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Current Biology
For over 70 million years, during the Paleozoic, the placoderms (Greek for 'plated skin'), an extinct group of armoured fishes, were the most abundant and diverse vertebrates on our planet. Some of the first placoderm fossils discovered - such as Bothriolepis with its bone-covered pectoral fins - seemed so bizarre that they were thought to represent ...
John A, Long, Kate, Trinajstic
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For over 70 million years, during the Paleozoic, the placoderms (Greek for 'plated skin'), an extinct group of armoured fishes, were the most abundant and diverse vertebrates on our planet. Some of the first placoderm fossils discovered - such as Bothriolepis with its bone-covered pectoral fins - seemed so bizarre that they were thought to represent ...
John A, Long, Kate, Trinajstic
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Exceptional preservation of organs in Devonian placoderms from the Gogo lagerstätte
Science, 2022The origin and early diversification of jawed vertebrates involved major changes to skeletal and soft anatomy. Skeletal transformations can be examined directly by studying fossil stem gnathostomes; however, preservation of soft anatomy is rare. We describe the only known example of a three-dimensionally mineralized heart, thick-walled stomach, and ...
Kate Trinajstic +12 more
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Histology of “placoderm” dermal skeletons: Implications for the nature of the ancestral gnathostome [PDF]
Journal of Morphology, 2013 AbstractThe vertebrate dermal skeleton has long been interpreted to have evolved from a primitive condition exemplified by chondrichthyans. However, chondrichthyans and osteichthyans evolved from an ancestral gnathostome stem‐lineage in which the dermal skeleton was more extensively developed.
Sam Giles +2 more
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Further consideration of placoderm evolution
Journal of Vertebrate Paleontology, 1983ABSTRACT The flight performances of Pteranodon ingens and Nyctosaurus gracilis from the Upper Cretaceous of Kansas were modeled using data from a Sailvane hang-glider which has an airfoil similar to that of a pterosaur. The aerodynamics of large pterosaurs were mainly dictated by three parameters: low wing loadings, wings with high aspect ratios, and ...
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XV.—The Paired Fins of Placoderms
Transactions of the Royal Society of Edinburgh, 1947Within the last twenty years our knowledge of the structure and distribution of the armoured Placodermi (including Arthrodira, Ptyctodonta, Phyllolepida, Macropetalichthyida, Rhenanida, and Antiarcha) has increased tremendously. The writer is engaged on a morphogenetic analysis of the group, early publication of which is uncertain.
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Phenotypic plasticity, polymorphism and phylogeny within placoderms
Acta Zoologica, 2009AbstractIntraspecies variation, polymorphism and asymmetric traits are observed within two families of Arthrodira, the Incisoscutidae and Camuropiscidae, from the Gogo Formation in northern Western Australia. Individual plates of the head and trunk shield show considerable variation between individuals.
K. Trinajstic, K. Dennis‐Bryan
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A primitive placoderm sheds light on the origin of the jawed vertebrate face
Nature, 2014Extant vertebrates form two clades, the jawless Cyclostomata (lampreys and hagfishes) and the jawed Gnathostomata (all other vertebrates), with contrasting facial architectures. These arise during development from just a few key differences in the growth patterns of the cranial primordia: notably, the nasal sacs and hypophysis originate from a single ...
Vincent, Dupret +4 more
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Histologic Studies of Ostracoderms, Placoderms and Fossil Elasmobranchs
Zoologica Scripta, 1980An account is given of the structure and growth of certain ptyctodontid tooth plates, especially those of Ctenurella gladbachensis, based on study by light microscopy and the SEM. These tooth plates consist of a framework of acellular bone tissue and an interior hard tissue referred to as pleromin.
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Dynamics of placoderm distribution in the Prague Basin (Czech Republic)
GFF, 2014The occurrence of placoderms in the Prague Basin (Bohemian Massif; Czech Republic) shows a very unsteady distribution in space and time. The most abundant specimens are in the Lochkovian and, through decrease in the Pragian, they become rare towards the Givetian.
Valéria Vaškaninová, Petr Kraft
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The first placoderm fish from the Lower Devonian of Poland
Journal of Vertebrate Paleontology, 2015Fossils remains of placoderms are so characteristic for the Lower Devonian deposits in the Holy Cross Mountains, central Poland (Gurich, 1896), that these rocks are colloquially named the ‘Placoder...
Piotr Szrek +2 more
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