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Identification of Theropod Teeth from Niger


Troodon

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REVISED 4/8/23

Before I discuss the identification of teeth from the Republic of Niger I would like to raise the red flag on material from this region.   A late 2022 publication ( Yohan POCHAT-COTTILLOUX et al.), Microvertebrate fauna from Gadoufaoua, highlighted a concern I was not previously aware of.   The deposits in this area are adjacent to each other as these illustrations show.  This why the deposits are probably more appropriately identified as the Tegama and Irhazer Group.   A research group that conducted the study is clearly aware of the deposits but how local diggers can they determine if a tooth comes from the Jurassic Irhazer Shale or Tiourarén Fm or can they distinguish between the Cretaceous the Echkar or Elrhaz Fm.  Can they even distinguish between Jurassic and Cretaceous deposits.  Material then is consolidated with a local person who,  identifies and then probably distributes the material to sellers.  Bottom line, I not sure how accurate the provenance of this material is when offered for sale.   I would be very cautious with the purchase of this material since a Gadoufaoua can describe many different deposits.

 

1Screenshot_20230408_134919_Drive.thumb.jpg.942a97e6c43941fad818d3d814966475.jpg

 

 

Identication of Theropod teeth from the Republic of Niger is not easy.  In addition to the lack of publications, few specimens exists that we can compare against so its going to be an uphill battle.  Plan to post what is available in publications.  All assistance is appreciated but needs to be from a published/scientific source but this is a start.

 

Pictures are not adequate in themselves to identify some of these teeth so  have to rely on looking at the characteristics of a tooth.  

 

Terminology to help us in the identification process. 

Screenshot_20180825-091331.thumb.jpg.02e3adf5793d5edf03ca03cb0934b64d.jpgScreenshot_20180825-091437.thumb.jpg.275dea76dd5fdba037fb96fa2c90f527.jpg

Journal of Vertebrate Paleontology :

A proposed terminology of theropod teeth (Dinosauria, Saurischia)

Christophe Hendrickx, Octávio Mateus & Ricardo Araújo

Article: e982797 | Received 07 Dec 2013, Accepted 22 Sep 2014, Published online: 01 Sep 2015

https://doi.org/10.1080/02724634.2015.982797

 

Important ratios:

Crown Base Ratio (CBR): CBR = CBW ÷ CBL

Crown Height Ratio (CHR):  CHR = CH ÷ CBL

 

 

 

Eocarcharia dinops

Carcharodontosauridae

Elrhaz Formation (Aptian–Albian, ca. 112 Ma)

Locality: Gadoufaoua

Tooth: 

CBR: .46 , CHR: 2.0

 

C Hendrickx study one tooth Distal 16 / 5 mm, Mesial 14 / 5 mm, DSDI : 1.09

 

Carinae on both edges extend to the base

Note: Density variations can occur across the dentition

Screenshot_20180825-085253.thumb.jpg.5b7bc359fc6453790390f3ba51017f8c.jpg

 

Sereno, P.C. and Brusatte, S.L. 2008. Basal abelisaurid and carcharodontosaurid theropods from the Lower Cretaceous Elrhaz Formation of Niger. Acta Palaeontologica Polonica 53 (1): 15–46.

 

 

 

Kryptops palaios

Abelisauridae

Elrhaz Formation (Aptian–Albian, ca. 112 Ma)

Locality: Gadoufaoua

Tooth: 

CBR: .6

Distal Density : 15 per 5 mm 

Serrations:  hooked apically 

Very compressed 

Only Unerupted replacement teeth are known

Screenshot_20180825-090245.jpg.d804b1d8a259c5057254dba25d69f39f.jpg

 

Sereno, P.C. and Brusatte, S.L. 2008. Basal abelisaurid and carcharodontosaurid theropods from the Lower Cretaceous Elrhaz Formation of Niger. Acta Palaeontologica Polonica 53 (1): 15–46.

 

Notes: 1) Morphology reminds me of what we see from the Kem Kem

             2) Hooked serrations of similar form are present in Rugops.

