Pub Date : 2021-10-02DOI: 10.1080/14772019.2022.2035440
M. J. Van den Brandt, F. Abdala, J. Benoit, M. Day, David P. Groenewald, B. Rubidge
Pareiasaurs were relatively abundant, globally-distributed, herbivorous parareptiles of the mid to late Permian. The basal-most forms, all members of the Bradysauria, are restricted to the Guadalupian (mid-Permian) of South Africa and went extinct in the late Capitanian near the top of the Tapinocephalus Assemblage Zone. Currently four species are recognized in this group: Bradysaurus seeleyi, B. baini, Embrithosaurus schwarzi and Nochelesaurus alexanderi. These taxa have been poorly defined historically and based on a limited number of specimens, leaving the taxonomic diversity of the group open to doubt and limiting their utility in biostratigraphy. Here, we present our fourth and final contribution to improve the understanding of this group by providing a taxonomical and phylogenetic review, updated stratigraphical ranges, and updated diagnoses for each taxon within Bradysauria. Bradysaurus seeleyi is synonymized with Bradysaurus baini, resulting in three valid mid-Permian pareiasaur taxa: Bradysaurus baini, Embrithosaurus schwarzi and Nochelesaurus alexanderi. Our cladistic analysis of cranial and postcranial characters supports the monophyly of Bradysauria with five synapomorphies. Embrithosaurus schwarzi is recovered as the sister taxon to a clade containing Bradysaurus baini and Nochelesaurus alexanderi. By identifying 157 pareiasaur specimens in fossil collections we show that the Bradysauria are stratigraphically restricted to the Abrahamskraal Formation of the Beaufort Group and suggest a staggered appearance. Bradysaurus baini is first to appear, followed by Nochelesaurus alexanderi, and lastly by Embrithosaurus schwarzi. All three taxa perished during the Capitanian mass extinction, and have their highest occurrences near the top of the Abrahamskraal Formation.
{"title":"Taxonomy, phylogeny and stratigraphical ranges of middle Permian pareiasaurs from the Karoo Basin of South Africa","authors":"M. J. Van den Brandt, F. Abdala, J. Benoit, M. Day, David P. Groenewald, B. Rubidge","doi":"10.1080/14772019.2022.2035440","DOIUrl":"https://doi.org/10.1080/14772019.2022.2035440","url":null,"abstract":"Pareiasaurs were relatively abundant, globally-distributed, herbivorous parareptiles of the mid to late Permian. The basal-most forms, all members of the Bradysauria, are restricted to the Guadalupian (mid-Permian) of South Africa and went extinct in the late Capitanian near the top of the Tapinocephalus Assemblage Zone. Currently four species are recognized in this group: Bradysaurus seeleyi, B. baini, Embrithosaurus schwarzi and Nochelesaurus alexanderi. These taxa have been poorly defined historically and based on a limited number of specimens, leaving the taxonomic diversity of the group open to doubt and limiting their utility in biostratigraphy. Here, we present our fourth and final contribution to improve the understanding of this group by providing a taxonomical and phylogenetic review, updated stratigraphical ranges, and updated diagnoses for each taxon within Bradysauria. Bradysaurus seeleyi is synonymized with Bradysaurus baini, resulting in three valid mid-Permian pareiasaur taxa: Bradysaurus baini, Embrithosaurus schwarzi and Nochelesaurus alexanderi. Our cladistic analysis of cranial and postcranial characters supports the monophyly of Bradysauria with five synapomorphies. Embrithosaurus schwarzi is recovered as the sister taxon to a clade containing Bradysaurus baini and Nochelesaurus alexanderi. By identifying 157 pareiasaur specimens in fossil collections we show that the Bradysauria are stratigraphically restricted to the Abrahamskraal Formation of the Beaufort Group and suggest a staggered appearance. Bradysaurus baini is first to appear, followed by Nochelesaurus alexanderi, and lastly by Embrithosaurus schwarzi. All three taxa perished during the Capitanian mass extinction, and have their highest occurrences near the top of the Abrahamskraal Formation.","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1367 - 1393"},"PeriodicalIF":2.6,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49575160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/14772019.2022.2033861
