Wikipedia's Cretolamna

[Alex_lovegrove]

Hi everyone, I am seeking more information about the spectacular Cretolamna fossil featured in the respective wikipedia article.  Aside from being a great fossil it has some interesting features, such as a large second dorsal fin.  However, there doesn't seem to be anything else online about this specimen.  Does anyone know anything about this - is it in a private collection?  Can it actually be referred to Cretolamna?  

 

 

[piranha]

1 hour ago, Alex_lovegrove said:

...Does anyone know anything about this - is it in a private collection?...

 

 

There appears to be some glass reflection in the image that might indicate an institutional holding.

[Macrophyseter]

An educated guess can be made that the fossil is probably from the Cretaceous lagersattes from Lebanon, maybe Hgula, based on the color of the rock and the association with other animals best known there IMO.

 

There should always be the possibility of misidentification as Wikimedia Commons (the associated website Wikipedia images are uploaded from) allows any and every non-copyright image to be uploaded by anyone.

 

IMO, I believe that the fossil may be a misidentification, and the shark might instead be either one of two sharks- a sand tiger of or similar to the genus Otodontispis, or a goblin shark like Scapanorhynchus (both of which are known from Lebanon), although this is obviously just a guess. Outside similarities between the general body forms (especially the large second dorsal of similar sizes with the first) between the sharks, there's one possible evidence to back this up.

As circled in red, there something at the jaw that appears to be a detached tooth. If we assume that it is a tooth, it lacks visible lateral cusplets and has a very slender root, which is very unlike Cretalamna teeth as far as I know. IMO, it resembles more of an odontaspidid or mitsukurinid tooth. 

 

Here's a comparison with another complete Lebanese cretaceous shark fossil identified as Odontaspis arculeatus?.

 

 

But I am by no means an expert and this is just my guess. It's always possible that I am wrong and the Wikipedia fossil is indeed Cretalamna. 

[Macrophyseter]

1 hour ago, piranha said:

There appears to be some glass reflection in the image that might indicate an institutional holding.

But private collections can also put their specimens behind glass.

[Miocene_Mason]

I can’t say without a good view of the teeth. However, there is a (definitely legitimate) described Cretalamna skeleton from the Niobrara chalk, here’s  the paper on it. The paper says:

 

“Although the specimen is a partial skeletal remain, it represents the most well-preserved specimen of the species thus far known providing new anatomical information.”

 

Considering it looks less complete than the wiki skeleton, and considering this paper was done in 2007 by one of the most prominent paleoshark experts (Kenshu Shimada), that throws some doubt on the validity of the Wikipedia specimen. Now, the wiki picture was uploaded in 2012, so it is possible that it was found afterwards, but I couldn’t find any references to a paper on it. That would mean that if it really is a Cretalamna, I would bet it was in a private collection. Would also not doubt some “enhancing” had been done with paint, though I cannot be sure.

[piranha]

4 hours ago, piranha said:

There appears to be some glass reflection in the image that might indicate an institutional holding.

 

2 hours ago, Macrophyseter said:

But private collections can also put their specimens behind glass.

 

 

That's why I said "might"!

[Alex_lovegrove]

Thanks everyone for the replies!  Your comments have helped things get a bit clearer in my mind.

 

9 hours ago, WhodamanHD said:

Considering it looks less complete than the wiki skeleton, and considering this paper was done in 2007 by one of the most prominent paleoshark experts (Kenshu Shimada), that throws some doubt on the validity of the Wikipedia specimen. 

Agree with you here - Shimada's paper was the only one I could find on the body form as well. It's good to have that backed up!

 

10 hours ago, Macrophyseter said:

IMO, I believe that the fossil may be a misidentification, and the shark might instead be either one of two sharks- a sand tiger of or similar to the genus Otodontispis, or a goblin shark like Scapanorhynchus (both of which are known from Lebanon), although this is obviously just a guess.

Thanks for your thoughts and the images of Odontaspis arculeatus, that was really interesting...The wiki pic seemed a bit suspect before with no information, but now I'm very doubtful of the attribution.   

 

 

[Macrophyseter]

16 hours ago, WhodamanHD said:

I can’t say without a good view of the teeth. However, there is a (definitely legitimate) described Cretalamna skeleton from the Niobrara chalk, here’s  the paper on it. The paper says:

 

“Although the specimen is a partial skeletal remain, it represents the most well-preserved specimen of the species thus far known providing new anatomical information.”

 

Considering it looks less complete than the wiki skeleton, and considering this paper was done in 2007 by one of the most prominent paleoshark experts (Kenshu Shimada), that throws some doubt on the validity of the Wikipedia specimen. Now, the wiki picture was uploaded in 2012, so it is possible that it was found afterwards, but I couldn’t find any references to a paper on it. That would mean that if it really is a Cretalamna, I would bet it was in a private collection. Would also not doubt some “enhancing” had been done with paint, though I cannot be sure.

Also, Siverson et al. (2015) revisited the same Cretalamna skeleton in Shimada (2007) and I think still implies it is the most complete known to them. (Fun fact, he erected a new species for that fossil, Cretalamna hattini.) However, not all existing fossils get to be mentioned in scientific literature, especially if they are held privately.

 

The Sauriermuseum Aathal (The private museum that found and houses the other Big Al skeleton) holds this phenomenal Cretoxyrhina skeleton from Lebanon, which arguably has the preservation rivaling that of other extreme skeletons such as FHSM VP-2187 and has a tail fossil possibly more complete than CMN 40906.

 

Besides one grad student on Twitter, I don't know of any other mention of this fossil elsewhere in the scientific community, possibly because it's difficult to access as its part of the SMA private collection.