             3) Density similar to Kem Kem but finer than Rugops

 

 

 

Suchomimus tenerensis

Spinosauridae (Baryonychinae)

Elrhaz Formation (Aptian–Albian, ca. 112 Ma)

Locality: Gadoufaoua

Tooth:

Features: 

Density: 6 mm

Small marginal serrations

Textured, granular enamel

Subcylindrical in shape (conical)

Longitudinal fluting and or faceting 

Screenshot_20180827-044241.jpg.d770285bd00cc281d9d31b8125ca052e.jpgScreenshot_20180827-042609_20180827043023078.jpg.938008b89fec099a31ceedb9e41e964e.jpg

Scale: 1 mm

Screenshot_20180827-050038.jpg.944a76f2d61aed970f7595b2a3f89851.jpg

 

Sereno, P.C.; Beck, A.L.; Dutheil, D.B.; Gado, B.; Larsson, H.C.E.; Lyon, G.H.; Marcot, J.D.; Rauhut, O.W.M.; Sadleir, R.W.; Sidor, C.A.; Varricchio, D.D.; Wilson, G.P; Wilson, J.A. (1998). "A long-snouted predatory dinosaur from Africa and the evolution of spinosaurids". Science. 282 (5392): 1298–1302. Bibcode:1998Sci...282.1298S. doi:10.1126/science.282.5392.1298

 

 

 

Rugops primus

Abelisauridae

Echkar Formation (Cenomanian ca. 95 Ma)

Locality: Near Abangharit

Tooth:

Serration Density: 10 per 5 mm

Serrations:  hooked apically 

 

No isolated teeth were reported with Holotype.   The only visual I can find of these teeth are the partially erupted teeth in the maxilla see illustration.

 

Screenshot_20180825-112944.thumb.jpg.3757c686901ffd7ece0da4e8f03598ff.jpg

 

New dinosaurs link southern landmasses in the Mid–Cretaceous

Paul C. Sereno, Jeffrey A. Wilson, Jack L. Conrad

Published 7 July 2004.DOI: 10.1098/rspb.2004.2692

 

Note: Only known from a partial skull and believed not to be an adult.  

 

 

 

Carcharodontosaurus iguidensis

Carcharodontosauridae

Echkar Formation (Cenomanian ca. 95 Ma)

Locality: Abangharit in an area known as Iguidi

Tooth:

Serration Density:

Distal: 16 per 5 mm at tip, and 10 at base

Mesial: 13 per 5 mm at tip, 9 at base

Features:

Enamel wrinkles on crown

Carinae on both edges extend to the base

 

Denticles of C. saharicus

Screenshot_20180827-042609.jpg.d6cca29f0c3c8f832b7847e66c396aae.jpg

Screenshot_20180827-032352.jpg.076be0090e0f2a50a91d35667d91a3b1.jpg

 

Brusatte, S.L. and Sereno, P.C. (2007). "A new species of Carcharodontosaurus (dinosauria: theropoda) from the Cenomanian of Niger and a revision of the genus." Journal of Vertebrate Paleontology, 27(4)

 

Note: Crowns very similar to Carcharodontosaurus saharicus 

 

 

 

Spinosaurus indet., Sigilmassasaurus sp.  (Note 2)

Spinosauridae

Echkar Formation (Cenomanian ca. 95 Ma)

 

Teeth: Should be typical of Spinosaurids found in the Kem Kem Beds

 

Notes:

 1) These two are considered as synonyms by some authors and distinct by other.

 2) Mentioned existence in paper by Chiarenza & Cau (2016) 

 

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Updated 9/18/22

 

Information published in Soto et al. (2020) paper provides new insight and clarification with Serrano-Martínez et al. (2015) paper and suggested a very different assignment than what was ascribed in that paper.  I've updated the key features on the affected teeth and point out that we still have very little information to go on.   

I also question how good the provenance is with teeth identified as being from the Tiourarén Fm.   The Irhazer Shale is also present and underlies the Tiourarén Fm an older deposit.  

 

I caution to buy at you own risk we have very little information to go on that accurately identifies these teeth especially Ceratosaurid type teeth.

 

With these concerns I will not address any identification questions on jurassic material from this region.

