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Kem Kem Theropod Teeth: what you need to know


Troodon

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Updated 5/4/22 (in red)

Updated 3/8/23 to add Carch photos of holotype

 

Although a lot of this has already been posted on a number of topics, I thought consolidation might prove useful with some additional information.
If you're planning to purchase theropod teeth from Morocco's Kem Kem Beds or already have some in your collection check this out.

 

Moroccan theropods are poorly understood and not a lot has been published.   Very few articulated skeletons have been found and most are partial and without a skull.  There is also lots of mis-information, mostly unintentional, from some dealers but especially with online auction sites. Unfortunately these are the most misidentified commercially sold dinosaur fossil around.  Please post your interest here on the forum before you buy.

 

These strata are recognized as the Kem Kem Group, which is composed in the south of the lower Gara Sbaa and upper Douira formations, in the North the Deckar 2 and 3 Formations and in the central region as Akrabou and Ifezouane Formations.

 

Screenshot_20201112-155500_Drive.jpg.513c1c98dc413518ed25a77e84a32b71.jpg

Quite a bit of material is has been made available to collectors from El Begaa which is the closest village to the locality Aferdou N’Chaft.     Based on Nizar Ibrahim et al. / ZooKeys 928: 1–216 (2020) publication we can say this material is from the Gara Sbaa Formation in the Kem Kem Group

 

There is also material becoming available from area 13 Iferda N'Ahouar which also appears to be the Gara Sbaa Formation.

KK2.thumb.JPG.01cb7a77b02685fc2791e001a8e5a574.JPG

 

The distribution of the different groups of fossils can been see in the pie chart below.  Dinosaurs make up a small percentage of what is collected.

 

Screenshot_20170326-083357.thumb.jpg.2ba06948da48909c55628c7218fbb893.jpg

 

 


So first lets identify what is known to the best of my knowledge.

Theropods that have been described across North Africa (focus on large bodied theropods).   Ibrahim et al. not in agreement

 

Screenshot_20170325-124003.thumb.jpg.f4d1fa791175b4d32cb67525967d3c07.jpg 

 

Theropods that have been described in Kem Kem:


>Spinosaurus aegyptiacus * (Spinosauridae) 

  *Some paleontologist believe this species is unique to Egypt and Kem Kem material should be identified as Spinosaurid indet.  Lots of questions exist over Ibrahim (2014) diagnosis which validated this species.    The question of multiple Spinosaurids is still an open issue.

>Sigilmassasaurus brevicollis  (Spinosauridae)   Validity is questioned by Ibrahim et al.

>Carcharodontosaurus saharicus  (Carcharodontosauridae)

>Sauroniops pachytholus  (Carcharodontosauridae)  Validity is questioned by Ibrahim et al.

>Deltadromeus agilis    (Neovenatoridae)


Theropods that have not been described from the Kem Kem but isolated teeth may exist and have been reflected in scientific papers:


>Dromaeosaurid sp.? Hendrickx  suggested these are actually Noasaurid indet.

>Abelisaurid indet.
 

Theropod teeth that are sold commercially but no scientific evidence yet to link them to the Kem Kem:

 

>Abelisaurus sp. (Not described from North Africa) 
>Rugops sp. (Only described from Niger)
>Bahariasaurus sp. (Only described from Egypt)
>Elaphrosaurus sp. (From Jurassic of Tanzania)

So what is being sold and what are the issues?

Spinosauridae 

Teeth are well understood by both collector and dealers, see photo. Issues are typically associated with restoration and compositing a larger tooth from multiple teeth. Teeth with matrix attached to them are suspect for restoration so be careful.  

 

At least two species of Spinosaurids exits and it's currently impossible to determine if they are Spinosaurus or Sigilmassasaurus or an Undescribed taxon.  

Conflicting taxonomic hypotheses have been proposed. Ibrahim at al (2014) suggest that all specimens found belong to Spinosaurus aegyptiacus. Evers et al (2015) regard Spinosaurus maroccanus and Sigiilmassaurus brevicollis as belonging to the same taxon S. brevicollis which is also supported by Hendrickx et al (2016).  Ever at al (2015) also described additional specimens from a second unnamed Spinosaurid.  Bottom line we do not have enough specimens to eliminate ontogenetic or sexual dimorphism differences and accurately describe Spinosaurids in the Kem Kem.

 

So these teeth are best identified as: Spinosaurid indet.  