T. Přikryl, J. Kaur, Alison M. Murray
Two species of fossil cichlid are described from Oligocene deposits of Libya. One is formally described as Libyachromis fugacior gen. et sp. nov. This species is considered to be the sister group to most of the remaining members of the African subfamily Pseudocrenilabrinae, perhaps close to Heterochromis, and is characterized by two predorsal bones, dorsal fin with 12–14 spines and 9–12 rays, 24–28 vertebrae, cycloid scales present on body and head including cheek, and only unicuspid teeth present on the oral and pharyngeal jaws. The second fossil form is less complete, and so we do not formally name it, but it appears to be most closely related to Tylochromis, and thus we place it in the Tylochromini. These new fossils increase our understanding of the diversity of cichlid lineages in the Palaeogene. The unnamed fossil supports the presence of Tylochromini in the Eocene and Oligocene of North Africa, as was previously suggested by the remains of partial lower pharyngeal jaws from Egypt and Libya. The named fossil adds to the known diversity of early Cenozoic cichlids that document the presence of probably Heterochromini along with Tylochromini in North Africa. http://zoobank.org/urn:lsid:zoobank.org:pub:435CD980-E4DB-4333-AB21-BDA38F9C6023
{"title":"New Oligocene Pseudocrenilabrinae cichlid fishes (Teleostei, Cichlidae) from freshwater deposits of Libya","authors":"T. Přikryl, J. Kaur, Alison M. Murray","doi":"10.1080/14772019.2022.2033861","DOIUrl":"https://doi.org/10.1080/14772019.2022.2033861","url":null,"abstract":"Two species of fossil cichlid are described from Oligocene deposits of Libya. One is formally described as Libyachromis fugacior gen. et sp. nov. This species is considered to be the sister group to most of the remaining members of the African subfamily Pseudocrenilabrinae, perhaps close to Heterochromis, and is characterized by two predorsal bones, dorsal fin with 12–14 spines and 9–12 rays, 24–28 vertebrae, cycloid scales present on body and head including cheek, and only unicuspid teeth present on the oral and pharyngeal jaws. The second fossil form is less complete, and so we do not formally name it, but it appears to be most closely related to Tylochromis, and thus we place it in the Tylochromini. These new fossils increase our understanding of the diversity of cichlid lineages in the Palaeogene. The unnamed fossil supports the presence of Tylochromini in the Eocene and Oligocene of North Africa, as was previously suggested by the remains of partial lower pharyngeal jaws from Egypt and Libya. The named fossil adds to the known diversity of early Cenozoic cichlids that document the presence of probably Heterochromini along with Tylochromini in North Africa. http://zoobank.org/urn:lsid:zoobank.org:pub:435CD980-E4DB-4333-AB21-BDA38F9C6023","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1343 - 1366"},"PeriodicalIF":2.6,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44978132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/14772019.2022.2029595
Chenchen Shen, G. Arratia
Wushaichthys exquisitus, a small fish from the Ladinian of Xingyi, Guizhou Province, southern China, was named a few years ago and interpreted as the most primitive species in the Thoracopteridae (Triassic ‘flying’ fishes with a Euro-Asian distribution). However, this hypothesis was questioned, because Wushaichthys also shares features with Peltopleuridae. A detailed morphological re-description of Wushaichthys was conducted based on new specimens, plus a revision of previously studied ones, as well as of members of Peripeltopleurus and thoracopterids, and their relationships were tested with a phylogenetic analysis based on 137 characters and 54 taxa. The results suggest that Wushaichthys is a member of a clade that is interpreted here as the new superfamily Thoracopteroidea, which contains Wushaichthyidae fam. nov. (Wushaichthys + Peripeltopleurus) and Thoracopteridae and is the sister taxon of the non-monophyletic Peltopleuridae among Peltopleuriformes. Thoracopteroidea superfam. nov. is strongly supported by numerous synapomorphies (e.g. frontal (= parietal) bone slightly expanded laterally; posttemporal contacts the extrascapular anterolaterally separating it from its counterpart; suspensorium is vertically oriented; narrow and deep rectangular preopercle, vertically oriented; preopercle sutured with the rear edge of the maxilla throughout the maxillary process; enlarged pectoral fins in most genera; and deeply forked hypocercal caudal fin). Although Thoracopteridae is monophyletic, one of its genera, Thoracopterus, is not. Consequently, the content of Thoracopteridae was re-evaluated and now includes Thoracopterus, Gigantopterus, Potanichthys comb. nov. and Italopterus gen. nov. Wushaichthyidae is supported by a unique combination of characters, and the results confirm it as a thoracopteroid, but not a thoracopterid. The characters of Wushaichthys are relevant for understanding the taxonomy and systematics of thoracopteroids, especially the evolutionary morphological modifications of the pectoral and pelvic fins and the lower lobe of the caudal fin, which are some of the main characters of these fishes. http://zoobank.org/urn:lsid:zoobank.org:pub:8FFF4E8D-780C-4DFB-B0C8-7E27D912CE8E
{"title":"Re-description of the sexually dimorphic peltopleuriform fish Wushaichthys exquisitus (Middle Triassic, China): taxonomic implications and phylogenetic relationships","authors":"Chenchen Shen, G. Arratia","doi":"10.1080/14772019.2022.2029595","DOIUrl":"https://doi.org/10.1080/14772019.2022.2029595","url":null,"abstract":"Wushaichthys exquisitus, a small fish from the Ladinian of Xingyi, Guizhou Province, southern China, was named a few years ago and interpreted as the most primitive species in the Thoracopteridae (Triassic ‘flying’ fishes with a Euro-Asian distribution). However, this hypothesis was questioned, because Wushaichthys also shares features with Peltopleuridae. A detailed morphological re-description of Wushaichthys was conducted based on new specimens, plus a revision of previously studied ones, as well as of members of Peripeltopleurus and thoracopterids, and their relationships were tested with a phylogenetic analysis based on 137 characters and 54 taxa. The results suggest that Wushaichthys is a member of a clade that is interpreted here as the new superfamily Thoracopteroidea, which contains Wushaichthyidae fam. nov. (Wushaichthys + Peripeltopleurus) and Thoracopteridae and is the sister taxon of the non-monophyletic Peltopleuridae among Peltopleuriformes. Thoracopteroidea superfam. nov. is strongly supported by numerous synapomorphies (e.g. frontal (= parietal) bone slightly expanded laterally; posttemporal contacts the extrascapular anterolaterally separating it from its counterpart; suspensorium is vertically oriented; narrow and deep rectangular preopercle, vertically oriented; preopercle sutured with the rear edge of the maxilla throughout the maxillary process; enlarged pectoral fins in most genera; and deeply forked hypocercal caudal fin). Although Thoracopteridae is monophyletic, one of its genera, Thoracopterus, is not. Consequently, the content of Thoracopteridae was re-evaluated and now includes Thoracopterus, Gigantopterus, Potanichthys comb. nov. and Italopterus gen. nov. Wushaichthyidae is supported by a unique combination of characters, and the results confirm it as a thoracopteroid, but not a thoracopterid. The characters of Wushaichthys are relevant for understanding the taxonomy and systematics of thoracopteroids, especially the evolutionary morphological modifications of the pectoral and pelvic fins and the lower lobe of the caudal fin, which are some of the main characters of these fishes. http://zoobank.org/urn:lsid:zoobank.org:pub:8FFF4E8D-780C-4DFB-B0C8-7E27D912CE8E","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1317 - 1342"},"PeriodicalIF":2.6,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43575196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-17DOI: 10.1080/14772019.2022.2036837
Jack Stack, M. Gottfried