 

Key Points of the paper:

  • The age of the Tiouraren Formation has been uncertain, originally believed to be early cretaceous and later interpreted as mid Jurassic (Bathonian).   The paper makes the following comment "The presence of a ceratosaurid proposed herein, if confirmed, would be another evidence to consider a Late Jurassic, instead of a Middle Jurassic age"
  • Serrano-Martínez et al. (2015) paper ascribes specimen TP4-2 and 3 to a Spinosauridae based on morphology not multivariate analysis.  The paper makes the following comment "We propose here ceratosaurid affinities for TP4-2 (which was tested in multivariate analyses), whereas TP4-3 may belong not to a dinosaur but to a crocodyliform, due to its lingual curvature.  :shakehead: wow 
  • Comment: "Taken into account that no definitive Jurassic spinosaurid teeth are known and that the timing and novelty sequence of apomorphic characters are unknown, we advocate for cautious assignment of spinosaurid teeth and speculate on the morphology of hypotethical spinosaurid transitional teeth in order to help in their correct identification"

 

 

 

Tiourarén Formation

Afrovenator abakensis

Meglosauridae 

Tiourarén Formation (Bathonian? ca. 167 Ma) 

Locality:   Abaka, Agadez Niger

Tooth:

CBR: .42 for Lateral Teeth

Mesial Density: 2 per 1 mm. E7 in photo

Distal Density : 3 per 1 mm E8 in photo

Mesial Carina extends down from the apex half to 2/3 of the crown.

Mesial denticles apically inclined. E7 in photo

Screenshot_2018-08-30-03-23-22.thumb.jpg.abb04f8ae80378ead122f45dbb955d21.jpg

Sereno, P.C.; Wilson, J.A.; Larsson, H.C.; Dutheil, D.B.; Sues, H.D. (1994). "Early cretaceous dinosaurs from the Sahara". Science. 266 (5183): 267–271. doi:10.1126/science.266.5183.267

 

 

Ceratosaurid..... ???????

(Very different morphology than those from other geographic localities Morrison and Lourinhã Formations)

Ceratosauridae 

Tiourarén Formation (Bathonian ? ca. 167 Ma) 

Locality:   Aderbissinat, Agadez Niger

Tooth:

CBR: .46 , CHR: 1.96

Mesial Density: 13 per 5 mm

Distal Density : 12 per 5 mm

Mesial Carina extends down from the apex half to 2/3 of the crown.

 

Screenshot_20180827-070811.jpg.d9e27672367afc1c1ec1bb1b4402bb48.jpg

Scale: 1 cm

 

Meglosaurid....possible Afrovanator abakensis

Meglosauridae

Tiourarén Formation (Bathonian ? ca. 167 Ma) 

Locality:  Aderbissinat, Agadez Niger

Tooth:

CBR: .64 , CHR: 2.14

Mesial Density: 11 per 5 mm

Distal Density : 9.5 per 5 mm

Mesial Carina extends down from the apex half to 2/3 of the crown.

 

Screenshot_20180827-072850.jpg.e20b9a05e641bea37ff888be3484ec52.jpg

Scale: 1 cm

 

Meglosaurid....possible Afrovanator abakensis

Meglosauridae

Tiourarén Formation (Bathonian ? ca. 167 Ma) 

Locality:  Aderbissinat, Agadez Niger

Tooth:

CBR: .52 , CHR: 2.33

Mesial Density: 10 per 5 mm

Distal Density : 11 per 5 mm

Mesial Carina extends down from the apex half to 2/3 of the crown.

Enamel wrinkles  on distal edge

 

Screenshot_20180827-072940.jpg.099f5ef990003697ae1e64bb17de991a.jpg

Scale: 1cm

 

 

Meglosaurid indet.

Meglosauridae??

Tiourarén Formation (Bathonian ? ca. 167 Ma) 

Locality:  Aderbissinat, Agadez Niger

Tooth:

CBR: .67, CHR: 2.79

Mesial Density: 8 per 5 mm

Distal Density : 8 per 5 mm

Mesial Carina extends down from the apex half to 2/3 of the crown.

 

Screenshot_20180827-090041.thumb.jpg.497011d38af9f7da7fed3a7d762d33c6.jpg

Scale: 1 cm

 

 

 

Spinosaurid indet.  

affinities to a Ceratosaurid. 