 

Vertical ridges can be present on both lingual and labial side, or absent on both or just one side.. 
post-10935-0-09426400-1444235081_thumb.jpg

 

Serrated :  Spinosaurid teeth exist with a "beaded" carina. few examples of finely beaded teeth are popping up.  Not sure we can currently say much about them if they are an evolutionary carryover on some teeth, an abberation in some jaws or a Baryonychinae type species.

 

SpinoJaw2e.thumb.jpg.a19f1c2b13c741c342ddbc880b87c81e.jpg

 


Carcharodontosauridae

Not a lot is published on these teeth the and the best we have is from the holotype.

 

Maxilla contained a few teeth

Screenshot_20230308_062943_Drive.thumb.jpg.dbd3ad3949822fb27c5975d579feb92b.jpg

 

No teeth were found on the partial dentary

Screenshot_20230308_063003_Drive.thumb.jpg.d7f2a9201c6d713bc651ae4b34e20d4f.jpg

 

 

 

Teeth, those that are compressed and blade like, first photo.   Wrinkles by the distal carina are diagnostic to this species.  Mesial teeth are fat, slender and look very different (D shaped) (next three photos).   

 

Two species currently are described Carcharodontosaurus saharicus and Sauroniops pachytholus and its impossible to differentiate teeth between these taxons.  Similiar to the Spinosaurid debate one exists with these two species and if Sauroniops is valid.  Similiar to Spinosaurids the big issue is having enough specimens to make a proper determination in what exists.

 

 For these reasons best identified as : Carcharodontosaurid indet.
On Lateral teeth marginal and transverse undulations can be present.  Mesial carina reaches the base in most lateral teeth.   Distal serration density typically greater than mesial on lateral teeth, opposite on mesial teeth. 

Lateral tooth
post-10935-0-09932900-1444235467_thumb.jpg

 

Anterior Tooth
post-10935-0-51704100-1444235898_thumb.jpgpost-10935-0-51823300-1444235900_thumb.jpgpost-10935-0-46046400-1444240741_thumb.jpg

 

Carcharodontosaurid indet   Pre-Maxillary Tooth

From the collection of @Omnomosaurus  and identified by Christophe Hendrickx  

Serration Count: 

 Mesial: 12/5mm 

                 8/5mm (closer to apex)             

 Distal: 9/5mm (just above midline)

               7/5mm (closer to apex)

               

CH: 34mm approx, CBL: 15mm, CBW: 9.5mm, CBR: .63

 

Key Features:

  • Mesial carina ends mid-crown and is centrally placed.
  • No marginal undulations present
  • No transverse undulations present
  • No longitudinal ridges present
  • Weak short interdental sulci on one side of distal denticles at mid-cow
  • Strongly displaced distal carina
  • Braided enamel texture

 

Photos by Omnomosaurus

IMG_20190522_161435818.jpg.6284ef43115f3cfba1f1e8fee3727031.thumb.jpg.e49c2bc4a0532885bbb79a77ce38301a.jpgIMG_20190522_161326350.jpg.e186cc474137db5e11d999baf68015ac.thumb.jpg.bd2f05fe9311dad88400ce949b18c6df.jpgIMG_20190522_161743261.jpg.4dbdac8ceb08cb1dd3c1570a4bf918aa.thumb.jpg.e07eca49647de1ee579bcda5876422f3.jpgIMG_20190522_161647520.jpg.bdf45cb7cabc2d81f93e33f04e0d2eb0.thumb.jpg.d76f126797b5b367b1fee14e485b1abf.jpg

IMG_20200101_192036280.jpg.b442d3542337e0c334e28b72d42dca13.thumb.jpg.78152c3253ed54bb4980657ffde22bbc.jpgIMG_20190522_113728672.jpg.ce4ec0e2727fa01b432ed37444e4cad3.thumb.jpg.e0b78864717f7394c83784d62ebea4ef.jpg

 


Theropod indet.  

There are also intermediate size teeth (1 1/2") that are being sold as Deltadromeus or another theropod. I believe these could be Deltadromeus teeth but until we see scientific evidence this morphology of tooth should be identified as Theropod indet.  No skull was found with the holotype or in any other discoveries so we do not know what they look like.

