<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Extensive bulk-sampling of the continuous Cretaceous-Paleogene boundary section at Gams (Styria, Austria) allows for the first time the description of the elasmobranch communities inhabiting the bathyal environment of this well-known section. The sampled succession comprises six horizons from the uppermost Maastrichtian (upper part of <italic>Nephrolites frequens</italic> Zone CC26) and five horizons from the lowermost Danian (Zone NP1), which yielded a total of 1852 elasmobranch teeth. Although the majority of the teeth are not well preserved, this study enabled the description of at least 16 taxa of the orders Hexanchiformes, Squaliformes, Orectolobiformes, Lamniformes and Carcharhiniformes, providing a rare snapshot of elasmobranch diversity of this specific environmental setting. Beside minor diversity fluctuations between the assemblages, the extensive bulk-sampling of this section did not reveal a marked diversity decline related to the end-Cretaceous mass extinction event. However, a noteworthy correlation between the deepening upward trend of the section with the appearance of frilled and goblin sharks points to changes in palaeobathymetry, which is also reflected in the increase of the total proportion of squaliform teeth in the uppermost sampled horizon. Furthermore, teeth of the extinct triakid <italic>Palaeogaleus</italic> were recovered exclusively from the Danian deeper deposits, expanding the palaeoecological range of the genus down to fairly deep marine environments. In addition, this study provides the first record of the lamniform <italic>Cretolamna</italic> ex gr. <italic>borealis</italic> from the Danian of the Tethyan Realm expanding the palaeogeographic distribution of this group.</p>
</abstract>

Extensive bulk-sampling of the continuous Cretaceous-Paleogene boundary section at Gams (Styria, Austria) allows for the first time the description of the elasmobranch communities inhabiting the bathyal environment of this well-known section. The sampled succession comprises six horizons from the uppermost Maastrichtian (upper part of Nephrolites frequens Zone CC26) and five horizons from the lowermost Danian (Zone NP1), which yielded a total of 1852 elasmobranch teeth. Although the majority of the teeth are not well preserved, this study enabled the description of at least 16 taxa of the orders Hexanchiformes, Squaliformes, Orectolobiformes, Lamniformes and Carcharhiniformes, providing a rare snapshot of elasmobranch diversity of this specific environmental setting. Beside minor diversity fluctuations between the assemblages, the extensive bulk-sampling of this section did not reveal a marked diversity decline related to the end-Cretaceous mass extinction event. However, a noteworthy correlation between the deepening upward trend of the section with the appearance of frilled and goblin sharks points to changes in palaeobathymetry, which is also reflected in the increase of the total proportion of squaliform teeth in the uppermost sampled horizon. Furthermore, teeth of the extinct triakid Palaeogaleus were recovered exclusively from the Danian deeper deposits, expanding the palaeoecological range of the genus down to fairly deep marine environments. In addition, this study provides the first record of the lamniform Cretolamna ex gr. borealis from the Danian of the Tethyan Realm expanding the palaeogeographic distribution of this group.

Elasmobranch assemblages from a bathyal environment spanning the Cretaceous-Paleogene boundary in Austria

Department of Earth Sciences, NAWI Geocenter

Austrian Journal of Earth Sciences

This work is licensed under the Creative Commons Attribution 4.0 International License.

Extensive bulk-sampling of the continuous Cretaceous-Paleogene boundary section at Gams (Styria, Austria) allows for the first time the description of the...

Elasmobranch assemblages from a bathyal environment spanning the Cretaceous-Paleogene boundary in Austria

Publié en ligne: 03 févr. 2024

Pages: 1 - 11

Reçu: 10 oct. 2023

Accepté: 22 janv. 2024

DOI: https://doi.org/10.17738/ajes.2024.0001

Mots clés
Maastrichtian, Danian, Squaliformes, deep-marine, palaeoecology

© 2024 Iris Feichtinger et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Elasmobranch assemblages from a bathyal environment spanning the Cretaceous-Paleogene boundary in Austria

Publié en ligne: 03 févr. 2024

Pages: 1 - 11

Reçu: 10 oct. 2023

Accepté: 22 janv. 2024

DOI: https://doi.org/10.17738/ajes.2024.0001

Mots clésMaastrichtian, Danian, Squaliformes, deep-marine, palaeoecology

© 2024 Iris Feichtinger et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Mots clés
Maastrichtian, Danian, Squaliformes, deep-marine, palaeoecology