Cretaceous Sharks

[Sélacien34]

Hello, here some teeth from the French Albien, all Lamniforms i think, i think that i know the genus but i would need other opinions about the species, thank you.

Edited April 5, 2014 by Sélacien34

[Foshunter]

Really need something for size, 1-3 look like Cretodus, not sure on #4. They are nicely preserved, great teeth----Tom

Edited April 1, 2014 by Foshunter

[Sélacien34]

You're right, thanks for your answer and sorry for the size. I think that it could be :

1 = 10 mm Archaeolamna sp./aff haigi

2 = 14 mm Protolamna sp.

3 = 8 mm Protolamna borodini

4 = 11 mm Scapanorhynchus praeraphiodon

[Sélacien34]

Am i right ? no idea ?

[Foshunter]

The pictures are very small when they are clicked on, hard to make a good ID. #2 & 3 could be Protolamna sp. I am not familiar with European teeth you mentioned, if they are of small size, 18 mm or so then I believe those are correct. #1 need more detailed picture and size of specimen. #4, need better picture of the root and area above that, once again a measurement----Tom

[Sélacien34]

I will take better pictures for 3 of them because the third one is not mine, it was just to confirm my opinion or not.

I thought the third one could have been a Protolamna borodini tooth, but it's difficult to see where is the difference with Protolamna sp. . It would be necessary for me to know all positions about those 2 different species. The crown and root seems to be more extended on Protolamna sp. than P. borodini. This is not the case here, how did you decide ?

[Sélacien34]

I have taken better pictures of those teeth :

1: 14 mm

2: 10,05 mm

3: 9 mm

[Sélacien34]

Another one :

4: 12 mm

[Foshunter]

I don't know my European teeth having to reference Texas Cretaceous teeth, so here is what I think.

Rows 1-2 Protolamna sp.

Row 3 Don't know possible Carcharias sp., nice tooth

Row 4 Leptostyrax sp.

Very improved pictures, great work----Tom

Edited April 5, 2014 by Foshunter

[Sélacien34]

Thank you very much for your answer Tom, the first pictures have been taken by the seller. I agree with you for the first one, Protolamna sp. About the second tooth, cusplets and massive root make me think to Archaeolamna.

About the third tooth, it's very difficult to identify, particularly small specimens are very difficult to separate from those of Carcharias striatula. (I refer on what was found in the Albian French but i'm not sure)

Carcharias sriatula 1,2 - Scapanorhynchus praeraphiodon 4

Diagnosis by Charlie J. and Mitchell, S.F. (1999) Albian and Cenomanian
selachian assemblages from North East England.

Genus SCAPANORHYNCHUS Woodward, 1889
Scapanorhynchus praeraphiodon Sokolov, 1978 ? sensu Biddle, 1993
Text-Figure 6, C-F
Material. Two identifiable specimens, LIVCM 1998. 20. BT-BS; isolated cusps probably
assignable to this taxon are frequent.
Horizon and localities. Speeton: Hunstanton Formation, Weather Castle Member, beds
WC 2 and WC 3 (upper Upper Albian). Isolated cusps assignable to this species are
present throughout the Hunstanton Formation at South Ferriby and more rarely within the
Dulcey Dock and Weather Castle Members at Speeton.

Description. The main cusp is high and slender, with a narrow, but well developed, cutting
edge. The labial face is almost flat, the convexity of the lingual face being greater in the
anterior teeth than in the laterals. Ornament is restricted to a series of slight folds in the
lower third of the lingual face. These are more strongly developed and straighter in the
lateral teeth. A pair of small lateral cusplets is present on a poorly developed crown tongue.
The root branches are strongly divergent, and a strong lingual protuberance is present in the
anterior teeth. The nutritive groove is strongly developed.

The fourth tooth could be a Leptostyrax because of the large lateral cusplets.

But i think that i would need more opinions about some of those teeth.

Edited April 7, 2014 by Sélacien34

[Sélacien34]

Hello Tom, i think that you are right, it's look like a Protolamna, shape and size are ok. This research is very useful to me. I think that it could be a rear tooth because of the short and asymmetric lobes of the root, where would you place it in the jaw?

What do you think about those 2 other teeth ? I will take better pictures from different views.

Edited April 7, 2014 by Sélacien34

[siteseer]

Hi Selacien34,

I am on a business trip so I do not have access to my references at home. However, if you can take a photo of the opposite sides, and a profile photo, I will give you my opinion. Also what are the sizes? At the moment I think the first tooth is Protolamna and the second is Archaeolamna.

Did you find these teeth? Where were they collected? They are interesting. I have only a few Albian teeth from Texas and a few from France.

Jess

Hello Tom, i think that you are right, it's look like a Protolamna, shape and size are ok. This research is very useful to me. I think that it could be a rear tooth because of the short and asymmetric lobes of the root, where would you place it in the jaw?

Protolamna aff. sokolovi-.PNG

What do you think about those 2 other teeth ? I will take better pictures from different views.

S 14 mm-.jpg14 mm.JPG

[Sélacien34]

Hello Jess, i didn't find those teeth because i don't live in this county, they all came from the Cretaceous/Albian of Courcelles (county : Aube/France). You can see here what species can be found at this place : http://users.skynet.be/somniosus/Albian_systematic.htm

What do you think about the first teeth presented, do you agree with the identifications that were made?

1,2 : Protolamna sp.

3 : Scapanorynchus praeraphiodon

4 : Leptostyrax

About the last 2 teeth, each measures 14 mm, i will take good pictures of them very soon, with all necessary angles of views.

