Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolution
Millerettidae are a group of superficially lizard-like Permian stem reptiles originally hypothesized as relevant to the ancestry of the reptile crown group, and particularly to lepidosaurs and archosaurs. Since the advent of cladistics, millerettids have typically been considered to be more distant...
Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
The Royal Society
2025-01-01
|
| Series: | Royal Society Open Science |
| Subjects: | |
| Online Access: | https://royalsocietypublishing.org/doi/10.1098/rsos.241298 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1841554662654738432 |
|---|---|
| author | Xavier A. Jenkins Roger B. J. Benson David P. Ford Claire Browning Vincent Fernandez Elizabeth Griffiths Jonah Choiniere Brandon R. Peecook |
| author_facet | Xavier A. Jenkins Roger B. J. Benson David P. Ford Claire Browning Vincent Fernandez Elizabeth Griffiths Jonah Choiniere Brandon R. Peecook |
| author_sort | Xavier A. Jenkins |
| collection | DOAJ |
| description | Millerettidae are a group of superficially lizard-like Permian stem reptiles originally hypothesized as relevant to the ancestry of the reptile crown group, and particularly to lepidosaurs and archosaurs. Since the advent of cladistics, millerettids have typically been considered to be more distant relatives of crown reptiles as the earliest-diverging parareptiles and therefore outside of ‘Eureptilia’. Despite this cladistic consensus, some conspicuous features of millerettid anatomy invite reconsideration of their relationships. We provide a detailed description of the late Permian millerettid Milleropsis pricei using synchrotron X-ray phase-contrast micro-computed tomography focusing on the cranial anatomy of three individuals known from a burrow aggregation. Our data reveal a suite of neuroanatomical features Milleropsis shares with neodiapsids that are absent both in other ‘parareptiles’ and in early diverging groups of ‘eureptiles’. Traits shared between Milleropsis and neodiapsids include: the presence of a tympanic emargination on the quadrate, quadratojugal and squamosal, the loss of epipterygoid contribution to the basicranial articulation suggesting a more kinetic palatoquadrate, the absence of a sphenethmoid and the pathway of the abducens nerve through the braincase. Our findings suggest that the early reptile neurocranium, a region poorly sampled in phylogenetic analyses due to relative visual inaccessibility and poor preservation, has the potential to inform the phylogenetic relationships of early reptiles. |
| format | Article |
| id | doaj-art-c9e8b3b0b6ec4fcf9b730ecfa811258e |
| institution | Kabale University |
| issn | 2054-5703 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | The Royal Society |
| record_format | Article |
| series | Royal Society Open Science |
| spelling | doaj-art-c9e8b3b0b6ec4fcf9b730ecfa811258e2025-01-08T11:55:59ZengThe Royal SocietyRoyal Society Open Science2054-57032025-01-0112110.1098/rsos.241298Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolutionXavier A. Jenkins0Roger B. J. Benson1David P. Ford2Claire Browning3Vincent Fernandez4Elizabeth Griffiths5Jonah Choiniere6Brandon R. Peecook7Department of Biological Sciences, Idaho State University, Pocatello, Idaho, USAAmerican Museum of Natural History, New York NY, USAEvolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South AfricaIziko Museums of South Africa, P.O. Box 61, Cape Town 8000, South AfricaEvolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South AfricaDepartment of Earth Sciences, University of Oxford, Oxford, UKEvolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South AfricaDepartment of Biological Sciences, Idaho State University, Pocatello, Idaho, USAMillerettidae are a group of superficially lizard-like Permian stem reptiles originally hypothesized as relevant to the ancestry of the reptile crown group, and particularly to lepidosaurs and archosaurs. Since the advent of cladistics, millerettids have typically been considered to be more distant relatives of crown reptiles as the earliest-diverging parareptiles and therefore outside of ‘Eureptilia’. Despite this cladistic consensus, some conspicuous features of millerettid anatomy invite reconsideration of their relationships. We provide a detailed description of the late Permian millerettid Milleropsis pricei using synchrotron X-ray phase-contrast micro-computed tomography focusing on the cranial anatomy of three individuals known from a burrow aggregation. Our data reveal a suite of neuroanatomical features Milleropsis shares with neodiapsids that are absent both in other ‘parareptiles’ and in early diverging groups of ‘eureptiles’. Traits shared between Milleropsis and neodiapsids include: the presence of a tympanic emargination on the quadrate, quadratojugal and squamosal, the loss of epipterygoid contribution to the basicranial articulation suggesting a more kinetic palatoquadrate, the absence of a sphenethmoid and the pathway of the abducens nerve through the braincase. Our findings suggest that the early reptile neurocranium, a region poorly sampled in phylogenetic analyses due to relative visual inaccessibility and poor preservation, has the potential to inform the phylogenetic relationships of early reptiles.https://royalsocietypublishing.org/doi/10.1098/rsos.241298osteologyneuroanatomylate PermianReptilia |
| spellingShingle | Xavier A. Jenkins Roger B. J. Benson David P. Ford Claire Browning Vincent Fernandez Elizabeth Griffiths Jonah Choiniere Brandon R. Peecook Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolution Royal Society Open Science osteology neuroanatomy late Permian Reptilia |
| title | Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolution |
| title_full | Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolution |
| title_fullStr | Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolution |
| title_full_unstemmed | Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolution |
| title_short | Cranial osteology and neuroanatomy of the late Permian reptile Milleropsis pricei and implications for early reptile evolution |
| title_sort | cranial osteology and neuroanatomy of the late permian reptile milleropsis pricei and implications for early reptile evolution |
| topic | osteology neuroanatomy late Permian Reptilia |
| url | https://royalsocietypublishing.org/doi/10.1098/rsos.241298 |
| work_keys_str_mv | AT xavierajenkins cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution AT rogerbjbenson cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution AT davidpford cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution AT clairebrowning cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution AT vincentfernandez cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution AT elizabethgriffiths cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution AT jonahchoiniere cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution AT brandonrpeecook cranialosteologyandneuroanatomyofthelatepermianreptilemilleropsispriceiandimplicationsforearlyreptileevolution |