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Zurich Open Repository and Archive University of Zurich Main Library Strickhofstrasse 39 CH-8057 Zurich www.zora.uzh.ch Year: 2017 Origin of the Konservatlagerstätten of the southern Maïder (Morocco) and gnathostome preservation Klug, Christian ; Frey, Linda ; Pohle, Alexander ; Rücklin, Martin Abstract: In the Famennian of the eastern Anti-Atlas, microremains of gnathostomes are quite com- mon in some strata due to condensed sedimentation, particularly in the Tafilalt. In the latter region, chondrichthyan diversity can be reasonably high (up to nine species in one layer). By contrast, in the Famennian of the southern Maïder Basin, chondrichthyan diversity appears to be lower (four to five species) and genera such as Clairina, Jalodus and Protacrodus have not been found yet although they are documented from the neighboring Tafilalt Basin (Ginter et al. 2002; Derycke et al. 2008). We address the questions for the ecological factors controlling these differences in diversity and fossil preservation. The latter question is of interest because only in the Maïder Basin, chondrichthyans have been discovered preserving cartilaginous body parts as well as soft tissues. Preservation has been examined by analyzing the mineral composition of various Famennian fossils from the Maïder and the Tafilalt using XRD (X-ray Diffraction) at the Swiss Federal Institute of Technology in Zurich (ETHZ). The results show thatindeed the chondrichthyan musculature is now preserved in hematite and other ferric minerals. Both placoderm bones and chondrichthyan cartilage are preserved in hydroxylapatite, fluorapatite or francolite (phos- phates). Particularly the abundance of ferric oxides and hydroxides points at pyrite, which was altered due to deep weathering in the desert environment. This is corroborated by rare finds of pyritized fossils from the same strata in depths of over 10 m below today’s surface. In turn, this primary abundance of pyrite (now ferric oxides and hydroxides) in combination with the clayey facies and the scarcity of ben- thos in some strata suggests that the sediments containing exceptionally preserved gnathostomes were deposited under oxygenpoor conditions (Klug et al. 2016). This is supported by the palaeogeographical situation of the Maïder Basin that was closed to the south, west and north by land, while to the east, the shallower regions of the Tafilalt Pelagic Ridge limited water exchange (Wendt 1988; Kaufmann 1998). Hypoxic to anoxic conditions ultimately explain the absence of the protacrodontids, which mainly occur in shallower, better oxygenated waters (Ginter 2000). Clairina and Jalodus on the other hand likely pre- ferred deeper environments than the one in the Maïder Basin. Following Ginter (2000), the taxa present in the Maïder (Phoebodus and cladodonts) point at an intermediate water depth. Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-138408 Conference or Workshop Item Published Version Originally published at: Klug, Christian; Frey, Linda; Pohle, Alexander; Rücklin, Martin (2017). Origin of the Konservatlagerstät- ten of the southern Maïder (Morocco) and gnathostome preservation. In: 14th International Symposium on Early and Lower Vertebrates, Chęciny, Poland, 3 July 2017 - 7 July 2017, 52. July 2017 Ichthyolith Issues Special Publication 13 14 th International Symposium on Early and Lower Vertebrates Ch ęciny, Poland, 3-8.07.2017 Honoring Susan Turner Conference Abstracts and Field-trip Guidebook ISSN 1302-1314 Edited by Michał Ginter Special Publication 13 of Ichthyolith Issues ISSN 1302-1314 Published by University of Warsaw © Copyright 2017 Cover: Tooth of a phoebodontid shark Thrinacodus ferox (from Turner 1982), and a tetrapod from Zachełmie with its trackway (from Nied źwiedzki et al. 2010) Title page drawing: Antarctilamniform shark Wellerodus Turner, 1997, by Bogusław Waksmundzki (from Zapalski et al. 2017) Conference logo: Castle at Ch ęciny and early vertebrates Copies and pdf available from Michał Ginter Faculty of Geology, University of Warsaw Żwirki i Wigury 93, 02-089 Warsaw Poland E-mail: [email