In utero foetal remains of the Cretaceous ichthyosaurian Platypterygius: ontogenetic implications for character state efficacy

  title={In utero foetal remains of the Cretaceous ichthyosaurian Platypterygius: ontogenetic implications for character state efficacy},
  author={Benjamin P. Kear and Maria Zammit},
  journal={Geological Magazine},
  pages={71 - 86}
Abstract Ichthyosaurians provide some of the most famous examples of ‘live birth’ in the amniote fossil record based on spectacular complete skeletons of gravid females. Such remains facilitate direct comparisons between adult and foetal life stages, and thus have significant impact on phylogenetic hypotheses that require discrete character states to be ontogenetically uncoupled. This is especially true for Cretaceous ichthyosaurian taxa, the majority of which have been established using single… 

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The first known neonate Ichthyosaurus communis skeleton: a rediscovered specimen from the Lower Jurassic, UK

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The first known neonate Ichthyosaurus communis skeleton

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The effect of body size on skeletal articulation and completeness in Jurassic Ichthyopterygia (Reptilia)

The study has important implications for the preservation of different body size ranges, in particular, those representing ontogenetic stages in ichthyopterygians and other marine reptile groups, but, more generally, for vertebrates entering the fossil record.

Catutosaurus gaspariniae, gen. et sp. nov. (Ichthyosauria, Thunnosauria) of the Upper Jurassic of Patagonia and the Evolution of the Ophthalmosaurids

ABSTRACT Thunnosaurian ichthyosaurs were one of the most successful lineages of Mesozoic tetrapods in terms of adaptation to a pelagic lifestyle. Among them, the ophthalmosaurids are of particular

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The Slottsmøya Member Lagerstätte ichthyosaurs are significant in that they represent a diverse assemblage of ophthalmosaurids that existed immediately preceding and across the Jurassic–Cretaceous boundary, and expand the known range in size variation of pelvic girdle elements in the clade.

Osteology and phylogeny of Late Jurassic ichthyosaurs from the Slottsmøya Member Lagerstätte (Spitsbergen, Svalbard)

The species was recently synonymized with the Russian Undorosaurus gorodischensis, but it is concluded that there are too many differences, for example in the shape of the stapedial head and the proximal head of the humerus; and too little overlap between specimens, to warrant synonymy on species level.



Postcranial Anatomy of Platypterygius americanus (Reptilia: Ichthyosauria) from the Cretaceous of Wyoming

Comparative assessment suggests that Platypterygius americanus is a valid taxon, and that it is possible to differentiate the various Platyperygius spp.

Cranial morphology of Platypterygius longmani Wade, 1990 (Reptilia : Ichthyosauria) from the Lower Cretaceous of Australia.

Preparation of specimens using acetic acid and application of high-resolution X-ray computed tomographic analyses has revealed many previously unrecorded anatomical details, including the absence of a coronoid and squamosal, and the presence of well-developed epipterygoids facets on the pterygoid and parietal.

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New Metrics To Differentiate Species of Stenopterygius (Reptilia: Ichthyosauria) from the Lower Jurassic of Southwestern Germany

Bivariate and multivariate analyses are used to classify both articulated and disarticulated skeletons to the level of species, using measurement data from individual cranial and postcranial elements.

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Two recently collected specimens of medium- to large-bodied ichthyosaurs from the Slottsmoya Member of the Agardhfjellet, Svalbard, Norway represent two new taxa of ophthalmosaurids.

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Postcranial remains referred to the upper Albian species Platypterygius australis are described, including the first record of pelvic and hind limb elements for this taxon, among the most complete in the world.

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Unusual gut contents in a Cretaceous ichthyosaur

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