Troodon Posted August 27, 2018 Share Posted August 27, 2018 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. 1 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. 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 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 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 Scale: 1 mm 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. 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 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) 8 Link to comment Share on other sites More sharing options...
Troodon Posted August 27, 2018 Author Share Posted August 27, 2018 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. 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 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. 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. 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 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. 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 Scale: 1 mm 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) 9 Link to comment Share on other sites More sharing options...
lone5wolf117 Posted August 27, 2018 Share Posted August 27, 2018 Thanks Troodon this would definately help seeing has most of the members are getting Niger tooths. Link to comment Share on other sites More sharing options...
Bobby Rico Posted August 27, 2018 Share Posted August 27, 2018 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. Link to comment Share on other sites More sharing options...
The Amateur Paleontologist Posted August 27, 2018 Share Posted August 27, 2018 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 Link to comment Share on other sites More sharing options...
CBchiefski Posted August 27, 2018 Share Posted August 27, 2018 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 2 Link to comment Share on other sites More sharing options...
Troodon Posted August 27, 2018 Author Share Posted August 27, 2018 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. 1 Link to comment Share on other sites More sharing options...
Troodon Posted August 27, 2018 Author Share Posted August 27, 2018 Updated Jurassic page Link to comment Share on other sites More sharing options...
Masp Posted August 27, 2018 Share Posted August 27, 2018 @Troodon thanks for this info Frank Link to comment Share on other sites More sharing options...
Troodon Posted August 27, 2018 Author Share Posted August 27, 2018 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... 2 Link to comment Share on other sites More sharing options...
Haravex Posted July 27, 2021 Share Posted July 27, 2021 Made a short video highlighting the differences between crocodile and suchomimus teeth as I have seen quite a few wrongly identified, hope this helps. https://www.instagram.com/p/CR2N2sfKvzH/ 1 Link to comment Share on other sites More sharing options...
Troodon Posted July 28, 2021 Author Share Posted July 28, 2021 16 minutes ago, Haravex said: https://www.instagram.com/p/CR2N2sfKvzH/ Does it require an instagrm acct to open which I dont have. Link to comment Share on other sites More sharing options...
Haravex Posted July 28, 2021 Share Posted July 28, 2021 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. Link to comment Share on other sites More sharing options...
Troodon Posted July 28, 2021 Author Share Posted July 28, 2021 1 hour ago, Haravex said: It shouldn't do anyone should be able to view this. Thanks was able to see it today 1 Link to comment Share on other sites More sharing options...
lesofprimus Posted October 17, 2021 Share Posted October 17, 2021 Most excellent post! Link to comment Share on other sites More sharing options...
Troodon Posted August 18, 2022 Author Share Posted August 18, 2022 Updated the Jurassic portion of this topic and will continue to do so as new information is discovered or published. Link to comment Share on other sites More sharing options...
Dino Dad 81 Posted September 16, 2022 Share Posted September 16, 2022 @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? Link to comment Share on other sites More sharing options...
Troodon Posted September 16, 2022 Author Share Posted September 16, 2022 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. Link to comment Share on other sites More sharing options...
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