 

post-10935-0-32795200-1444237946_thumb.jpg

Carcharodontosaurid serrations
post-10935-0-46963400-1444238029_thumb.jpg

 

Theropod indet.

post-10935-0-05703400-1444238034_thumb.jpg


Dromaeosauridae: 

Teeth being sold as Dromaeosaurus are most likely misidentified, so here is what to look for.  There are a few morphologies floating around but nothing as been formally described.  Teeth are typically small around 1/2" (1.2cm) to over 1" (2.5cm) One morphology of these teeth are suggested by Hendrickx to be from a Noasaurid dinosaur. 

 

Although you see many sellers using the word Raptor next to what they are offering it's unknown if there is a true raptor in the Kem Kem. Abelisaurids are not raptors  

 

This figure identifies a study of isolated teeth by  Richter (2015) and identifies two morphologies (A to D) and (E to G) as Dromaeosaurid.   Mesial and distal carinae show a distinct density difference in serrations. The tip of the tooth extends past the base.  On morph E/F a faint but visible constriction between crown and root is visible.   The later form suggested by some paleontologists is most similiar to troodontids.

Screenshot_20171107-051114.thumb.jpg.d304a316e4259234ca3cf2063794b849.jpg

 

Morph variant 3 that I have in my collection but not seen in any papers

Mesial and distal carinae range show a distinct difference.  A distinct twist to the mesial carina.  It's unknown what this tooth belongs to.

 

Dromie2D.thumb.jpg.8c9608fd307ea249c0a04819af8118c2.jpgDromie2F.thumb.jpg.734688b6f07a2612d85fe8ce03778bd3.jpg



 Abelisaurid indet.

With new discoveries we can put a real species name to these teeth but currently they are indeterminate.  These are easily identifiable but can easily be misidentified with certain morphologies of Dromaeosaurid teeth. The teeth are very compressed, the cross-section is oval at the base, the mesial side is strongly curved and the distal side is almost straight to the base of the tooth, see red lines in the photo.  

 

These teeth could be similar to Rugops since it's an Abelisaurid but we have no scientific information to suggest that they are and should be identified as Abelisaurid indet.     Specimen UCPC 10 is extremely similar to Nigers Rugops but its missing several characteristics that definitively say its Rugops sp.   Quite a few paleontologists have said its the same species.


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Premaxillary 

594805d31ca96_AbelT-D196E.thumb.jpg.9d5cad6c18fcc1deeff2c0aacf435195.jpg

 

 


Bottom Line:

There are NO theropod teeth in the Kem Kem Beds that you can currently definitively assign to a Genus, no less a Species, all should be identified to a family level..  

 

If your interested here are some of the variations in morphologies of teeth from the Kem Kem

 

 

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About Deltadromeus, are you suggesting that those we see in the market today are in fact misidentified, perhaps Carch teeth?

Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday!

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About Deltadromeus, are you suggesting that those we see in the market today are in fact misidentified, perhaps Carch teeth?

Many "Deltadromeus" teeth I've seen are indistinguishable from carch teeth. The name is a marketing label as no skull remains are known. Adding more to the confusing is that some studies have shown the closest relative of Deltadromeus to be Limusaurus, a toothless, herbivorous ceratosaur, so it is possible Deltadromeus was a herbivore with no teeth at all.

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Seems that this topic of Deltadromeus was heavily discussed before > http://www.thefossilforum.com/index.php?/topic/40340-difference-between-deltadromeus-carcharodontosaurus-teeth/

One of the key questions asked wasn't answered however: It seems it would be more suitable to view it more as a Moroccan/African ceratosaur. Though any teeth experts here can help clarify as to what are the key features of a ceratosaurian tooth that distinguish it from a carcharodontosaurid tooth?

Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday!

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Great post as usual. Very informative. I wasn't aware that Deltadromeus was described.

Something that might also be useful. Using photogrammetry I scanned two teeth from Kem Kem. The big plus with 3D models is that you can view them from any angle. I also plan to scan other Kem Kem teeth I have (such as Spinosaurus) so they can be used for reference.

So here are scans of a Carcharodontosaurus tooth and an Abelisaurid tooth. At least I think it's an Abelisaurid. It was sold to me as a Raptor tooth. But seeing as the caudal edge is straight and there is no great difference in the size of the serrations. I figured it can't be Raptor. (So feel free to correct me if I'm wrong and I'll fix the name.)

Carcharodontosaurus saharicus tooth

6.5 cm tall (about 2.5 inch)

 

Abelisaurid tooth

1.9 cm tall (about 3/4 inch)

 

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Olof Moleman AKA Lord Trilobite

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Very nice scans. What size are these teeth?

