Plesiosaur tooth Asfla Goulmima Morocco

[Jurassicz1]

I have been thinking of buying this Plesiosaur tooth but I want to be sure its real and in well condition. Its from the Asfla Goulmima in Morocco. Turonian. Seller says its 

libonectes morgani. 

[pachy-pleuro-whatnot-odon]

Provenance and age are correct. But while this is from a vendor I know to be honest, I'm not sure I agree with their identification in this case (no single vendor knows everything about all types of fossils, yet a label is required to make a sale). That's because Libonectes atlasense is an elasmosaur, meaning you'd expect the tooth to be somewhat labiolingually compressed with fine anastomosing striations, such as in the specimen below:

 

 

While, due to the fineness of the striae, it is possible that the latter have rubbed off of the tooth (as is most often the case with teeth Zarafasaura oceanis), this particular tooth is entirely smooth and shows no sign of compression. That doesn't necessarily mean the tooth isn't plesiosaurian, however, as the polycotylids of the region appear to have either fully compressed or subtrihedral teeth with (presumedly) only anterior/mesial compression, and fine striations lingually at the base of the tooth. Sometimes only the tip of the crown is found giving the false impression of an unornamented plesiosaur tooth. Unfortunately, though, I don't see any indications for any of the morphologies either...

 

Something that is often overlooked, however, is that the Akrabou Formation hasn't just yielded the remains of the primitive mosasaur Tethysaurus nopscai, the elasmosaur Libonectes atlasense, a brachauchenine pliosaur and the polycotylids Manemergus anguirostris and Thililua longicollis, but also plenty of fish remains. One of those fish is Enchodus, of which multiple species are known from the - younger - Moroccan phosphates. Teeth of Enchodus are well-known to cause confusion with plesiosaur teeth in other geographical contexts, and the same would've been the case at Goulmima. One of the defining characteristics of Enchodus gladiolus teeth is an S-shaped curve and barb towards the tooth apex (see the specimen from New Jersey below; source):

 

 

Now the posted tooth seems to have exactly such an S-curve. And while it's possible this is just an artefact of the angle in which the second photograph was taken or the way the tooth tip was set back in matrix, and there's no sign of a barb or striations, I think it would be good to approach this tooth with the necessary caution. Moreover, while I know some people believe plesiosaur teeth can have an S-curve as well, I personally have yet to come across one that can undeniably be identified as such - the more so in light of the known plesiosaur tooth morphologies at this location. This is the main reason I've forgone to buy this tooth myself, although I've been aware of it for a while...

 

Hope this helps.

[Jurassicz1]

On 11/15/2021 at 10:50 AM, pachy-pleuro-whatnot-odon said:

Provenance and age are correct. But while this is from a vendor I know to be honest, I'm not sure I agree with their identification in this case (no single vendor knows everything about all types of fossils, yet a label is required to make a sale). That's because Libonectes atlasense is an elasmosaur, meaning you'd expect the tooth to be somewhat labiolingually compressed with fine anastomosing striations, such as in the specimen below:

 

 

While, due to the fineness of the striae, it is possible that the latter have rubbed off of the tooth (as is most often the case with teeth Zarafasaura oceanis), this particular tooth is entirely smooth and shows no sign of compression. That doesn't necessarily mean the tooth isn't plesiosaurian, however, as the polycotylids of the region appear to have either fully compressed or subtrihedral teeth with (presumedly) only anterior/mesial compression, and fine striations lingually at the base of the tooth. Sometimes only the tip of the crown is found giving the false impression of an unornamented plesiosaur tooth. Unfortunately, though, I don't see any indications for any of the morphologies either...

 

Something that is often overlooked, however, is that the Akrabou Formation hasn't just yielded the remains of the primitive mosasaur Tethysaurus nopscai, the elasmosaur Libonectes atlasense, a brachauchenine pliosaur and the polycotylids Manemergus anguirostris and Thililua longicollis, but also plenty of fish remains. One of those fish is Enchodus, of which multiple species are known from the - younger - Moroccan phosphates. Teeth of Enchodus are well-known to cause confusion with plesiosaur teeth in other geographical contexts, and the same would've been the case at Goulmima. One of the defining characteristics of Enchodus gladiolus teeth is an S-shaped curve and barb towards the tooth apex (see the specimen from New Jersey below; source):

 

 

Now the posted tooth seems to have exactly such an S-curve. And while it's possible this is just an artefact of the angle in which the second photograph was taken or the way the tooth tip was set back in matrix, and there's no sign of a barb or striations, I think it would be good to approach this tooth with the necessary caution. Moreover, while I know some people believe plesiosaur teeth can have an S-curve as well, I personally have yet to come across one that can undeniably be identified as such - the more so in light of the known plesiosaur tooth morphologies at this location. This is the main reason I've forgone to buy this tooth myself, although I've been aware of it for a while...

 

Hope this helps.

Ok thanks! But is the vendor trusted?

[Kane]

Please keep questions focused on the specimen. The seller’s reputation is immaterial to answering questions about quality and authenticity.

[Jurassicz1]

34 minutes ago, Kane said:

Please keep questions focused on the specimen. The seller’s reputation is immaterial to answering questions about quality and authenticity.

Oh ok because I thought of buying other items from there. Then I can post them and ask.

[Kane]

4 minutes ago, Jurassicz said:

Oh ok because I thought of buying other items from there. Then I can post them and ask.

It is posted right in the rules for this subforum:

 

"For our educational purposes, the sellers' identity is immaterial; this is all about the specimens."

[pachy-pleuro-whatnot-odon]

36 minutes ago, Kane said:

Please keep questions focused on the specimen. The seller’s reputation is immaterial to answering questions about quality and authenticity.

 

1 minute ago, Jurassicz said:

Oh ok because I thought of buying other items from there. Then I can post them and ask.

 

While it is indeed not allowed to discuss a vendor's reputation on the forum, you can always send members a PM to ask such questions. If you do, I'd be happy to answer them for you. Or you could indeed post individual specimens to have them evaluated. It depends on the (level of) information you're looking for, so the choice is up to you

[Jurassicz1]

10 hours ago, Kane said:

It is posted right in the rules for this subforum:

 

"For our educational purposes, the sellers' identity is immaterial; this is all about the specimens."

Oh yeah must have forgot it! Sorry. Have read the rules again.