Is it possible to ID these shark and mosasaur teeth?

[PossumTeacher]

Hi, everyone. Hope you are well and healthy!

 

Would it be possible to narrow down the identification of these teeth (pictures below)?

 

The shark tooth, from ~40-65 Ma (Paleogene, Paleocene/Eocene), Khouribga (Morocco), came without any label from the seller, but I suspect it might be a Cretolamna sp. (or Brachycarcharias ?atlasi) specimen, though I'm not entirely sure.

 

As for the mosasaur teeth, I was wondering if they might belong to two different species, although I’m aware that mosasaurs had heterodonty. They are labeled as Prognathodon sp. from the Maastrichtian (~66 Ma), Oued Zem, Khouribga, Morocco (Ouled Abdoun Basin). However I understand that the genus needs a thorough taxonomic revision, I was hoping someone could help confirm if they belong to different species, verify that they are indeed Prognathodon specimens, and/or narrow down the identification to the species level. My guess is that one tooth (or two teeth) could be the median or back tooth of Thalassotitan atrox and the other two (or other one) could be median teeth from Prognathodon currii.

 

Additionally, is it possible to determine with any certainty which part of the jaw these teeth (both shark and mosasaurs) came from?

 

Sorry for the blurry pictures, it was the best I could take in this zoom

 

Thanks so much for any help!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited September 7 by PossumTeacher
spacing and blurry pictures

[PossumTeacher]

After further study, I've concluded that the shark tooth can be identified as "cf. Serratolamna maroccana Arambourg, 1935", and the mosasaur teeth (all three) as "Prognathodon cf. currii Christiansen & Bonde, 2002". Below, I've listed the key resources I used to support these identifications, although I have consulted several additional materials. I hope this helps other people in the future!

 

• Shark:
  • http://www.elasmo.com/frameMe.html?file=genera/cretaceous/cretalamna.html&menu=bin/menu_genera-alt.html
  • http://www.elasmo.com/frameMe.html?file=genera/genera.html&menu=bin/menu_genera-alt.html
  • https://www.thefossilforum.com/topic/144695-is-it-possible-to-id-these-shark-and-mosasaur-teeth/
  • https://www.thefossilforum.com/topic/112925-any-tips-to-differentiating-cretodus-and-cretolamna-teeth/
  • https://www.thefossilforum.com/topic/120533-otodus-cretolamna-serratalamna-or-something-else/
  • https://www.thefossilforum.com/topic/144246-cretaceous-teeth-id/
  • https://www.thefossilforum.com/topic/94940-cretolamna-sp/
  • https://www.thefossilforum.com/topic/92624-shark-tooth-id-help-cretolamna-sp-appendiculata-or-otodus-obliquus/
  • https://www.thefossilforum.com/topic/120330-moroccan-shark-teeth/
  • https://www.thefossilforum.com/topic/70605-morocco-shark-tooth/
  • https://www.thefossilforum.com/topic/124702-carcharocles-or-otodus
  • https://www.thefossilforum.com/topic/123876-fossil-shark-teeth
  • https://www.thefossilforum.com/topic/135984-a-shark-tooth-from-my-collection-a-cretalamna-maroccana-specimen/
  • BAZZI, Mohamad et al.. (2021). Tooth morphology elucidates shark evolution across the end-Cretaceous mass extinction. PLoS Biology, 19(8):e3001108.
  • O'LEARY, Maureen A. et al.. (2019). Stratigraphy and paleobiology of the Upper Cretaceous-Lower Paleogene sediments from the Trans-Saharan Seaway in Mali. Bulletin of the American Museum of Natural History, n° 436.
  • CAPETTA, Henri; NOLF, Dirk. (2005). Révision de quelques Odontaspididae (Neoselachii: Lamniformes) du Paléocène et de l’Eocène du Bassin de la mer du Nord. Bulletin de l'institut Royal des Sciences Naturelles de Belgique, Sciences de la Terre, 75:237-266.

 

• Mosasaur:
  • https://www.thefossilforum.com/topic/144695-is-it-possible-to-id-these-shark-and-mosasaur-teeth/
  • https://www.thefossilforum.com/topic/141892-some-notes-on-the-mosasaurs-of-the-world/
  • https://www.thefossilforum.com/topic/57685-mosasaur-tooth-id/
  • https://www.thefossilforum.com/topic/121787-mosasaur-tooth-crowns-id/
  • https://www.thefossilforum.com/topic/115120-prognathodon-anceps-vs-prognathodon-giganteus-what-is-the-difference/
  • https://www.thefossilforum.com/topic/143924-is-it-possible-to-identify-which-species-of-prognathodon-this-tooth-belongs-to/
  • https://www.thefossilforum.com/topic/142455-is-prognathodon-currii-in-morocco-really-prognathodon-currii/
  • https://www.thefossilforum.com/topic/143334-can-anyone-identify-this-mosasaur-tooth-it-comes-from-oulad-abdoun-basin-morocco-and-measure-77cm-which-is-huge/
  • CALDWELL, Michael W.. (2012) A challenge to categories: “What, if anything, is a mosasaur?”. Bulletin de la Société Géologique de France, 183(1): 7-34.
  • BARDET, Nathalie et al.. (2014). Mosasaurids (Squamata) from the Maastrichtian Phosphates of Morocco: Biodiversity, palaeobiogeography and palaeoecology based on tooth morphoguilds. Gondwana Research, 27(3): 1068-1078.
  • CAPETTA, Henri et al.. (2014). Marine vertebrate faunas from the Maastrichtian phosphates of Bengu´erir (Ganntour basin, Morocco): biostratigraphy, palaeobiogeography and palaeoecology. Palaeogeography, Palaeoclimatology, Palaeoecology, 409:217-238.
  • CHRISTIANSEN, Per; BONDE, Niels. (2002). A new species of gigantic mosasaur from the Late Cretaceous of Israel. Journal of Vertebrate Paleontology, 22(3):629-644.
  • LONGRICH, Nicholas R. et al.. (2022). Thalassotitan atrox, a giant predatory mosasaurid (Squamata) from the upper Maastrichtian phosphates of Morocco. Cretaceous Research, 140(105315).
  • EL-KHEIR, Gebely A. A. et al.. (2023). A Prognathodontin Mosasaur from the Maastrichtian of the Dakhla Oasis, Western Desert, Egypt. Fossil Studies, 1:60-75.

[Othniel C. Marsh]

The shark tooth is likely Cretalamna sp. as opposed to Serratolamna maroccana. Cretalamna-type teeth have by some publications been assigned to Serratolamna in the past. Some examples of Serratolamna teeth can be found here. The taxonomy of both genera, both internally and externally, have a long and convoluted history, and neither have been properly reformed, hence I haven't provided a species-level identification for the tooth. A brief discussion of this matter can be found here.

 

Whilst I'm far from a mosasaur expert myself, your teeth would not appear to be those of P. currii, though they may well belong to another Prognathodon species. An extensive discussion of Moroccan mosasaur teeth can be found here.