The dorsal shell wall structure of Mesozoic ammonoids [PDF]
Acta Palaeontologica Polonica, 2017 The study of pristine preserved shells of Mesozoic Ammonoidea shows different types of construction and formation of the dorsal shell wall. We observe three major types: (i) The vast majority of Ammonoidea, usually planispirally coiled, has a prismatic ...
Gregor Radtke, Helmut Keupp
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Conellae, enigmatic structures on cephalopod shells—shapes, distribution, and formation [PDF]
Acta Palaeontologica Polonica, 2019 Conellae, enigmatic cone-shaped structures which can be found on the surface of internal moulds of cephalopod shells (predominantly of ammonoids), are regarded herein as the product of remote (biologically induced) biomineralization formed in closed-off ...
René Hoffmann +2 more
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Evolutionary development of the cephalopod arm armature: a review [PDF]
Swiss Journal of Palaeontology, 2021 The cephalopod arm armature is certainly one of the most important morphological innovations responsible for the evolutionary success of the Cephalopoda.
Dirk Fuchs +2 more
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Cephalopod palaeobiology: evolution and life history of the most intelligent invertebrates [PDF]
Swiss Journal of Palaeontology, 2022 Sigurd von Boletzky was a cephalopod researcher who was world-renowned for his enthusiasm for his field of research, for his friendly and calm personality, and, of course, his publications.
Christian Klug +6 more
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Another lesson from beautiful monsters: the case of 'sex reversals' in the Ammonoidea and their significance [PDF]
BMC Ecology and Evolution, 2021 Background Expression of sexual dimorphism is recognised in various fossil groups of molluscs such as the Ammonoidea, an extinct group of shelled cephalopods.
Camille Frau, Pierre-Yves Boursicot
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Failed prey or peculiar necrolysis? Isolated ammonite soft body from the Late Jurassic of Eichstätt (Germany) with complete digestive tract and male reproductive organs [PDF]
Swiss Journal of Palaeontology, 2021 Ammonoid soft parts have been rarely described. Here, we document the soft parts of a perisphinctid ammonite from the early Tithonian of Wintershof near Eichstätt (Germany). This exceptional preservation was enabled by the special depositional conditions
Christian Klug +3 more
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The balancing act of Nipponites mirabilis (Nostoceratidae, Ammonoidea): Managing hydrostatics throughout a complex ontogeny. [PDF]
PLoS ONE, 2020 Nipponites is a heteromorph ammonoid with a complex and unique morphology that obscures its mode of life and ethology. The seemingly aberrant shell of this Late Cretaceous nostoceratid seems deleterious. However, hydrostatic simulations suggest that this
David J Peterman +2 more
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First record of non-mineralized cephalopod jaws and arm hooks from the latest Cretaceous of Eurytania, Greece [PDF]
Swiss Journal of Palaeontology, 2020 Due to the lower fossilization potential of chitin, non-mineralized cephalopod jaws and arm hooks are much more rarely preserved as fossils than the calcitic lower jaws of ammonites or the calcitized jaw apparatuses of nautilids. Here, we report such non-
Christian Klug +3 more
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Ontogeny of highly variable ceratitid ammonoids from the Anisian (Middle Triassic) [PDF]
PeerJ, 2021 Ammonoids reached their greatest diversity during the Triassic period. In the early Middle Triassic (Anisian) stage, ammonoid diversity was dominated by representatives of the family Ceratitidae.
Eva Alexandra Bischof +3 more
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The old and the new plankton: ecological replacement of associations of mollusc plankton and giant filter feeders after the Cretaceous? [PDF]
PeerJ, 2018 Owing to their great diversity and abundance, ammonites and belemnites represented key elements in Mesozoic food webs. Because of their extreme ontogenetic size increase by up to three orders of magnitude, their position in the food webs likely changed ...
Amane Tajika +2 more
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