Cretalamna borealis shark tooth?

[bthemoose]

I picked up the shark tooth below a while back, labeled as Cretalamna borealis. I'm not very familiar with the species--does this ID appear to be correct?

 

The label that came with the tooth says it was found near Stary Oskol, Belgograd Oblast, Russia, and that it's Upper Albian in age from the Kursk Osteolite member of the Seversk Sandstone formation. The tooth measures 38.6 mm along the slant. One of the root corners is missing and there's some hard matrix still cemented to the tooth near the root margin of the lingual side.

 

@ThePhysicist, I think this one might be a Dwardius woodwardi or Dwardius sp., but I'm not sure.

 

 

 

 

 

 

[fossilsonwheels]

Siversson wrote a great paper on Cretalamna which includes C. borealis. Google it and you should be able to find the paper available through  Research Gate. 

 Im no expert and am probably wrong but when looking at the paper , C. borealis might be the correct ID. 

[bthemoose]

4 hours ago, fossilsonwheels said:

Siversson wrote a great paper on Cretalamna which includes C. borealis. Google it and you should be able to find the paper available through  Research Gate. 

 Im no expert and am probably wrong but when looking at the paper , C. borealis might be the correct ID. 

Thanks! I’ve read the paper, but am unsure if the description of C. borealis is a fit for this tooth. Siversson describes that species from the Campanian, which is younger than this tooth is purported to be. The cusplets of C. borealis also appear to be more rounded. That said, I don’t have much or any experience with this species as I’ve either only seen its tooth in person once (this tooth) or not at all. The same goes for Dwardius, which is my thought for an alternative ID.

[fossilsonwheels]

As I stated, I’m no expert. I personally haven’t seen a Dwardius with cusplets that point outward quite like that but I’ll be the first to say my knowledge of all Cardobiodontids is very limited. I honestly can’t even say I know the proper species to assign to a Cretalamna from the Albian lol 

 

I believe Dr. Siversson is a member here though not sure if still active. Try tagging him. 

Edited July 14, 2022 by fossilsonwheels

[bthemoose]

@siteseer @ThePhysicist @Anomotodon @Al Dente @MikaelS, any thoughts on this one? Thanks in advance!

[hemipristis]

Nifty tooth, whatever the ID

[ThePhysicist]

I don't believe this is Cretalamna, it has a thicker dental band and the base of the crown on the lingual face has a very smooth, large "U" shape rather than a "V." I would say it's Cardabiodontid, and seems to match several traits of Dwardius. Again, I defer to Dr. Siversson's judgement if he gets to see this tooth.

 

Not sure where you keep finding these wonderful teeth, but keep 'em coming!

 

D. woodwardi:

^http://www.chalk.discoveringfossils.co.uk/5 Otodontids.htm

 

 

[bthemoose]

Thanks for taking a look @ThePhysicist and for your thoughts on the ID! I think this is the last “hidden” Cardabiodontid in my collection.

[MikaelS]

On 7/14/2022 at 4:47 AM, bthemoose said:

I picked up the shark tooth below a while back, labeled as Cretalamna borealis. I'm not very familiar with the species--does this ID appear to be correct?

 

The label that came with the tooth says it was found near Stary Oskol, Belgograd Oblast, Russia, and that it's Upper Albian in age from the Kursk Osteolite member of the Seversk Sandstone formation. The tooth measures 38.6 mm along the slant. One of the root corners is missing and there's some hard matrix still cemented to the tooth near the root margin of the lingual side.

 

@ThePhysicist, I think this one might be a Dwardius woodwardi or Dwardius sp., but I'm not sure.

 

 

 

 

 

 

It's a Dwardius. Zhelezko named D. siversoni from this deposit (see discussion in Siversson & Machalski 2017).

[MikaelS]

On 7/24/2022 at 1:00 AM, ThePhysicist said:

I don't believe this is Cretalamna, it has a thicker dental band and the base of the crown on the lingual face has a very smooth, large "U" shape rather than a "V." I would say it's Cardabiodontid, and seems to match several traits of Dwardius. Again, I defer to Dr. Siversson's judgement if he gets to see this tooth.

 

Not sure where you keep finding these wonderful teeth, but keep 'em coming!

 

D. woodwardi:

^http://www.chalk.discoveringfossils.co.uk/5 Otodontids.htm

 

 

Of those two teeth from the English Chalk, the one to the left is a Cardabiodon ricki (very similar to some of the lower lateroposteriors of the holotype) and the one to the right is Dwardius woodwardi.

[bthemoose]

2 minutes ago, MikaelS said:

It's a Dwardius. Zhelezko named D. siversoni from this deposit (see discussion in Siversson & Machalski 2017).

Thank you! I’ll look for that paper.

[MikaelS]

On 7/14/2022 at 4:47 AM, bthemoose said:

I picked up the shark tooth below a while back, labeled as Cretalamna borealis. I'm not very familiar with the species--does this ID appear to be correct?

 

The label that came with the tooth says it was found near Stary Oskol, Belgograd Oblast, Russia, and that it's Upper Albian in age from the Kursk Osteolite member of the Seversk Sandstone formation. The tooth measures 38.6 mm along the slant. One of the root corners is missing and there's some hard matrix still cemented to the tooth near the root margin of the lingual side.

 

@ThePhysicist, I think this one might be a Dwardius woodwardi or Dwardius sp., but I'm not sure.

 

 

 

 

 

 

 

 

 

 

 

 

Dwardius is very common in the upper Albian of Stary Oskol (these Albian strata overlie iron ore deposits which is what they mine).

[MikaelS]

2 minutes ago, bthemoose said:

Thank you! I’ll look for that paper.

Send me a request to my museum email and I will send you a pdf.