The evolutionary history of Palaeozoic and early Mesozoic ray-finned fishes (Actinopterygii) is obscured by an incomplete fossil record and under-study of late Palaeozoic (Permo-Carboniferous) actinopterygians. To help address this issue, we describe a new species of ray-finned fish, Concentrilepis minnekahtaensis gen. et sp. nov., from the late early Permian (Kungurian) Minnekahta Limestone of South Dakota (USA). This taxon is represented by Field Museum of Natural History FMNH PF 3721, an exceptionally well-preserved partial three-dimensional head and trunk preserving the external anatomy and some internal elements from the skull, paired fins and scale cover. Concentrilepis is also represented by Yale Peabody Museum 18649, a laterally compressed individual that preserves the posterior portion of the body. This taxon has features of the paraphyletic ‘paleoniscoids’, including an immobile maxilla with a narrow suborbital process and a broad postorbital expansion, a heterocercal caudal fin, and rhombic ganoid scales. Concentrilepis is distinguished from similar species by the dual lateral expansions on its frontal (= parietal of sarcopterygians), the exclusion of the lacrimal from the oral margin, and lateral scales that are longer than deep and ornamented with straight, concentric ridges at their margins and diagonal ridges at their centres. We conducted a maximum parsimony analysis in PAUP and a Bayesian analysis with the Mkv model in MrBayes with 73 other taxa and 222 characters that placed this taxon in a polytomy with other late Palaeozoic and early Mesozoic ‘paleoniscoids’. We also found that the application of Bayesian and parsimony techniques in tandem provided the necessary caution in interpreting our results and focused direction for future study. Continued efforts to gather more morphological data from ‘paleoniscoids’ in concert with the development and testing of novel phylogenetic characters and inference techniques will be necessary to improve our understanding of the interrelationships of late Palaeozoic and early Mesozoic actinopterygians. http://zoobank.org/urn:lsid:zoobank.org:pub:9F12F99D-A33A-41C2-AC34-F4936786020B
由于化石记录的不完整和对晚古生代(二叠纪-石炭纪)放光鳍鱼的研究不足，使得古生代和中生代早期放光鳍鱼的进化史模糊不清。为了帮助解决这个问题，我们描述了一种新的鳐鱼，Concentrilepis minnekahtaensis gen. et sp. nov.，来自南达科他州(美国)早二叠纪晚期(Kungurian)的明尼卡塔石灰岩。该分类群由菲尔德自然历史博物馆FMNH PF 3721代表，这是一个保存非常完好的部分三维头部和躯干，保留了外部解剖结构和头骨的一些内部元素，成对的鳍和鳞片盖。18649年耶鲁皮博迪博物馆也展出了Concentrilepis，这是一个侧面压缩的个体，保留了身体的后部。该分类群具有准进化的“古石器类”的特征，包括固定的上颌骨，狭窄的眶下突和宽阔的眶后扩张，尾鳍呈异角状，鳞片呈菱形。它与同类的区别在于其额部有双侧面的扩张(=肉翅目的顶骨)，口缘没有泪片，侧面鳞片长于深，边缘有直的同心脊，中心有对角脊。利用PAUP和MrBayes的Mkv模型对73个分类群和222个性状进行了最大简约性分析和贝叶斯分析，将该分类群与其他晚古生代和早中生代的“古生代类群”置于一个多边形中。我们还发现，贝叶斯和简约技术的应用为解释我们的结果和未来研究的重点方向提供了必要的谨慎。为了进一步了解晚古生代和早中生代放光翼类动物之间的相互关系，有必要继续努力从“古生代类”中收集更多的形态数据，并开发和测试新的系统发育特征和推断技术。http://zoobank.org/urn:lsid:zoobank.org:pub:9F12F99D-A33A-41C2-AC34-F4936786020B
{"title":"A new, exceptionally well-preserved Permian actinopterygian fish from the Minnekahta Limestone of South Dakota, USA","authors":"Jack Stack, M. Gottfried","doi":"10.1080/14772019.2022.2036837","DOIUrl":"https://doi.org/10.1080/14772019.2022.2036837","url":null,"abstract":"The evolutionary history of Palaeozoic and early Mesozoic ray-finned fishes (Actinopterygii) is obscured by an incomplete fossil record and under-study of late Palaeozoic (Permo-Carboniferous) actinopterygians. To help address this issue, we describe a new species of ray-finned fish, Concentrilepis minnekahtaensis gen. et sp. nov., from the late early Permian (Kungurian) Minnekahta Limestone of South Dakota (USA). This taxon is represented by Field Museum of Natural History FMNH PF 3721, an exceptionally well-preserved partial three-dimensional head and trunk preserving the external anatomy and some internal elements from the skull, paired fins and scale cover. Concentrilepis is also represented by Yale Peabody Museum 18649, a laterally compressed individual that preserves the posterior portion of the body. This taxon has features of the paraphyletic ‘paleoniscoids’, including an immobile maxilla with a narrow suborbital process and a broad postorbital expansion, a heterocercal caudal fin, and rhombic ganoid scales. Concentrilepis is distinguished from similar species by the dual lateral expansions on its frontal (= parietal of sarcopterygians), the exclusion of the lacrimal from the oral margin, and lateral scales that are longer than deep and ornamented with straight, concentric ridges at their margins and diagonal ridges