A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology
Placoderms are an extinct group of early jawed vertebrates that play a key role in understanding the evolution of the gnathostome body plan, including the origin of novelties such as jaws, teeth, and pelvic fins. As placoderms have a poorly ossified axial skeleton, preservation of the mainly cartila...
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Frontiers Media S.A.
2022-10-01
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| Series: | Frontiers in Ecology and Evolution |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fevo.2022.969158/full |
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| author | Melina Jobbins Martin Rücklin Martin Rücklin Humberto G. Ferrón Humberto G. Ferrón Christian Klug |
| author_facet | Melina Jobbins Martin Rücklin Martin Rücklin Humberto G. Ferrón Humberto G. Ferrón Christian Klug |
| author_sort | Melina Jobbins |
| collection | DOAJ |
| description | Placoderms are an extinct group of early jawed vertebrates that play a key role in understanding the evolution of the gnathostome body plan, including the origin of novelties such as jaws, teeth, and pelvic fins. As placoderms have a poorly ossified axial skeleton, preservation of the mainly cartilaginous axial and fin elements is extremely rare, contrary to the heavily mineralized bones of the skull and thoracic armor. Therefore, the gross anatomy of the animals and body shape is only known from a few taxa, and reconstructions of the swimming function and ecology are speculative. Here, we describe articulated specimens preserving skull roofs, shoulder girdles, most fins, and body outlines of a newly derived arthrodire. Specimens of the selenosteid Amazichthys trinajsticae gen. et sp. nov. display a skull roof with reticular ornamentation and raised sensory lines like Driscollaspis, a median dorsal plate with a unique sharp posterior depression, the pelvic girdle, the proportions and shape of the pectoral, dorsal, and caudal fins as well as a laterally enlarged region resembling the lateral keel of a few modern sharks and bony fishes. Our new phylogenetic analyses support the monophyly of the selenosteid family and place the new genus in a clade with Melanosteus, Enseosteus, Walterosteus, and Draconichthys. The shape of its body and heterocercal caudal fin in combination with the pronounced “lateral keel” suggest Amazichthys trinajsticae was an active macropelagic swimmer capable of reaching high swimming speeds. |
| first_indexed | 2024-04-12T16:13:33Z |
| format | Article |
| id | doaj.art-458cc9c3e691453993c12fd68cbbbbea |
| institution | Directory Open Access Journal |
| issn | 2296-701X |
| language | English |
| last_indexed | 2024-04-12T16:13:33Z |
| publishDate | 2022-10-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Ecology and Evolution |
| spelling | doaj.art-458cc9c3e691453993c12fd68cbbbbea2022-12-22T03:25:48ZengFrontiers Media S.A.Frontiers in Ecology and Evolution2296-701X2022-10-011010.3389/fevo.2022.969158969158A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphologyMelina Jobbins0Martin Rücklin1Martin Rücklin2Humberto G. Ferrón3Humberto G. Ferrón4Christian Klug5Palaeontological Institute and Museum, University of Zurich, Zürich, SwitzerlandNaturalis Biodiversity Center, Leiden, NetherlandsSylvius Laboratory, Institute of Biology, University of Leiden, Leiden, NetherlandsInstituto Cavanilles de Biodiversidad y Biología Evolutiva, Paterna, SpainSchool of Earth Sciences, University of Bristol, Bristol, United KingdomPalaeontological Institute and Museum, University of Zurich, Zürich, SwitzerlandPlacoderms are an extinct group of early jawed vertebrates that play a key role in understanding the evolution of the gnathostome body plan, including the origin of novelties such as jaws, teeth, and pelvic fins. As placoderms have a poorly ossified axial skeleton, preservation of the mainly cartilaginous axial and fin elements is extremely rare, contrary to the heavily mineralized bones of the skull and thoracic armor. Therefore, the gross anatomy of the animals and body shape is only known from a few taxa, and reconstructions of the swimming function and ecology are speculative. Here, we describe articulated specimens preserving skull roofs, shoulder girdles, most fins, and body outlines of a newly derived arthrodire. Specimens of the selenosteid Amazichthys trinajsticae gen. et sp. nov. display a skull roof with reticular ornamentation and raised sensory lines like Driscollaspis, a median dorsal plate with a unique sharp posterior depression, the pelvic girdle, the proportions and shape of the pectoral, dorsal, and caudal fins as well as a laterally enlarged region resembling the lateral keel of a few modern sharks and bony fishes. Our new phylogenetic analyses support the monophyly of the selenosteid family and place the new genus in a clade with Melanosteus, Enseosteus, Walterosteus, and Draconichthys. The shape of its body and heterocercal caudal fin in combination with the pronounced “lateral keel” suggest Amazichthys trinajsticae was an active macropelagic swimmer capable of reaching high swimming speeds.https://www.frontiersin.org/articles/10.3389/fevo.2022.969158/fullSelenosteidaebody outlineMoroccoFamenniangeometric morphometrics |
| spellingShingle | Melina Jobbins Martin Rücklin Martin Rücklin Humberto G. Ferrón Humberto G. Ferrón Christian Klug A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology Frontiers in Ecology and Evolution Selenosteidae body outline Morocco Famennian geometric morphometrics |
| title | A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology |
| title_full | A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology |
| title_fullStr | A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology |
| title_full_unstemmed | A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology |
| title_short | A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology |
| title_sort | new selenosteid placoderm from the late devonian of the eastern anti atlas morocco with preserved body outline and its ecomorphology |
| topic | Selenosteidae body outline Morocco Famennian geometric morphometrics |
| url | https://www.frontiersin.org/articles/10.3389/fevo.2022.969158/full |
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