Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous
This paper redescribes the holotype skull of the aristonectine elasmosaur Morturneria seymourensis from the upper Maastrichtian of Seymour Island, Antarctica. This description supports the validity of the genus Morturneria, distinct from the genus Aristonectes from Chile and Argentina. The paroccipi...
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Online Access: | https://doi.org/10.1080/02724634.2017.1347570 https://repositorio.uchile.cl/handle/2250/148754 |
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ftunivchile:oai:repositorio.uchile.cl:2250/148754 2023-05-15T13:41:31+02:00 Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous O'Keefe, F. Robin Otero, Rodrigo A. Soto Acuña, Sergio O'Gorman, Jose P. Godfrey, Stephen J. Chatterjee, Sankar 2017 application/pdf https://doi.org/10.1080/02724634.2017.1347570 https://repositorio.uchile.cl/handle/2250/148754 en eng Taylor & Francis Journal of Vertebrate Paleontology, 37:4, e1347570 doi:10.1080/02724634.2017.1347570 https://repositorio.uchile.cl/handle/2250/148754 Attribution-NonCommercial-NoDerivs 3.0 Chile http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ CC-BY-NC-ND Journal of Vertebrate Paleontology Artículo de revista 2017 ftunivchile https://doi.org/10.1080/02724634.2017.1347570 2023-01-29T00:53:31Z This paper redescribes the holotype skull of the aristonectine elasmosaur Morturneria seymourensis from the upper Maastrichtian of Seymour Island, Antarctica. This description supports the validity of the genus Morturneria, distinct from the genus Aristonectes from Chile and Argentina. The paroccipital process of Morturneria is plesiomorphic, similar to Alexandronectes and unlike the autapomorphic occiput of Aristonectes. The palate of Morturneria is autapomorphic in possessing a strongly developed midline keel. The cranium of Morturneria is about 60% complete and preserves the anterior skull roof and palate; both regions were previously unknown in any aristonectine. The combination of the Morturneria holotype and recent research on other aristonectines allows the first confident cranial reconstruction of an aristonectine elasmosaur. The cranial anatomy of both Morturneria and its close relatives is derived relative to all other plesiosaurs, possessing a novel suite of dental and oral cavity adaptions. The suspensorium extends far behind the occipital condyle, and the jaw is long and hoop-like; together these features allowed a large gape and oral cavity volume. The palate of Morturneria is strongly keeled, forming arched lateral oral chambers that further increased oral cavity volume. The dentition of Morturneria is similar to that of Aristonectes, and all share autapomorphic interlocking combs of needle-like teeth that occluded outside the mouth and did not meet tip to tip. The upper and lower dentition formed an oral battery that may have functioned like a sieve in straining food particles from substrate ejected from the oral cavity. We theorize that this highly derived suite of adaptations is convergent with extant gray whales and archaic mysticetes and hypothesize that it functioned similarly in sieve feeding following suction. This is the first identification of whale-like filter feeding in any marine reptile, a condition once claimed to be anatomically impossible. John Deever Drinko Distinguished ... Article in Journal/Newspaper Antarc* Antarctica Seymour Island Universidad de Chile: Repositorio académico Austral Argentina Seymour ENVELOPE(-56.767,-56.767,-64.283,-64.283) Seymour Island ENVELOPE(-56.750,-56.750,-64.283,-64.283) Combs ENVELOPE(-79.150,-79.150,-73.483,-73.483) Journal of Vertebrate Paleontology 37 4 e1347570 |
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Open Polar |
collection |
Universidad de Chile: Repositorio académico |
op_collection_id |
ftunivchile |
language |
English |
description |
This paper redescribes the holotype skull of the aristonectine elasmosaur Morturneria seymourensis from the upper Maastrichtian of Seymour Island, Antarctica. This description supports the validity of the genus Morturneria, distinct from the genus Aristonectes from Chile and Argentina. The paroccipital process of Morturneria is plesiomorphic, similar to Alexandronectes and unlike the autapomorphic occiput of Aristonectes. The palate of Morturneria is autapomorphic in possessing a strongly developed midline keel. The cranium of Morturneria is about 60% complete and preserves the anterior skull roof and palate; both regions were previously unknown in any aristonectine. The combination of the Morturneria holotype and recent research on other aristonectines allows the first confident cranial reconstruction of an aristonectine elasmosaur. The cranial anatomy of both Morturneria and its close relatives is derived relative to all other plesiosaurs, possessing a novel suite of dental and oral cavity adaptions. The suspensorium extends far behind the occipital condyle, and the jaw is long and hoop-like; together these features allowed a large gape and oral cavity volume. The palate of Morturneria is strongly keeled, forming arched lateral oral chambers that further increased oral cavity volume. The dentition of Morturneria is similar to that of Aristonectes, and all share autapomorphic interlocking combs of needle-like teeth that occluded outside the mouth and did not meet tip to tip. The upper and lower dentition formed an oral battery that may have functioned like a sieve in straining food particles from substrate ejected from the oral cavity. We theorize that this highly derived suite of adaptations is convergent with extant gray whales and archaic mysticetes and hypothesize that it functioned similarly in sieve feeding following suction. This is the first identification of whale-like filter feeding in any marine reptile, a condition once claimed to be anatomically impossible. John Deever Drinko Distinguished ... |
format |
Article in Journal/Newspaper |
author |
O'Keefe, F. Robin Otero, Rodrigo A. Soto Acuña, Sergio O'Gorman, Jose P. Godfrey, Stephen J. Chatterjee, Sankar |
spellingShingle |
O'Keefe, F. Robin Otero, Rodrigo A. Soto Acuña, Sergio O'Gorman, Jose P. Godfrey, Stephen J. Chatterjee, Sankar Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous |
author_facet |
O'Keefe, F. Robin Otero, Rodrigo A. Soto Acuña, Sergio O'Gorman, Jose P. Godfrey, Stephen J. Chatterjee, Sankar |
author_sort |
O'Keefe, F. Robin |
title |
Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous |
title_short |
Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous |
title_full |
Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous |
title_fullStr |
Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous |
title_full_unstemmed |
Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous |
title_sort |
cranial anatomy of morturneria seymourensis from antarctica, and the evolution of filter feeding in plesiosaurs of the austral late cretaceous |
publisher |
Taylor & Francis |
publishDate |
2017 |
url |
https://doi.org/10.1080/02724634.2017.1347570 https://repositorio.uchile.cl/handle/2250/148754 |
long_lat |
ENVELOPE(-56.767,-56.767,-64.283,-64.283) ENVELOPE(-56.750,-56.750,-64.283,-64.283) ENVELOPE(-79.150,-79.150,-73.483,-73.483) |
geographic |
Austral Argentina Seymour Seymour Island Combs |
geographic_facet |
Austral Argentina Seymour Seymour Island Combs |
genre |
Antarc* Antarctica Seymour Island |
genre_facet |
Antarc* Antarctica Seymour Island |
op_source |
Journal of Vertebrate Paleontology |
op_relation |
Journal of Vertebrate Paleontology, 37:4, e1347570 doi:10.1080/02724634.2017.1347570 https://repositorio.uchile.cl/handle/2250/148754 |
op_rights |
Attribution-NonCommercial-NoDerivs 3.0 Chile http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ |
op_rightsnorm |
CC-BY-NC-ND |
op_doi |
https://doi.org/10.1080/02724634.2017.1347570 |
container_title |
Journal of Vertebrate Paleontology |
container_volume |
37 |
container_issue |
4 |
container_start_page |
e1347570 |
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1766151727138996224 |