Davletkulia a tapinocephaloid synapsid (not a bolosaurid) + Acheloma cryptatheria, new trematopid temnospondyl species from Permian of Oklahoma
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Ben Creisler
Oct 17, 2024, 2:23:35 PMOct 17
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Ben Creisler
Some recent Permian tetrapod papers:
The holotype (an isolated tooth) of the largest-known member of the family Bolosauridae, Davletkulia gigantea Ivachnenko, 1990, from the middle Permian Yaman-Yushatyr’ locality, Orenburg Region, Russia, is reassigned to the herbivorous dinocephalians of the superfamily Tapinocephaloidea. This attribution is supported by the shape of the tooth crown and patterns of wear and resorption, as well as by the absence of reparative (tertiary) dentine inside the pulp cavity at the late stage of tooth functioning. The morphology of the holotype reveals that D. gigantea is a valid species and the third representative of the group after Ulemosaurus svijagensis and U. gigas, to be described from Eastern Europe. Judging from the Ocher age of the type locality, D. gigantea is the oldest-known tapinocephaloid known from the tetrapod assemblages of the region.
Acheloma cryptatheria sp. nov.
Adrian F. Osterling Arias, Ethan D. Mooney, Joseph J. Bevitt & Robert R. Reisz (2024)
A new trematopid from the lower Permian of Oklahoma and new insights into the genus Acheloma.
PLoS ONE 19(10): e0309393
doi: https://doi.org/10.1371/journal.pone.0309393
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0309393
Modern-day terrestrial amphibians pale in comparison to their monstrous ancient relatives, the Late Carboniferous and Early Permian trematopid temnospondyls. With a skeleton that clearly indicated a terrestrial mode of life and armed with an impressive set of large, recurved marginal dentition and palatal fangs for holding their prey—this group of terrestrial temnospondyls roamed North America and Central Europe as a top predator. Lack of substantial informative fossil material has previously limited our understanding of trematopid diversity and ontogeny. Fortunately, this has improved in the last few decades with the help of exceptional localities like the Early Permian locality Richards Spur. While multiple species of dissorophid temnospondyl have been described from Richards Spur, only one trematopid species has been confidently recognized -Acheloma dunni. Here, we report on the presence of a new large, relatively mature trematopid skull from this famous locality, found encased within a limestone rich block composed mostly of skeletal remains from several other taxa. With the help of neutron computed tomography (nCT), a non-invasive method of analyzing internal and external morphologies, this specimen has revealed several features consistent with the genus, Acheloma, but distinct from Acheloma cumminsi and Acehloma dunni. The identification of these new features, in addition to the characters it shares with other Acheloma species, not only constitute it as a new species of this genus, but also challenges the notion of having synonymized Acheloma dunni with Acheloma cumminsi. In this study, we also unveil new anatomical characters that are potentially independent of ontogeny and could therefore help clarify some of the phylogenetic relationships of this fascinating group of Paleozoic terrestrial predators.
V. V. Bulanov (2024)
On the Taxonomic Affinity of Davletkulia gigantea Ivachnenko
Paleontological Journal 58: 586 - 592
https://doi.org/10.1134/S0031030124600628
https://link.springer.com/article/10.1134/S0031030124600628
On the Taxonomic Affinity of Davletkulia gigantea Ivachnenko
Paleontological Journal 58: 586 - 592
https://doi.org/10.1134/S0031030124600628
https://link.springer.com/article/10.1134/S0031030124600628
The holotype (an isolated tooth) of the largest-known member of the family Bolosauridae, Davletkulia gigantea Ivachnenko, 1990, from the middle Permian Yaman-Yushatyr’ locality, Orenburg Region, Russia, is reassigned to the herbivorous dinocephalians of the superfamily Tapinocephaloidea. This attribution is supported by the shape of the tooth crown and patterns of wear and resorption, as well as by the absence of reparative (tertiary) dentine inside the pulp cavity at the late stage of tooth functioning. The morphology of the holotype reveals that D. gigantea is a valid species and the third representative of the group after Ulemosaurus svijagensis and U. gigas, to be described from Eastern Europe. Judging from the Ocher age of the type locality, D. gigantea is the oldest-known tapinocephaloid known from the tetrapod assemblages of the region.
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Free pdf:
Acheloma cryptatheria sp. nov.
Adrian F. Osterling Arias, Ethan D. Mooney, Joseph J. Bevitt & Robert R. Reisz (2024)
A new trematopid from the lower Permian of Oklahoma and new insights into the genus Acheloma.
PLoS ONE 19(10): e0309393
doi: https://doi.org/10.1371/journal.pone.0309393
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0309393
Modern-day terrestrial amphibians pale in comparison to their monstrous ancient relatives, the Late Carboniferous and Early Permian trematopid temnospondyls. With a skeleton that clearly indicated a terrestrial mode of life and armed with an impressive set of large, recurved marginal dentition and palatal fangs for holding their prey—this group of terrestrial temnospondyls roamed North America and Central Europe as a top predator. Lack of substantial informative fossil material has previously limited our understanding of trematopid diversity and ontogeny. Fortunately, this has improved in the last few decades with the help of exceptional localities like the Early Permian locality Richards Spur. While multiple species of dissorophid temnospondyl have been described from Richards Spur, only one trematopid species has been confidently recognized -Acheloma dunni. Here, we report on the presence of a new large, relatively mature trematopid skull from this famous locality, found encased within a limestone rich block composed mostly of skeletal remains from several other taxa. With the help of neutron computed tomography (nCT), a non-invasive method of analyzing internal and external morphologies, this specimen has revealed several features consistent with the genus, Acheloma, but distinct from Acheloma cumminsi and Acehloma dunni. The identification of these new features, in addition to the characters it shares with other Acheloma species, not only constitute it as a new species of this genus, but also challenges the notion of having synonymized Acheloma dunni with Acheloma cumminsi. In this study, we also unveil new anatomical characters that are potentially independent of ontogeny and could therefore help clarify some of the phylogenetic relationships of this fascinating group of Paleozoic terrestrial predators.
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