 

Tiourarén Formation (Bathonian? ca. 167 Ma) 

Locality:  Aderbissinat, Agadez Niger

Tooth:

CBR: .69, CHR: 1.67

Key Features on Mesial Teeth:   

 

Please note this is from a limited number of specimens

  • Base: Subcircular to lanceolate
  • Shape: Straight or slightly recurved
  • CBR: 0.57- 0.78 
  • CH: 32 - 44mm
  • Mesial Carina: Straight
  • Distal Carina: Labially displaced
  • Flutes: Present lingual side
  • Enamel Texture: Braided
  • Interdenticular sulci: can be present and short
  • Density: distal: 12 / 5mm, Mesial: absent
  • Distal serration:  chisel shaped

 

 

Texture

Screenshot_20180827-083424.jpg.c78cd5603564d25456d03edb05111703.jpg

Scale: 1 mm

 

Screenshot_20180827-082837.jpg.a8983b450851ddfd3da443a821f1fcb3.jpg

Scale: 1 cm

 

 

1)New theropod remains from the Tiourarén Formation (?Middle Jurassic, Niger) and their bearing on the dental evolution in basal tetanurans

Serrano-Martínez, Alejandro ; Ortega, Francisco ; Sciscio, Lara ; Tent-Manclús, José Enrique ; Fierro Bandera, Ignacio ; Knoll, Fabien

Proceedings of the Geologists' Association, February 2015, Vol.126(1), pp.107-118

 

 

2) Ceratosaurus (Theropoda, ceratosauria) teeth from the Tacuarembó formation (Late Jurassic, Uruguay) Matías Soto, Pablo Toriño, Daniel Perea (2020)

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Great work Frank thank you I have seen lots of these Theropod teeth sold in the uk but I think most of them are croc teeth. 

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Thanks for this :) It's not that often that we hear of Niger theropods, right?

-Christian

Opalised fossils are the best: a wonderful mix between paleontology and mineralogy!

 

Q. Where do dinosaurs study?

A. At Khaan Academy!...

 

My ResearchGate profile

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I would highly suggest you also add information from:
New theropod remains from the Tiourarén Formation (?Middle Jurassic, Niger) and their bearing on the dental evolution in basal tetanurans

Serrano-Martínez, Alejandro ; Ortega, Francisco ; Sciscio, Lara ; Tent-Manclús, José Enrique ; Fierro Bandera, Ignacio ; Knoll, Fabien

Proceedings of the Geologists' Association, February 2015, Vol.126(1), pp.107-118

 

It has some of the most up to date information on theropod teeth from that general area and many great figures. @Troodon

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3 minutes ago, CBchiefski said:

I would highly suggest you also add information from:
New theropod remains from the Tiourarén Formation (?Middle Jurassic, Niger) and their bearing on the dental evolution in basal tetanurans

Serrano-Martínez, Alejandro ; Ortega, Francisco ; Sciscio, Lara ; Tent-Manclús, José Enrique ; Fierro Bandera, Ignacio ; Knoll, Fabien

Proceedings of the Geologists' Association, February 2015, Vol.126(1), pp.107-118

 

It has some of the most up to date information on theropod teeth from that general area and many great figures. @Troodon

Thank you Im aware of that and currently working  on it.

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3 hours ago, The Amateur Paleontologist said:

It's not that often that we hear of Niger theropods, right?

Lately getting lots of inquiries about them why I developed the topic.  Not very common material but like the Kem Kem often misidentified...

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  • 4 months later...
13 hours ago, Troodon said:

Does it require an instagrm acct to open which I dont have.

It shouldn't do anyone should be able to view this.

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1 hour ago, Haravex said:

It shouldn't do anyone should be able to view this.

Thanks was able to see it today 

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  • 2 months later...
  • 2 months later...

Updated the Jurassic portion of this topic and will continue to do so as new information is discovered or published.  

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  • 4 weeks later...

@Troodon

I'm surprised that the mesial carina on ceratosaurids in the region aren't extending to the base. That seemed like an important characteristic for IDing lateral Ceratosaurus in the Morrison fm. Am I understanding correctly? Has it just become very difficult to distinguish between megalosaurs and ceratosaurs in Niger?

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Sorry for late responses  driving to SD.

I was puzzled at that and yes very hard to distinguish between the two.  Hendrickx paper says most should reach the cervix on Morrison Ceratosaurs but the morphology of Niger ones is very different.  Our level of understanding of the Niger Ceratosaurids is very limited with just a few examples.  So I would purchase a tooth if you like it.  At some point we are going we will get a better definition of the morphology.

 

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