Edit: I think you are spot on with your ID's

Edited by Troodon
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About Deltadromeus, are you suggesting that those we see in the market today are in fact misidentified, perhaps Carch teeth?

IMO, on smaller thin ones, yes they could be but I can easily change with facts, again just my opinion. Need to keep an open mind here, there may be other Carch type species in the Kem Kem. I looked at several teeth and all their serrations were the same as Carch. Deltadromeus is currently classified as a ceratosaurian so I would have expected them to be different but they might not be. My initial post came across to strong since I don't know and because its an opinion I changed it to say these are Theropod indet.

Its also risky to use dealers as a source for ID's we need to deal in what is published or state its an opinion. Theropods in the Kem Kem are poorly understood and we need to wait to see what comes out and not be swayed by what is sold. In the end we need a skull with teeth "published" to put this to bed.

Edited by Troodon
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Very nice scans. What size are these teeth?

Edit: I think you are spot on with your ID's

Sorry I should have added that right away. for them to be the most useful. Here are the sizes in cm and inches. I've also added the sizes to the earlier post.

Carcharodontosaurus tooth

6.5 cm tall (about 2.5 inch)

Abelisaurid tooth

1.9 cm tall (about 3/4 inch)

It might also be worth mentioning crocodile teeth as those are sometimes confused with Spinosaurus.

And some dealers also sometimes claim that certain teeth are from Suchomimus. As I understand it this would be impossible since Suchomimus doesn't appear in Morocco at all and is from an earlier time period than that of Kem Kem. Teeth from Morocco that are identified as Suchomimus are probably just Spinosaurus.

Edited by LordTrilobite

Olof Moleman AKA Lord Trilobite

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Opinions on this tooth?

It was marketed as a Deltadromeus tooth, and measures over 6 inches (the guy has a huge hand).

The authenticity of the tooth is not in question; the seller comes highly recommended and the tooth has been seen by several experts. The only question is... what animal does it belong to.

post-4888-0-60037000-1444319869_thumb.jpg post-4888-0-84399400-1444319956_thumb.jpg post-4888-0-40367400-1444319959_thumb.jpg

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Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday!

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Very nice rooted tooth. In my opinion it's a Carch tooth from the front of a jaw. Just ask yourself what size skull can support that size tooth? Much too big to fit into midsize dinosaurs like Deltadromeus. Are you buying or just gawking at it. :wub:

Question? How can any seller be highly recommended if they are marketing Deltadromeus teeth that no one knows what they look like?

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I agree with Troodon. This is a Carch tooth! Judging by the shape of the tooth, round and robust rather than flat and blade like, this is what most people refer to as a premaxillary tooth. If this tooth is all original, it is very rare indeed! You do not see very many rooted teeth of any kind from Morocco that are real!

Also, like Troodon said, why is a reputable dealer describing this tooth as Deltadromeus!?

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Very nice rooted tooth. In my opinion it's a Carch tooth from the front of a jaw. Just ask yourself what size skull can support that size tooth? Much too big to fit into midsize dinosaurs like Deltadromeus. Are you buying or just gawking at it. :wub:

Question? How can any seller be highly recommended if they are marketing Deltadromeus teeth that no one knows what they look like?

I agree with Troodon. This is a Carch tooth! Judging by the shape of the tooth, round and robust rather than flat and blade like, this is what most people refer to as a premaxillary tooth. If this tooth is all original, it is very rare indeed! You do not see very many rooted teeth of any kind from Morocco that are real!

Also, like Troodon said, why is a reputable dealer describing this tooth as Deltadromeus!?

There's two schools of thoughts it seem, on Deltadromeus. One is yours, in which we don't know what Delta was like, and hence there's no actual identifiable Delta anywhere.

The other is that certain features of Moroccan teeth makes them Deltadromeus. I've not gotten a reply from the dealer yet as to why he was so certain this giant tooth he sold was a Delta not a Carch(He told me once it was tough to get the ID down, so he definitely considered Carch for this tooth at one point), but here's what George Corneille of Fossilgrove said on the subject: "Delta teeth are distinctive in they are very lateral compressed and are long and narrow,interesting point you may not know is Gabrielle Lyon who discovered Delta told me no skull was ever found with the skeleton,so id is conjecture."

Here's a pic of George's Delta tooth.

post-4888-0-00918100-1444607935_thumb.jpg post-4888-0-37289600-1444607937_thumb.jpg post-4888-0-87879800-1444607938_thumb.jpg post-4888-0-10291200-1444607940_thumb.jpg

This dealer seem to have

Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday!

