroniops]

Could it perhaps be part of the lower leg of a crocodylomorph?

Edited June 27, 2022 by Sauroniops

[Troodon]

Very possible since we are looking at a Tib/Fib and they are short and stocky

[Sauroniops]

1 minute ago, Troodon said:

Very possible since we are looking at a Tib/Fib and they are short and stocky

 

I don't recall too much crocodylomorph material having been described from the Morrison though. At least not anything but teeth and jaw-pieces. But the short stocky structure also had me thinking croc. Has more crocodylomorph material been found in similar formations to the Morrison around the world?

[Troodon]

From the Morrison

 

[jpc]

This looks very mammalian.  I can't think of any reptile that actually fuse the radius/ulna.  and these are certainly radius/ulna.   Feel ree to correct me on that.  And the articulation on the proximal end (the semicircular indentation) is very mammalian.  I googles, whale raius/ulnaand eventaully ofund that manatees have this exact set-up.  

 

I vote manatee.

 

Certainly NOT allosaurus.

[Sauroniops]

I think you're correct @jpc, the similarity to the manatee ulna/radius is huge.

 

Think we can conclude it is not from the Morrison formation whatsoever. 

Edited June 27, 2022 by Sauroniops

[Harry Pristis]

Here an homologous radio-ulna:

 

[jpc]

I knew harry would show up; this is much more his thuckton.  Thanks for that harry.  I think some of the photos I saw when I did a google search for 'manatee radius' were probably yours.