Mosasaur partial skeleton in matrix

[Ged]

Saw this Mosasaur skeleton for sale and I've been thinking for a while something like it would be cool. Unfortunately the auction site it is listed on has a bad record of fake or manipulated fossils and Mosasaurs in particular. I'm even more worried due to it being from Morocco. I highlighted some of the photos where the bones don't appear to align right or seem to be composited. Does this look manipulated? are sections entirely fake? does the matrix look genuine?

 

Also it is listed as a Halisaurus arambourgi is that the correct identification?

Thank you for your thoughts.

 

 

[Praefectus]

The identification is correct - Halisaurus arambourgi Bardet & Pereda Suberbiola 2005

 

You can see the diagnostic jugal in the piece and compare it to the one in @jnoun11's Moroccan Mosasaur thread (H. arambourgi is the top one). Frontal and teeth are also a match for H. arambourgi. 

 

 

I am not sure I would recommend recommending the piece to your collection, though. As you pointed out, it has a lot of repairs to it. The internarial bar and right dentary look to have fragmented and been glued back together. Also, the back of the skull (squamosal, parietal, supratemorpal, postorbitalfrontal, etc.) looks to be heavily reconstructed. For comparison, this is what an original Halisaurus arambourgi skull looks like. 

 

 

 

 

 

 

 

Edited July 10, 2023 by Praefectus

[pachy-pleuro-whatnot-odon]

I fully agree with Trevor's identification and recommendation.

 

The thing with most of these fossils is that they're actually found flattened/crushed on their sides. Thus, for the fossil to be reconstructed in three dimensions, as is the case here, the bones are prepared out of the matrix separately, then recombined into the skull's supposed original shape. However, certain parts of these skulls - like the internarial bar and pterygoids (though not in larger species) - are so fragile that they don't preserve well, thus are often reconstructed using complete fabrications. And since we're talking about a reconstruction in any case, the preparator may have even used bones from different specimens to get a single nice-looking skull. It's also not uncommon, even in the best of these specimens, for certain bones to have preserved in a broken state, so that when the skull is reconstructed, if this is not corrected, the final result will look off. I've seen H. arambourgi skulls where the frontal was broken, giving the resulting specimen a foreshortened appearance.

 

For comparison, here's a well-prepared prepared specimen: