Manistropheus, new archosauromorph from Permian of Germany + Triassic cynognathian body mass estimations
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Ben Creisler
Jul 8, 2025, 11:38:32 AM7/8/25
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Ben Creisler
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New papers:
https://zoobank.org/urn:lsid:zoobank.org:pub:9CC99EAD-5214-4707-A79D-B3332E91E128
The archosauromorphs (birds, crocodylians, and reptiles closer to them than to lepidosauromorphs) are major components of the extant tetrapod biodiversity, and their major diversification started during the Triassic. The oldest archosauromorphs are late Permian in age, but their record from this time interval is currently limited to five nominal species and a few other possible occurrences. Brief reports of probable archosauromorph skeletal remains from an upper Permian fissure filling just south of Korbach in Hesse (Germany) can potentially increase the scarce Palaeozoic record of the clade. Here we describe and compare an isolated anterior postaxial cervical vertebra from the Korbach locality (SMNK-PAL 76022). The vertebra has a parallelogram-shaped elongated centrum, which is 2.5 times longer than tall, and a low neural spine, resembling the morphology of other early archosauromorphs. In addition, a lunate fossa that separates the anterior rim of the centrum from the base of the prezygapophysis and the absence of posteriorly well-defined prezygapophyseal facets appear to be unique among Permo-Triassic diapsids and allow SMNK-PAL 76022 to be designated as the holotype of the new genus and species Manistropheus kulicki. A comprehensive phylogenetic analysis recovered Manistropheus kulicki at the base of Archosauromorpha. Morphological disparity analyses based on anterior-middle postaxial cervical characters show that Permian archosauromorphs taken together were already diverse before the end-Permian mass extinction (EPME). The cervical morphological disparity is low during the immediate aftermath of the EPME, but it increases during the late Induan and subsequently reaches a plateau of high values. This represents a faster diversification of this part of the skeleton after the EPME than has been found for other skeletal regions in previous studies. Manistropheus kulicki uncovers a small portion of the purported cryptic Permian archosauromorph diversity and highlights the importance of the Korbach locality to shed light on the continental tetrapod assemblages before the EPME.
Manistropheus kulicki gen. et. sp. nov.
Martín D. Ezcurra, Hans-Dieter Sues & Jörg Fröbisch (2025)
A new late Permian archosauromorph reptile from Germany enhances our understanding of the early diversity of the clade
Journal of Systematic Palaeontology 23(1): 2509639
doi: https://doi.org/10.1080/14772019.2025.2509639
https://www.tandfonline.com/doi/full/10.1080/14772019.2025.2509639
Martín D. Ezcurra, Hans-Dieter Sues & Jörg Fröbisch (2025)
A new late Permian archosauromorph reptile from Germany enhances our understanding of the early diversity of the clade
Journal of Systematic Palaeontology 23(1): 2509639
doi: https://doi.org/10.1080/14772019.2025.2509639
https://www.tandfonline.com/doi/full/10.1080/14772019.2025.2509639
https://zoobank.org/urn:lsid:zoobank.org:pub:9CC99EAD-5214-4707-A79D-B3332E91E128
The archosauromorphs (birds, crocodylians, and reptiles closer to them than to lepidosauromorphs) are major components of the extant tetrapod biodiversity, and their major diversification started during the Triassic. The oldest archosauromorphs are late Permian in age, but their record from this time interval is currently limited to five nominal species and a few other possible occurrences. Brief reports of probable archosauromorph skeletal remains from an upper Permian fissure filling just south of Korbach in Hesse (Germany) can potentially increase the scarce Palaeozoic record of the clade. Here we describe and compare an isolated anterior postaxial cervical vertebra from the Korbach locality (SMNK-PAL 76022). The vertebra has a parallelogram-shaped elongated centrum, which is 2.5 times longer than tall, and a low neural spine, resembling the morphology of other early archosauromorphs. In addition, a lunate fossa that separates the anterior rim of the centrum from the base of the prezygapophysis and the absence of posteriorly well-defined prezygapophyseal facets appear to be unique among Permo-Triassic diapsids and allow SMNK-PAL 76022 to be designated as the holotype of the new genus and species Manistropheus kulicki. A comprehensive phylogenetic analysis recovered Manistropheus kulicki at the base of Archosauromorpha. Morphological disparity analyses based on anterior-middle postaxial cervical characters show that Permian archosauromorphs taken together were already diverse before the end-Permian mass extinction (EPME). The cervical morphological disparity is low during the immediate aftermath of the EPME, but it increases during the late Induan and subsequently reaches a plateau of high values. This represents a faster diversification of this part of the skeleton after the EPME than has been found for other skeletal regions in previous studies. Manistropheus kulicki uncovers a small portion of the purported cryptic Permian archosauromorph diversity and highlights the importance of the Korbach locality to shed light on the continental tetrapod assemblages before the EPME.
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F. S. Filippini, F. Abdala & G. H. Cassini (2025)
Body mass estimation in Triassic Cynognathia (Therapsida, Cynodontia) from South America based on 3d craniomandibular landmarks
HIstorical Biology (advance online publication)
doi: https://doi.org/10.1080/08912963.2025.2527804
https://www.tandfonline.com/doi/full/10.1080/08912963.2025.2527804
Body size is one of the main proxies for understanding the biological aspects of fossil vertebrates. Body masses of five species of Cynognathia were obtained from 3D configurations of cranial and mandibular landmarks from 29 specimens. Equations based on centroid size from the literature of ungulates and calculated from carnivorous mammal database were used. In addition, the maximum size per species was obtained by geometric similarity and compared with estimates based on postcranial elements from recent literature. The values of body mass obtained from the centroid size do not present major discrepancies with those obtained from the postcranium, except in the larger specimens of Massetognathus and Exaeretodon. Geometric similarity is useful as a comparative method and for detecting over- or underestimates. Larger size ranges than previously reported were recorded for each cynognathian species. Among the small species, Andescynodon ranged from 1 to 6.5 kg and Pascualgnathus, 2.5 to 6 kg; medium-sized Massetognathus, 10 to 30 kg; and the large species, Cynognathus ranged 100 to 150 kg and Exaeretodon, 100 to 280 kg. The relationship between diet and body mass observed in extant mammals was used as a comparison to determine the possible ecological niche of cynognathians.
Body mass estimation in Triassic Cynognathia (Therapsida, Cynodontia) from South America based on 3d craniomandibular landmarks
HIstorical Biology (advance online publication)
doi: https://doi.org/10.1080/08912963.2025.2527804
https://www.tandfonline.com/doi/full/10.1080/08912963.2025.2527804
Body size is one of the main proxies for understanding the biological aspects of fossil vertebrates. Body masses of five species of Cynognathia were obtained from 3D configurations of cranial and mandibular landmarks from 29 specimens. Equations based on centroid size from the literature of ungulates and calculated from carnivorous mammal database were used. In addition, the maximum size per species was obtained by geometric similarity and compared with estimates based on postcranial elements from recent literature. The values of body mass obtained from the centroid size do not present major discrepancies with those obtained from the postcranium, except in the larger specimens of Massetognathus and Exaeretodon. Geometric similarity is useful as a comparative method and for detecting over- or underestimates. Larger size ranges than previously reported were recorded for each cynognathian species. Among the small species, Andescynodon ranged from 1 to 6.5 kg and Pascualgnathus, 2.5 to 6 kg; medium-sized Massetognathus, 10 to 30 kg; and the large species, Cynognathus ranged 100 to 150 kg and Exaeretodon, 100 to 280 kg. The relationship between diet and body mass observed in extant mammals was used as a comparison to determine the possible ecological niche of cynognathians.
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