at their centres. We conducted a maximum parsimony analysis in PAUP and a Bayesian analysis with the Mkv model in MrBayes with 73 other taxa and 222 characters that placed this taxon in a polytomy with other late Palaeozoic and early Mesozoic ‘paleoniscoids’. We also found that the application of Bayesian and parsimony techniques in tandem provided the necessary caution in interpreting our results and focused direction for future study. Continued efforts to gather more morphological data from ‘paleoniscoids’ in concert with the development and testing of novel phylogenetic characters and inference techniques will be necessary to improve our understanding of the interrelationships of late Palaeozoic and early Mesozoic actinopterygians. http://zoobank.org/urn:lsid:zoobank.org:pub:9F12F99D-A33A-41C2-AC34-F4936786020B","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1271 - 1302"},"PeriodicalIF":2.6,"publicationDate":"2021-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42372934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-17DOI: 10.1080/14772019.2022.2042409
Yanchao Luo, Xindong Cui, Tuo Qiao, Min Zhu
A new genus and species of tooth-plated lungfishes, Dianodipterus huizeensis gen. et sp. nov., is described from the Qujing Formation (late Eifelian, Middle Devonian) of Huize County, Qujing, north-eastern Yunnan, China. It differs from other lungfishes in the small proportion of the tooth-bearing part on the pterygoid (less than one-quarter), the extensively developed anteromedial edentulous portion of the pterygoid, and tooth rows few in number (only four). Phylogenetic analysis reveals that Dianodipterus is more plesiomorphic than Dipterus, yet crownward of Melanognathus. As the ninth Devonian lungfish genus from China, the new taxon displays a novel schema of lungfish dentition and increases the diversity of early lungfishes. http://zoobank.org/urn:lsid:zoobank.org:pub:207B0E6E-EBBF-4E92-83F4-78FDAD6EBB60
云南东北曲靖会泽县曲靖组(中泥盆世eifel世晚期)有齿肺鱼Dianodipterus huizeensis gen. et sp. nov.一新属和新种。它与其他肺鱼的不同之处在于翼状骨上有牙齿的部分所占的比例很小(不到四分之一)，翼状骨的前内侧无牙部分发育广泛，齿列数量很少(只有四列)。系统发育分析表明，Dianodipterus比Dipterus更接近半形，但在Melanognathus的上方。作为中国泥盆纪第9个肺鱼属，这一新分类群显示了一种新的肺鱼齿列模式，增加了早期肺鱼的多样性。http://zoobank.org/urn:lsid:zoobank.org:pub:207B0E6E-EBBF-4E92-83F4-78FDAD6EBB60
{"title":"A new dipnoan genus from the Middle Devonian of Huize, Yunnan, China","authors":"Yanchao Luo, Xindong Cui, Tuo Qiao, Min Zhu","doi":"10.1080/14772019.2022.2042409","DOIUrl":"https://doi.org/10.1080/14772019.2022.2042409","url":null,"abstract":"A new genus and species of tooth-plated lungfishes, Dianodipterus huizeensis gen. et sp. nov., is described from the Qujing Formation (late Eifelian, Middle Devonian) of Huize County, Qujing, north-eastern Yunnan, China. It differs from other lungfishes in the small proportion of the tooth-bearing part on the pterygoid (less than one-quarter), the extensively developed anteromedial edentulous portion of the pterygoid, and tooth rows few in number (only four). Phylogenetic analysis reveals that Dianodipterus is more plesiomorphic than Dipterus, yet crownward of Melanognathus. As the ninth Devonian lungfish genus from China, the new taxon displays a novel schema of lungfish dentition and increases the diversity of early lungfishes. http://zoobank.org/urn:lsid:zoobank.org:pub:207B0E6E-EBBF-4E92-83F4-78FDAD6EBB60","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1303 - 1315"},"PeriodicalIF":2.6,"publicationDate":"2021-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44822993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-17DOI: 10.1080/14772019.2022.2028025
A. Pérez‐García, M. Martín-Jiménez, E. Vlachos, V. Codrea
