A new Late Viséan ammonoid assemblage from the Anti-Atlas (Early Carboniferous, Morocco)
Abstract
A new, unusually composed Late Viséan ammonoid assemblage is described from the Gara el Itima (eastern Anti-Atlas, Morocco). In addition to the species Goniatites rodioni, the assemblage includes very large specimens of Merocanites and specimens of the new genus Xenoglyphioceras gen. nov., which is interpreted to occupy a phylogenetic position between Beyrichoceras and Ferganoceras. The new species Merocanites consequius sp. nov. and Xenoglyphioceras eidos gen. et sp. nov. are described.
References
Becker R.T. & House M.R. 2000. Devonian ammonoid zones and their correlation with established series and stage boundaries. Courier Forschungsinstitut Senckenberg 220: 113–151.
Bisat W.S. 1934. The goniatites of the Beyrichoceras zone in the north of England. Proceedings of the Yorkshire Geological Society 22: 280–309. https://doi.org/10.1144/pygs.22.4.280
Böhm R. 1935. Études sur les Faunes du Dévonien superieur et du Carbonifère inférieur de la Montagne Noire. La Charité, Montpellier.
de Koninck L.G. 1880. Faune du Calcaire Carbonifère de la Belgique, deuxième partie, Genres Gyroceras, Cyrtoceras, Gomphoceras, Orthoceras, Subclymenia et Goniatites. Annales du Museé royal d’Histoire naturelle de Belgique 5: 1–333. https://doi.org/10.5962/bhl.title.149304
Delépine G. 1941. Les goniatites du Carbonifère du Maroc et des confins Algéro-Marocains du sud (Dinantien-Westphalien). Notes et Mémoires du Service géologique 56: 1–111.
Dzik J. 1997. Emergence and succession of Carboniferous conodont and ammonoid communities in the Polish part of the Variscan sea. Acta Palaeontologica Polonica 42: 57–170.
Ebbighausen V., Korn D. & Bockwinkel J. 2010. The ammonoids from the Dalle à Merocanites of Timimoun (Late Tournaisian–Early Viséan; Gourara, Algeria). Fossil Record 13: 153–202. https://doi.org/10.5194/fr-13-153-2010
Foord A.H. 1900. Monograph on the Carboniferous Cephalopoda of Ireland. Part III. Containing the families Tainoceratidæ, Trigonoceratidæ, Triboloceratidæ, Rineceratidæ, Coloceratidæ, and Solenocheilidæ (in part). Monographs of the Palaeontographical Society 54: 49–126. https://doi.org/10.1080/02693445.1900.12035492
Holzapfel E. 1889. Die Cephalopoden-führenden Kalke des unteren Carbon von Erdbach-Breitscheid bei Herborn. Palaeontologische Abhandlungen, Neue Folge 5: 1–74.
Klug C., Döring S., Korn D. & Ebbighausen V. 2006. The Viséan sedimentary succession at the Gara el Itima (Anti-Atlas, Morocco) and its ammonoid faunas. Fossil Record 9: 3–60. https://doi.org/10.5194/fr-9-3-2006
Klug C., Korn D., Landman N.H., Tanabe K., De Baets K. & Naglik C. 2015. Describing ammonoid conchs. In: Klug C., Korn D., De Baets K., Kruta I. & Mapes R.H. (eds) Ammonoid paleobiology: from macroevolution to paleogeography. Topics in Geobiology 44: 3–24. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-9630-9_1
Korn D. 2006. Ammonoideen. Schriftenreihe der Deutschen Gesellschaft für Geowissenschaften 41: 147–170.
