Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica
Temnospondyl amphibians are common in non-marine Triassic assemblages, including in the Fremouw Formation (Lower to Middle Triassic) of Antarctica. Temnospondyls were among the first tetrapods to be collected from Antarctica, but their record from the lower Fremouw Formation has long been tenuous. O...
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2022
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ftbioone:10.1017/jpa.2021.115 2024-06-02T07:58:38+00:00 Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica Bryan M. Gee Peter J. Makovicky Christian A. Sidor Bryan M. Gee Peter J. Makovicky Christian A. Sidor world 2022-06-06 text/HTML https://doi.org/10.1017/jpa.2021.115 en eng The Paleontological Society doi:10.1017/jpa.2021.115 All rights reserved. https://doi.org/10.1017/jpa.2021.115 Text 2022 ftbioone https://doi.org/10.1017/jpa.2021.115 2024-05-07T00:48:07Z Temnospondyl amphibians are common in non-marine Triassic assemblages, including in the Fremouw Formation (Lower to Middle Triassic) of Antarctica. Temnospondyls were among the first tetrapods to be collected from Antarctica, but their record from the lower Fremouw Formation has long been tenuous. One taxon, ‘Austrobrachyops jenseni,’ is represented by a type specimen comprising only a partial pterygoid, which is now thought to belong to a dicynodont. A second taxon, ‘Cryobatrachus kitchingi,’ is represented by a type specimen comprising a nearly complete skull, but the specimen is only exposed ventrally, and uncertainty over its ontogenetic maturity and some aspects of its anatomy has led it to be designated as a nomen dubium by previous workers. Here, we redescribe the holotype of ‘C. kitchingi,’ an undertaking that is augmented by tomographic analysis. Most of the original interpretations and reconstructions cannot be substantiated, and some are clearly erroneous. Although originally classified as a lydekkerinid, the purported lydekkerinid characteristics are shown to be unfounded or no longer diagnostic for the family. We instead identify numerous features shared with highly immature capitosaurs, a large-bodied clade documented in the upper Fremouw Formation of Antarctica and elsewhere in the Lower Triassic. Additionally, we describe a newly collected partial skull from the lower Fremouw Formation that represents a relatively mature, small-bodied individual, which we provisionally refer to Lydekkerinidae; this specimen represents the most confident identification of a lydekkerinid from Antarctica to date. Text Antarc* Antarctica BioOne Online Journals Journal of Paleontology 96 3 658 683 |
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English |
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Temnospondyl amphibians are common in non-marine Triassic assemblages, including in the Fremouw Formation (Lower to Middle Triassic) of Antarctica. Temnospondyls were among the first tetrapods to be collected from Antarctica, but their record from the lower Fremouw Formation has long been tenuous. One taxon, ‘Austrobrachyops jenseni,’ is represented by a type specimen comprising only a partial pterygoid, which is now thought to belong to a dicynodont. A second taxon, ‘Cryobatrachus kitchingi,’ is represented by a type specimen comprising a nearly complete skull, but the specimen is only exposed ventrally, and uncertainty over its ontogenetic maturity and some aspects of its anatomy has led it to be designated as a nomen dubium by previous workers. Here, we redescribe the holotype of ‘C. kitchingi,’ an undertaking that is augmented by tomographic analysis. Most of the original interpretations and reconstructions cannot be substantiated, and some are clearly erroneous. Although originally classified as a lydekkerinid, the purported lydekkerinid characteristics are shown to be unfounded or no longer diagnostic for the family. We instead identify numerous features shared with highly immature capitosaurs, a large-bodied clade documented in the upper Fremouw Formation of Antarctica and elsewhere in the Lower Triassic. Additionally, we describe a newly collected partial skull from the lower Fremouw Formation that represents a relatively mature, small-bodied individual, which we provisionally refer to Lydekkerinidae; this specimen represents the most confident identification of a lydekkerinid from Antarctica to date. |
author2 |
Bryan M. Gee Peter J. Makovicky Christian A. Sidor |
format |
Text |
author |
Bryan M. Gee Peter J. Makovicky Christian A. Sidor |
spellingShingle |
Bryan M. Gee Peter J. Makovicky Christian A. Sidor Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica |
author_facet |
Bryan M. Gee Peter J. Makovicky Christian A. Sidor |
author_sort |
Bryan M. Gee |
title |
Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica |
title_short |
Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica |
title_full |
Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica |
title_fullStr |
Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica |
title_full_unstemmed |
Upside down: ‘Cryobatrachus’ and the lydekkerinid record from Antarctica |
title_sort |
upside down: ‘cryobatrachus’ and the lydekkerinid record from antarctica |
publisher |
The Paleontological Society |
publishDate |
2022 |
url |
https://doi.org/10.1017/jpa.2021.115 |
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world |
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Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
https://doi.org/10.1017/jpa.2021.115 |
op_relation |
doi:10.1017/jpa.2021.115 |
op_rights |
All rights reserved. |
op_doi |
https://doi.org/10.1017/jpa.2021.115 |
container_title |
Journal of Paleontology |
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96 |
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3 |
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658 |
op_container_end_page |
683 |
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1800742050246688768 |