Tyrannosaurus Metacarpal

[billyatom]

I've a large metacarpal that i'm sure if from a Tyrannosaurus, however, i'm not certain of the species.  i found it in the Judith formation in the Montana Milk River Badlands just a mile or so south of Alberta.  it measures 6 3/4" long, 3" tall and 3 1/4" across, but i don't think that information is important in the ID.  Any help in ID even of where in the foot it's from would be appreciated.

[bcfossilcollector]

I think all of the information you have provided is very important!  Location of a find along with a detailed description of a fossil's characteristics are essential in the identification of any specimen. Unfortunately I cant help with the id of your particular find but I am certain that some of the forum experts will be by shortly to provide an analysis. 

[Susan from PA]

This is interesting indeed.  I cannot comment on whether or not this is Tyrannosaurid, but at 7 inches in length and over 3 inches in diameter at the proximal end, I'm leaning toward it being a large theropod toe phalanx.   Maybe @Troodon can help us further.   

[LordTrilobite]

I'm not sure how hollow the metacarpals of Tyrannosaurids are. But I find it interesting that seems doesn't seem to be much of a cavity here.

[Troodon]

Can you post a picture of looking straight down at the top of the bone and a lateral view without any obtuse angles.  Also a shot straight in of both broken pieces.  Like Susan said looks like a phalanx of toe not a metacarpal.  It's an interesting bone expected to be hollow. 

[JohnJ]

@Opisthotriton @jpc

[jpc]

troodon has said all I wanted to say.  I don't have my field guide to T rex bones handy, but yes, a photo from the top would be helpful. 

 

In any case, tyrannosaurs form the Judith River are Daspletosaurus, Gorgosaurus and Albertaosaurus.  So it is one of these three, but likely not identifiable to genus.   

Why does Albertosaurus have an O in the middle and not an A?  Isn't it named after the Canadian province?  Is due to it a rule of Latin?  

[Ridgehiker]

Nice specimen

 

Re your locale.

This will be be Dinosaur Park Formation.  

 

There isn't much research on the Montana side but more published info on vertebrates across the 'imaginary line' in Alberta.  Look up 'Kennedy Coulee'.  Its a really remote area that has had a few research projects in the last couple decades.  Ive only accessed it once and was blown away by the potential.  I could hike a lifetime and barely scratch the surface.  For whatever reason, its rich not only in dino remains but also mammal teeth.

If you hike along the Milk River be sure to check out any thin greyish layers...especially up high.  These can contain shark teeth.

[Ridgehiker]

2 hours ago, jpc said:

Why does Albertosaurus have an O in the middle and not an A?  Isn't it named after the Canadian province?  Is due to it a rule of Latin?  

 

I'll be a bit pedantic ( 4 years of Latin in school).

 

'Saurus' is a second declension noun. The 'us' ending is a common nominative singular ending. 98% of the time masculine gender.  Its Alberto and not Alberta as it is modifying this noun.  

 

However, one needs to know what the genus or species is named for.  Alberta, Albertan, 'of' Alberta (genetive case) 'in'Alberta (ablative case), etc.  Thus Alberta could be Alberta, Albertae, 

Albertensis, Albertenses.

 

Sometimes you will see a correction in a journal that officially corrects a past genus/species name due to an error in the Latin.  However, most of the time nobody really cares and the name is used in its original 'bad Latin' form.

 

 

 

 

[Kane]

* checks his ratty old copy of Wheelock's * 

 

"By golly, @Canadawest is right! But can he translate "internet" without relying on the calque-form of tela totius terrae?"

 

And, just in good fun, the root of "pedantic" is, by some linguistic route, tied to pedagogue. Now, some of us may think we're being fancy in claiming that we adhere to principles of pedagogy, but in its most classic definition, pedagogue effectively means "he who accompanies the child to school by foot" - or, in more modern parlance, a truant officer.  

[jpc]

I knew someone here would know more Latin than me. 

[Ridgehiker]

Latin was my favourite subject in school.

 

The first week you never learn. 'My name is.....Where can I buy a loaf of bread?'

 

instead its  'Caesar's army conquered Britain and ordered his army to set up camp and secure the perimeter with ramparts.'

 

The first week I learned that place names ending  with chester, ceister, caster, etc were all derived from the word meaning a Roman military camp. After that  I was hooked.  My girlfriend is from Man'chester' first founded as a Roman fort.

 

Thread hijacked.  Its a phalange from  a Tyrannosaur but not possible to ID genus.

[abyssunder]

For comparative reason, here is an excerpt from Christopher A. Brochu. 2003. Osteology of Tyrannosaurus rex: Insights from a Nearly Complete Skeleton and High-Resolution Computed Tomographic Analysis of the Skull. Society of Vertebrate Paleontology Memoir 7. Journal of Vertebrate Paleontology 22(sup4):1-138 .

 

 

 

[Troodon]

I'm currently not on the same page as everyone else until I see additional pictures.  

I'm not sure this is a tyrannosaurid or even a theropod phalanx.  I say this for the following reasons, please correct me if I'm wrong:

 

The biggest factor in my mind is that Theropod toe bones are hollow unlike the one in question.  I don't think tyrannosaurid are different, are they?

Here is a photo of a broken phalanx from an Anzu one both ends.  The back end still has matrix in it.

 

The following features are found in tyrannosaurids like Daspletosaurus or Gorgosaurus and I'm having a hard time seeing them in the specimen in question why additional photos are needed.

 

Here are just three

-Dimples are present on the dorsal surface just behind the knuckle. 

-The proximal end flares out on phalanx 1

-The ventral side has a big arch in the center.

 

I've attached foot photos of two tyrannosaurid found in the Judith River so you can compare the bones..  Sorry their the best ones I have.

 

Daspletosaurus 

 

Gorgosaurus 

 

[jpc]

troodon, while I agree with the hollowness argument, what else out there has such big round divots on the distal ends?  (I know these things have a name, but it escapes me).

[Troodon]

4 hours ago, jpc said:

troodon, while I agree with the hollowness argument, what else out there has such big round divots on the distal ends?  (I know these things have a name, but it escapes me).

Ligament pits?   Why I said from my first post it's an interesting bone.