Korn D. 2010. A key for the description of Palaeozoic ammonoids. Fossil Record 13: 5–12. https://doi.org/10.1002/mmng.200900008
Korn D. & De Baets K. 2015. Biogeography of Paleozoic Ammonoids. In: Klug C., Korn D., De Baets K., Kruta I. & Mapes R.H. (eds) Ammonoid paleobiology: from macroevolution to paleogeography. Topics in Geobiology 44: 145–161. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-9633-0_6
Korn D. & Feist R. 2007. Early Carboniferous ammonoid faunas and stratigraphy of the Montagne Noire (France). Fossil Record 10: 99–124. https://doi.org/10.5194/fr-10-99-2007
Korn D. & Klug C. 2015. Paleozoic Ammonoid Biostratigraphy. In: Klug C., Korn D., De Baets K., Kruta I. & Mapes R.H. (eds) Ammonoid paleobiology: from macroevolution to paleogeography. Topics in Geobiology 44: 299–328. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-9633-0_12
Korn D. & Klug C. 2023. Early Carboniferous coiled nautiloids from the Anti-Atlas (Morocco). European Journal of Taxonomy 885: 156–194. https://doi.org/10.5852/ejt.2023.885.2199
Korn D. & Tilsley J.W. 2006. Ammonoid assemblages from the Asbian B2b (Early Carboniferous: Mississippian) buildups of the Peak District, England. Proceedings of the Yorkshire Geological Society 56: 111–150. https://doi.org/10.1144/pygs.56.2.111
Korn D., Klug C. & Mapes R.H. 1999. Visean and Early Namurian Ammonoids from the Tafilalt (Eastern Anti-Atlas, Morocco). Abhandlungen der Geologischen Bundesanstalt 54: 345–375.
Korn D., Bockwinkel J. & Ebbighausen V. 2007. Tournaisian and Viséan ammonoid stratigraphy in North Africa. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 243: 127–148. https://doi.org/10.1127/0077-7749/2007/0243-0127
Korn D., Titus A.L., Ebbighausen V., Mapes R.H. & Sudar M.N. 2012. Early Carboniferous (Mississippian) ammonoid biogeography. Geobios 45: 67–77. https://doi.org/10.1016/j.geobios.2011.11.013
Krebs W. 1968. Die Lagerungsverhältnisse des Erdbacher Kalkes (Unterkarbon II) bei Langenaubach-Breitscheid (Rheinisches Schiefergebirge). Geotektonische Forschungen 28: 72–103.
Kullmann J. 1963. Die Goniatiten des Unterkarbons im Kantabrischen Gebirge (Nordspanien). II. Paläontologie der U.O. Prolecanitina Miller & Furnish. Die Altersstellung der Faunen. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 116: 269–324.
Librovitch L.S. 1957. O nekotorykh novykh gruppakh goniatitov iz kamennougolnykh otlozheniy SSSR. Ezhegodnik Vsesoyuznogo Paleontologicheskogo Obshchestva 16: 246–273.
Malinky J.M. & Mapes R.H. 1982. A new ferganoceratin ammonoid from the Mississippian (Lower Chesterian) of Arkansas. Journal of Paleontology 56: 308–314.
McKinney M.L. 1990. Classifying and analysing evolutionary trends. In: McNamara K.J. (ed.) Evolutionary Trends: 28–58. Belhaven Press, London.
McNamara K.J. 1986. A guide to the nomenclature of heterochrony. Journal of Paleontology 60: 4–13. https://doi.org/10.1017/S0022336000021454
Nemyrovska T., Perret-Mirouse M. & Weyant M. 2006. The early Viséan (Carboniferous) conodonts from the Saoura Valley, Algeria. Acta Geologica Polonica 56: 361–370.
Pareyn C. 1961. Les Massifs Carbonifères du Sahara Sud-Oranais. Tome II. Paléontologie stratigraphique. Publications du Centre de Recherches sahariennes, Série Géologie 1: 1–244.
Popov A.V. 1968. Vizeyskie ammonoidei cevernogo Tyan-Shanya i ikh stratigraficheskoe zhachenie. Tyan’Shanya Akademiya Nauk Kirgizkoy SSR, Institut Geologii: 1–116.
Riley N.J. 1996. Mid-Dinantian ammonoids from the Craven Basin, northwest England. Special Papers in Palaeontology 53: 1–87.
Ruzhencev V.E. & Bogoslovskaya M.F. 1971. Namyurskiy etap v evolyutsii ammonodey. Rannenamyurskiye ammonoidei. Trudy Paleontologicheskogo Instituta Akademiya Nauk SSSR 133: 1–382.
Schindewolf O.H. 1951. Über ein neues Vorkommen unterkarbonischer Pericyclus-Schichten im Oberharz. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 93: 23–116.
Schmidt H. 1941. Eine neue Fauna mit Pericyclus von Riefensbeek im Harz. Jahrbuch der Reichsstelle für Bodenforschung 60: 148–156.
Copyright (c) 2025 Dieter Korn

This work is licensed under a Creative Commons Attribution 4.0 International License.
Creative Commons Copyright Notices
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License (CC BY 4.0) that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are NOT PERMITTED to post their submitted work online (e.g., in institutional repositories or on personal websites) prior to publication, as it may lead to nomenclatural issues.
