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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. 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)
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While I was sorting through my collection of croc fossils, I came across these Elrhaz Formation teeth I bought 6 months ago and never did figure out what they were. I assume they are croc and not some kind of fish, though I could be wrong. I've never seen these apart from the one source I purchased them from. I've been told they were Sarcosuchus, then Kaprosuchus, then Suchomimus. Pretty sure it's not Sarcosuchus, and the images I can find of Kaprosuchus don't seem to match. Suchomimus, I don't know, but my gut feeling is, no, I've seen dozens of Suchomimus and fake-Sucho crocs, and never found a match. If anyone is familiar with this morphology, any input is appreciated. Locale: Gaoufaoua, Tenere Desert, Niger Last picture is a couple of other crocs from the same lot. One (the robust one on the right) is probably Sarcosuchus.