Hell Creek Bone ID Needed

[Kohler Palaeontology]

Hello everyone,

 

I acquired this bone a good few years ago now and I am still trying to figure out what it is. It was found in the Hell Creek Formation of Montana; I don't know what county it was found in. I believe it could be a Triceratops epijugal or a Pachycephalosaurus head node. It is not a worn chunkosaur, I can tell this is the shape of the bone, although it is a bit worn. Those large grooves on photo 2 and 4 and 7, could they be bite marks as that side of the bone has a texture of which reminds me of healed bone, what do you all think? The number is just my collection number for it, it's not my 18th fossil, but the 18th one I numbered. 

 

 

Any help is appreciated

 

Kind Regards,

Kohler Palaeontology

[hadrosauridae]

This is very worn.  I dont see any remains of cortical bone left.  There looks to be some faint traces of vascular lines usually associated with ceratopsians, but I dont know if this can be IDd to an element or species.   If you thinks its a specific element, best bet would be to start reading papers on those species and study the drawings and descriptions for a match.

[Kohler Palaeontology]

Thanks for the reply! I have seen epijugals take many different shapes before, some of which tend to match relatively close to this.

 

Do you think there could be bite marks though? The bone in texture changes to a finer, spongier texture right where there are large grooves. Or is it something else? 

[hadrosauridae]

1 hour ago, Kohler Palaeontology said:

Thanks for the reply! I have seen epijugals take many different shapes before, some of which tend to match relatively close to this.

 

Do you think there could be bite marks though? The bone in texture changes to a finer, spongier texture right where there are large grooves. Or is it something else? 

 

Predation marks can be difficult to positively ID even in very well preserved bones.  Those lines do appear very straight and *could* be from a strong bite, but its just guessing.  With the amount of wear, it could also have been caused during taphonomy.

[jpc]

I agree with hadr's thoughts.  Epijugals have a concave surface where they attach to the jugal.  I am not seeing this on this bone.  I thing this is a rather waterworn chunkosaur.  I have seen a lot of tumbled bone this big that do not show cortical bone.