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There's two schools of thoughts it seem, on Deltadromeus. One is yours, in which we don't know what Delta was like, and hence there's no actual identifiable Delta anywhere.

The other is that certain features of Moroccan teeth makes them Deltadromeus. I've not gotten a reply from the dealer yet as to why he was so certain this giant tooth he sold was a Delta not a Carch(He told me once it was tough to get the ID down, so he definitely considered Carch for this tooth at one point), but here's what George Corneille of Fossilgrove said on the subject: "Delta teeth are distinctive in they are very lateral compressed and are long and narrow,interesting point you may not know is Gabrielle Lyon who discovered Delta told me no skull was ever found with the skeleton,so id is conjecture."

Here's a pic of George's Delta tooth.

attachicon.gif10844389_10203877059305268_820723212_o.jpg attachicon.gif10854133_10203877058825256_1365845615_o.jpg attachicon.gif10860771_10203877058865257_1758445882_o.jpg attachicon.gif10864394_10203877059265267_2110692168_o.jpg

This dealer seem to have

I'm just curious as to why you wouldn't think this type of tooth isn't just a juvenile Carcharodontosaurus. Just because it's a smaller tooth, does it have to be a different species?

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I love the fact that some dealers have the knowledge to identify their teeth as Deltadromeus and have become theropod experts on Moroccan teeth. The real experts don't even want to speculate on what they look like until they see a skull!

I made this point before but think about the size of skull needed to house that 6" tooth. It's what would expect to find in a sub-adult T-rex or an equivalent size theropod in the Kem Kem like Carcharodontosaurus. The attached photo is National Geographic rendition of Deltadromeus at their Spinosaurus exhibit. Not a lot of room in that skull for a 6" tooth.

post-10935-0-21183500-1444610113_thumb.jpg

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The interesting thing is that in the past, George told me he needs to see many close-ups of my "Delta" teeth in different angles before he can tell if it's a real Delta or a Carch tooth.

I'm also waiting for his reply in what exactly helps him distinguish between them. I consider George to be extremely knowledgeable, especially in Moroccan fossils as his papers on Moroccan Mosasaurs were published before.

Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday!

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Until a skull of Deltadromeus is found I am very uncomfortable assigning any teeth to them with certainty. In my opinion though, if any teeth are referred to as Deltadromeus, they should be the smaller very thin blade like teeth that are under an inch long not these larger teeth that are probably just juvenile Carchs.

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Until a skull of Deltadromeus is found I am very uncomfortable assigning any teeth to them with certainty. In my opinion though, if any teeth are referred to as Deltadromeus, they should be the smaller very thin blade like teeth that are under an inch long not these larger teeth that are probably just juvenile Carchs.

Wouldn't these small very thin ones be too small for Delta? I have several of these and they appear to be like an average Dromeosaur tooth. Not a tooth belonging to a 26 foot long ceratosaur. Much too small in my opinion. I don't think we can properly identify and assign teeth to this species until skull material is found. It sure does make a good market for dealers that can't put an ID on a theropod tooth from Morroco though.

Edited by Runner64
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Wouldn't these small very thin ones be too small for Delta? I have several of these and they appear to be like an average Dromeosaur tooth. Not a tooth belonging to a 26 foot long ceratosaur. Much too small in my opinion. I don't think we can properly identify and assign teeth to this species until skull material is found. It sure does make a good market for dealers that can't put an ID on a theropod tooth from Morroco though.

I'm thinking though, if we can find a defining feature for this group of unidentified teeth, then they do deserve a name of their own, even if temporary.

Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday!

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Well there is rebbachisaurus. A sauropod. But there does seem to be a certain lack of herbivores.

Though, it was mostly river delta at the time. Maybe the herbivores just didn't fancy a swim in waters where Spinosaurus lurked. :D

Olof Moleman AKA Lord Trilobite

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That's a question I've wondered for a long time. I have never seen any teeth or bones, other than sauropods, at the Tucson show with all the Morrocan dealers around. Herbivores typically make up a high percentage of a fauna. They are one of the food sources for theropods. Carch, Delta, Abelisaurids had to prey on some animals other than sauropods maybe not??

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Mayhap there was just ALOT of fish to eat there?

On a related note, is there conclusively only one species of pterosaur from Kem Kem?

Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday!

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