Thank you very much for your help

Edited April 8, 2014 by Sélacien34

[Sélacien34]

Sorry for the delay, here the pictures :

The second looks like Archeolamna, but i'm not sure about them.

Edited April 10, 2014 by Sélacien34

[Sélacien34]

More teeth from the same place :

Tooth : 2,6 cm

Cretoxyrhina mantelli Anterior Sup. file 1?

Tooth : 2 cm

Protolamna sp. Ant. Inf. file 2?

Edited April 18, 2014 by Sélacien34

[Sélacien34]

Partial tooth : 1,8 cm

Cretoxyrhina mantelli?

Edited April 18, 2014 by Sélacien34

[Coco]

Hi,

How do you make to make hold your teeth up? They seem to like in the air...

Coco

[Sélacien34]

I'm magician

Edited April 19, 2014 by Sélacien34

[Sélacien34]

and look, now she's dancing and she's singing: "who am i, Am i Cretoxyrhina mantelli?" (Just photoshop work of course).

I think that she is.

Edited April 19, 2014 by Sélacien34

[siteseer]

Hi Selacien34.

Sorry about the wait.

1. Archaeolamna lateral - I have a tooth like yours from Presqu'Ile de Nemours, Saint-Dizier region, northeastern France (Middle Albian site).

2. Protolamna sp.

3. Protolamna sp. (not borodini) upper lateral.

4. Carcharias - could be C. striatula because of the short folds at the base of the crown (labial).

Jess

Hello, here some teeth from the French Albien, all Lamniforms i think, i think that i know the genus but i would need other opinions about the species, thank you.

[siteseer]

I think this one is Leptostyrax.

Jess

Another one :

4: 12 mm

[siteseer]

Hi Selacien34,

I think the first one is an unusual, early Cretodus (better known from the Cenomanian) and the second one is Archaeolamna. I'd like to see more people comment on your teeth but I know it's difficult to build a collection that includes them of this age. It's also difficult to obtain teeth from earlier in the Cretaceous..

Jess

Hi Selacien34,

I am on a business trip so I do not have access to my references at home. However, if you can take a photo of the opposite sides, and a profile photo, I will give you my opinion. Also what are the sizes? At the moment I think the first tooth is Protolamna and the second is Archaeolamna.

Did you find these teeth? Where were they collected? They are interesting. I have only a few Albian teeth from Texas and a few from France.

Jess

[Sélacien34]

Hello Jess,

Don't be sorry for the wait, i understand perfectly, i'm not at home right now either, thank you very much for the identifications, i will look at it a little more later.

[Sélacien34]

Hi Jess,

Thanks for the identifications, i agree with them. Would you have a representation of the jaws of Archaeolamna ? I'm looking for it.

About the second Archaeolamna, could it be A. aff haigi ? The base of the crown seems to be different on A. sp.

Ok for Carcharias striatula, but the lingual surface of the crown is not striated.

About the early Cretodus, (so you think that it's not a semiplicatus ?) it looks a bit like that it seems, the roots are largest but i don't have all the positions :

What do you think about the 2 last teeth that i have posted ? The first one looks like Cretoxyrhina, i think. What about the second ? Protolamna sp ?

Edited April 26, 2014 by Sélacien34

[siteseer]

No, I don't have a figure for an Archaeolamna dentition. It is a genus that ranges from the Early to Late Cretaceous and no natural dentitions are documented so it isn't always clear what you have. You have to piece together an image in your own mind from teeth from various articles and then leave room for variation. Siverson's 1992 and 1996 papers have helped me.

I don't think that tooth is haigi because i don't see folds on the lingual face.

Yes, I was unsure of the striatula identification and wondered if your tooth is worn. I could not match it to anything.

I think the "early Cretodus" tooth follows the form of Cretodus but it may be a different species from semiplicatus because it does not have lingual folds. It is difficult to say because I have seen so few Cretodus teeth. If your tooth is Cretodus, it is the oldest one I have seen

As for the last two teeth, the first one could be an early Cretoxyrhina but one that old would be expected to exhibit at least weak lateral cusplets.and your tooth seems very slender for that genus of that time. I think the second tooth could be an early Cretalamna.

Jess

Siverson, M. 1992

Biology, Dental Morphology and Taxonomy of Lamniform Sharks from the Campanian of the Kristianstad Basin, Sweden. Paleontology. Vol. 35 (3): 519-554.

Siverson, M. 1996.

Lamniform sharks of the Mid Cretaceous Alinga Formation and Beedagong Claystone, Western Australia. Palaeontology. 39 (4): 813-849.

Hi Jess,

Thanks for the identifications, i agree with them. Would you have a representation of the jaws of Archaeolamna ? I'm looking for it.

About the second Archaeolamna, could it be A. aff haigi ? The base of the crown seems to be different on A. sp.

Archaeolamna aff. haigi -.PNGArchaeolamna aff. haigi --.PNGArcheolamna sp....JPGArcheolamna sp...JPGArchaeo.PNG

Ok for Carcharias striatula, but the lingual surface of the crown is not striated.

About the early Cretodus, (so you think that it's not a semiplicatus ?) it looks a bit like that it seems, the roots are largest but i don't have all the positions :

Cretodus Albien France.jpgpost-11962-0-28523000-1397071589.jpg

What do you think about the 2 last teeth that i have posted ? The first one looks like Cretoxyrhina, i think. What about the second ? Protolamna sp ?

g.PNG

Edited April 28, 2014 by siteseer