Charcharocles Vs Otodus Auriculatus

[Josh_irving]

Hello everyone,

 

Recently just purchased this Auriculatus tooth from the Qsar-el-sagha Formation in Egypt. Whilst making a label for it I have learnt that there is a lot of debate on what genus it belongs to. The two options being Charcharocles and Otodus.

 

It is my understanding that American Paleontologists believe it is from the Charcharocles genus as it has serrations (Otodus not having serrations). In juxtaposition eastern European Paleontologists believe that serrations vs non-serrations is not enough evidence for it to be consider a species of Charcharocles and believe it is a species of Otodus.

 

Case and Cappetta (1990), the review of the Eocene fauna in the Fayum Depression of Egypt (where this tooth comes from) calls it a Charcharocles however several people have told me it does indeed belong to the genus Otodus.

 

Was wondering if anyone here has followed this issue more closely and could inform me if there was now an “accepted” genus.

 

Thanks in advance,

Josh

 

[Kikokuryu]

There's arguments for both, but as it is currently understood, Otodus is currently the favorite, with Carcharocles being a junior synonym of Otodus as the Carcharocles lineage is a assumed to be a direct descendent of Otodus obliquus. This also makes transitional Otodus obliquus easier to ID and label.

[Rock Hound]

That is a nice, choice specimen.  Thanks for sharing.

 

I have many Otodus Obliquus teeth, a couple of damaged Angustidens, and a few Megs. The other variants, always catch my eye.

[Josh_irving]

On 9/21/2023 at 4:48 PM, Kikokuryu said:

There's arguments for both, but as it is currently understood, Otodus is currently the favorite, with Carcharocles being a junior synonym of Otodus as the Carcharocles lineage is a assumed to be a direct descendent of Otodus obliquus. This also makes transitional Otodus obliquus easier to ID and label.

 

Thank you for the information. I agree that it looks more like an Otodus tooth as apart from the serations it looks like many other Otodus teeth including Otodus obliqus.

 

Do you know what the species are from the jump from Otodus to Carchorocles

[Josh_irving]

On 9/22/2023 at 12:45 PM, Rock Hound said:

That is a nice, choice specimen.  Thanks for sharing.

 

I have many Otodus Obliquus teeth, a couple of damaged Angustidens, and a few Megs. The other variants, always catch my eye.

 

Thank you very much. I also like how this tooth comes from an unusual locality of Egypt.

 

 

I still need to get a couple of obliqus teeth for my collection. Been looking for a some really good ones to add to my collection.

[Kikokuryu]

49 minutes ago, Josh_irving said:

Do you know what the species are from the jump from Otodus to Carchorocles

Oh, I meant that all Carcharocles are Otodus. So Otodus obliquus all the way to Otodus megalodon.

 

That said, I think it was Otodus akusaticus that would be the transition between Otodus obliquus and Otodus auriculatus.

 

So the cronospecies would go like this.

 

O. obliquus -> O. aksuaticus -> O. auriculatus -> O. sokolovi -> O. angustidens -> O. chubutensis -> O. megalodon

 

You can make really cool Otodus evolution displays, especially if you get them all around the same size and tooth position.

Edited September 25, 2023 by Kikokuryu

[Notidanodon]

All the important stuff has been said (all Carcharocles species are now classed within Otodus (to some people’s displeasure )) but I would like to say what a fantastic tooth  

one thing to add is there are many transitional species that are poorly defined. Otodus mughodzharicus is between Obiquus and askuatis and is only serrated at the base but then there are others like O.poseidoni that I honestly couldn’t tell you the features of.
it’s all a sliding scale  of evolution so I sometimes wonder why we bother making everything fit into rigid categories but there we go  it looks neater in a book!

 

quick question do you know the age of that formation as the serrations present a little weakly for auriculatus?

[Josh_irving]

1 hour ago, Notidanodon said:

All the important stuff has been said (all Carcharocles species are now classed within Otodus (to some people’s displeasure )) but I would like to say what a fantastic tooth  

one thing to add is there are many transitional species that are poorly defined. Otodus mughodzharicus is between Obiquus and askuatis and is only serrated at the base but then there are others like O.poseidoni that I honestly couldn’t tell you the features of.
it’s all a sliding scale  of evolution so I sometimes wonder why we bother making everything fit into rigid categories but there we go  it looks neater in a book!

 

quick question do you know the age of that formation as the serrations present a little weakly for auriculatus?

 

Thanks for the info. I agree, evolutionary differences are a gradient (shades of gray) and don't always fit in definitive boundaries. 

 

This tooth is Late Eocene in age, more specifically middle priabonian. 

[Notidanodon]

25 minutes ago, Josh_irving said:

 

Thanks for the info. I agree, evolutionary differences are a gradient (shades of gray) and don't always fit in definitive boundaries. 

 

This tooth is Late Eocene in age, more specifically middle priabonian. 

In that case I would call it Otodus soklovi  

[Josh_irving]

27 minutes ago, Notidanodon said:

In that case I would call it Otodus soklovi  

 

Ok interesting, was this previously know to be "the same" as O. auriculatus and that's why it was labeled wrong?

 

 

[Notidanodon]

1 minute ago, Josh_irving said:

 

Ok interesting, was this previously know to be "the same" as O. auriculatus and that's why it was labeled wrong?

 

 

No it’s just a little later on than auriculatus but a lot of people would just call them the same thing as it is just a chrono species. So it’s not necessarily wrong and I could be mistaken either way  

[Al Dente]

8 hours ago, Kikokuryu said:

Oh, I meant that all Carcharocles are Otodus. So Otodus obliquus all the way to Otodus megalodon.

 

That said, I think it was Otodus akusaticus that would be the transition between Otodus obliquus and Otodus auriculatus.

 

So the cronospecies would go like this.

 

O. obliquus -> O. aksuaticus -> O. auriculatus -> O. sokolovi -> O. angustidens -> O. chubutensis -> O. megalodon

 

You can make really cool Otodus evolution displays, especially if you get them all around the same size and tooth position.

Here’s an interesting article by Bob Purdy on the confusion between auriculatus and angustidens (starts on page 8)- https://www.calvertmarinemuseum.com/DocumentCenter/View/666/Volume-10-Number-3-Fall-1994?bidId=

 

I think Agassiz gave different names to the same species. He named the narrow lower anterior teeth “angustidens” and the broad lateral teeth “auriculatus “.  
 

 

Edited September 25, 2023 by Al Dente

[Notidanodon]

@Al Dente so are they not chrono species? Sorry that article confused me a little  

[Al Dente]

2 hours ago, Notidanodon said:

@Al Dente so are they not chrono species? Sorry that article confused me a little  

They definately change through time. I think the point of the article is that the names auriculatus and angustidens have been confused over the years and some might argue that they should no longer be used.