protected] 2 14 th International Symposium on Early and Lower Vertebrates Ch ęciny, Poland, 3-8.07.2017 Organised by Instytut Geologii Podstawowej, Wydział Geologii, Uniwersytet Warszawski (Institute of Geology, Faculty of Geology, Warsaw University) Pa ństwowy Instytut Geologiczny – Pa ństwowy Instytut Badawczy (Polish Geological Institute – National Research Institute) and Stowarzyszenie Delta (Delta Association) Organising Committee Michał Ginter and Piotr Szrek Patrycja Dworczak, Roksana Skrzycka, Piotr Skrzycki, Olga Wilk General schedule 3.07. : Registration in Warsaw, evening ice-breaking party 4.07. : Travel to Ch ęciny. Zachełmie Quarry. Opening session. 5.07. : Sessions. Sightseeing at Ch ęciny. 6.07. : Sessions. Wietrznia Quarry. Conference dinner. 7.07. : Field trips, Ujazd and Płucki. Evening grill. 8.07. : Return to Warsaw. 3 Contents 1. Introduction HANS -PETER SCHULTZE Fifty years of symposia on Early/Lower Vertebrates . 9 ALAIN BLIECK & CAROLE BURROW Fifty years of international symposia on early/lower vertebrates : honoring Dr. Susan Turner, colleague, friend and mentor . 10 VACHIK HAIRAPETIAN Early/Lower Vertebrates Meetings: Sue Turner and her impact on palaeoichthyology in the Middle East . 12 WAYNE ITANO Some brief remarks on Susan Turner and my experiences with the Early/Lower Vertebrates Meetings . 12 MICHAŁ GINTER International Symposium on Early and Lower Vertebrates in the Holy Cross Mountains, Poland . 13 Major works by Sue Turner . 15 2. Abstracts of conference presentations ALAIN BLIECK Tesseraspidiformes (Vertebrata: †Pteraspidomorphi: Heterostraci), a group of enigmatic early vertebrates . 21 HÉCTOR BOTELLA SEVILLA , FERNANDO ANTONIO MARTÍN ARNAL , BORJA ESTEVE -ALTAVA , VINCENT DUPRET Anatomical Networks Analysis of the skull roof of placoderms . 22 OSKAR BREMER , GRZEGORZ NIED ŹWIEDZKI , HENNING BLOM , MAREK DEC & WOJCIECH KOZŁOWSKI The first vertebrate microremains from the upper Silurian of the Holy Cross Mountains, Poland . 24 CAROLE BURROW , MICHAEL NEWMAN , JAN DEN BLAAUWEN , ROGER JONES & ROBERT DAVIDSON The Early Devonian ischnacanthiform acanthodian Ischnacanthus gracilis from the Midland Valley of Scotland . 25 CAROLE BURROW & PIOTR SZREK Acanthodians from the Lower Devonian (Emsian) 'Placoderm Sandstone', Holy Cross Mountains, Poland . 25 ROBERT K. CARR The Cleveland Shale fauna and the Devonian–Mississippian transition in Ohio and Pennsylvania (U.S.A.) . 26 MARCO CASTIELLO , CHARLINE PINNA , ALEXANDER O. IVANOV & MARTIN D. BRAZEAU Redescription of Kolymaspis sibirica Bystrow 1956 and the affinities of acanthothoracid placoderms . 28 DONGLEI CHEN , HENNING BLOM , SOPHIE SANCHEZ , PAUL TAFFOREAU & PER E. AHLBERG 3D microstructures of the earliest osteichthyan teeth and life history of the stem osteichthyans Andreolepis and Lophosteus . 29 BRIAN CHOO , BENEDICT KING , JOHN LONG & GAVIN YOUNG New material of an unusual tetrapodomorph fish from the Middle Devonian of central Australia . 30 4 ALICE CLEMENT , BEN KING , KATE TRINAJSTIC , RICHARD CLOUTIER & JOHN LONG An exceptional 3D coelacanth (Osteichthyes: Sarcopterygii) from the Devonian of Australia and interpretation of fossil cranial endocasts . 31 AIDAN COUZENS & MARTIN RÜCKLIN Examining the evolution and developmental mechanisms of oral odontode complexity in basal crown-group gnathostomes . 32 RICHARD PETER DEARDEN , MATT FRIEDMAN , PAUL TAFFOREAU , ROBERT ATWOOD & MARTIN D. BRAZEAU Articulated branchial skeletons in the “acanthodian” stem-chondrichthyans Ptomacanthus anglicus and Diplacanthus crassissimus . 33 HUMBERTO G. FERRÓN , JOSE F. PALACIOS -ABELLA, CARLOS MARTÍNEZ -PÉREZ & HÉCTOR BOTELLA Predicting ectoparasitic pressure and grouping behavior in extinct early vertebrates from the study of their squamations . 34 HUMBERTO G. FERRÓN , SUSAN TURNER , BORJA CASCALES -MIÑANA , CARLOS MARTÍNEZ -PÉREZ & HÉCTOR BOTELLA Ecological diversification patterns and diversity changes of thelodonts . 35 LINDA FREY , MICHAEL COATES , MICHAŁ GINTER & CHRISTIAN KLUG Skeletal remains of Phoebodus politus Newberry 1889 (Chondrichthyes:Elasmobranchii) from a Famennian Konservatlagerstätte in the eastern Anti-Atlas (Morocco) and its ecology . 36 ROBERT W. GESS Estuarine fish breeding grounds: a comparison of the Famennian aged Waterloo Farm lagerstätten and contemporary systems . 37 SAM GILES & THODORIS ARGYRIOU Reassessment of Perleidus stoschiensis from the Early Triassic of Greenland MICHAŁ GINTER Symmoriiform sharks from the Pennsylvanian of Nebraska . 39 VADIM GLINSKIY Evolutionary lineages in the family Psammosteidae (Agnatha: Pteraspidiformes). 39 MICHAEL D. GOTTFRIED & R. 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  • Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha)

    Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha)

    Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha) by Richard Kissel A thesis submitted in conformity with the requirements for the degree of doctor of philosophy Graduate Department of Ecology & Evolutionary Biology University of Toronto © Copyright by Richard Kissel 2010 Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha) Richard Kissel Doctor of Philosophy Graduate Department of Ecology & Evolutionary Biology University of Toronto 2010 Abstract Based on dental, cranial, and postcranial anatomy, members of the Permo-Carboniferous clade Diadectidae are generally regarded as the earliest tetrapods capable of processing high-fiber plant material; presented here is a review of diadectid morphology, phylogeny, taxonomy, and paleozoogeography. Phylogenetic analyses support the monophyly of Diadectidae within Diadectomorpha, the sister-group to Amniota, with Limnoscelis as the sister-taxon to Tseajaia + Diadectidae. Analysis of diadectid interrelationships of all known taxa for which adequate specimens and information are known—the first of its kind conducted—positions Ambedus pusillus as the sister-taxon to all other forms, with Diadectes sanmiguelensis, Orobates pabsti, Desmatodon hesperis, Diadectes absitus, and (Diadectes sideropelicus + Diadectes tenuitectes + Diasparactus zenos) representing progressively more derived taxa in a series of nested clades. In light of these results, it is recommended herein that the species Diadectes sanmiguelensis be referred to the new genus
  • 'Placoderm' (Arthrodira)

    'Placoderm' (Arthrodira)

    Jobbins et al. Swiss J Palaeontol (2021) 140:2 https://doi.org/10.1186/s13358-020-00212-w Swiss Journal of Palaeontology RESEARCH ARTICLE Open Access A large Middle Devonian eubrachythoracid ‘placoderm’ (Arthrodira) jaw from northern Gondwana Melina Jobbins1* , Martin Rücklin2, Thodoris Argyriou3 and Christian Klug1 Abstract For the understanding of the evolution of jawed vertebrates and jaws and teeth, ‘placoderms’ are crucial as they exhibit an impressive morphological disparity associated with the early stages of this process. The Devonian of Morocco is famous for its rich occurrences of arthrodire ‘placoderms’. While Late Devonian strata are rich in arthrodire remains, they are less common in older strata. Here, we describe a large tooth-bearing jaw element of Leptodontich- thys ziregensis gen. et sp. nov., an eubrachythoracid arthrodire from the Middle Devonian of Morocco. This species is based on a large posterior superognathal with a strong dentition. The jawbone displays features considered syna- pomorphies of Late Devonian eubrachythoracid arthrodires, with one posterior and one lateral row of conical teeth oriented postero-lingually. μCT-images reveal internal structures including pulp cavities and dentinous tissues. The posterior orientation of the teeth and the traces of a putative occlusal contact on the lingual side of the bone imply that these teeth were hardly used for feeding. Similar to Compagopiscis and Plourdosteus, functional teeth were pos- sibly present during an earlier developmental stage and have been worn entirely. The morphological features of the jaw element suggest a close relationship with plourdosteids. Its size implies that the animal was rather large. Keywords: Arthrodira, Dentition, Food web, Givetian, Maïder basin, Palaeoecology Introduction important to reconstruct character evolution in early ‘Placoderms’ are considered as a paraphyletic grade vertebrates.