The genus Testudo was considered, for more than two centuries, to group almost all tortoises that are part of current biodiversity (i.e. the members of Testudinidae), as well as the extinct representatives of that successful lineage. However, only three extant species, as well as scarce late Miocene to late Pliocene extinct ones, are now considered attributable to that genus. The fossil record of the extinct representatives is restricted to postcranial elements. They correspond almost exclusively to shells or partial shells, most of the species being known on the basis of only one individual. Abundant material of testudinids from the late Miocene of eastern Romania (Crețești 1 fossil site, Vaslui County) is presented here. This material is attributable to Testudo, representing a new species. This find is not only relevant for the abundance of specimens, but they stand out for their unusually good preservation. Most of them are represented by partial skeletons, preserving not only several bones in anatomical connection but also some regions of the peculiar ossified dermal armour that covered their limbs. Two of these skeletons preserve the skull, which allows us to perform both the first three-dimensional reconstruction of the cranial anatomy and the first neuroanatomical study of an extinct member of Testudo. The best-preserved extinct species of the reference genus of the only extant lineage of tortoises (i.e. Testudinidae), Testudo lohanica sp. nov., is characterized in detail.
{"title":"The most complete extinct species of Testudo (Testudines, Testudinidae) defined by several well-preserved skeletons from the late Miocene of Romania","authors":"A. Pérez‐García, M. Martín-Jiménez, E. Vlachos, V. Codrea","doi":"10.1080/14772019.2022.2028025","DOIUrl":"https://doi.org/10.1080/14772019.2022.2028025","url":null,"abstract":"The genus Testudo was considered, for more than two centuries, to group almost all tortoises that are part of current biodiversity (i.e. the members of Testudinidae), as well as the extinct representatives of that successful lineage. However, only three extant species, as well as scarce late Miocene to late Pliocene extinct ones, are now considered attributable to that genus. The fossil record of the extinct representatives is restricted to postcranial elements. They correspond almost exclusively to shells or partial shells, most of the species being known on the basis of only one individual. Abundant material of testudinids from the late Miocene of eastern Romania (Crețești 1 fossil site, Vaslui County) is presented here. This material is attributable to Testudo, representing a new species. This find is not only relevant for the abundance of specimens, but they stand out for their unusually good preservation. Most of them are represented by partial skeletons, preserving not only several bones in anatomical connection but also some regions of the peculiar ossified dermal armour that covered their limbs. Two of these skeletons preserve the skull, which allows us to perform both the first three-dimensional reconstruction of the cranial anatomy and the first neuroanatomical study of an extinct member of Testudo. The best-preserved extinct species of the reference genus of the only extant lineage of tortoises (i.e. Testudinidae), Testudo lohanica sp. nov., is characterized in detail.","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1237 - 1270"},"PeriodicalIF":2.6,"publicationDate":"2021-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47171272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-02DOI: 10.1080/14772019.2021.2015470
Tao Yang, Weiyu Liang, Jiahao Cai, H. Gu, Lei Han, Hongyu Chen, Haojian Wang, Lin Bao, De-Fei Yan
The Qaidam Basin, lying in the north-eastern Tibetan Plateau, China, is key to understanding the Cenozoic climatic and biological changes that have occurred on the plateau; however, information from a palaeontological perspective on this Palaeogene basin is scant. Recently, fossil cyprinids were found in the middle portion of the Shangganchaigou Formation (= Upper Ganchaigou Formation; Oligocene) in the north-western Qaidam Basin. These share many osteological characters with barbines and ‘morphologically primitive clade schizothoracines’ (= primitive schizothoracines; i.e. Schizothorax and Aspiorhynchus), and they closely resemble the latter in the size and shape of the scales: body scales are small and oval; the number of lateral line scales exceeds 100; and the long-oval scales from the pre-anal region are very similar to the ‘anal scales’, which are unique to schizothoracines. Compared with another fossil fish, Paleoschizothorax qaidamensis, from the same formation, the major differences are: (1) the posterior part of the entopterygoid in the new material is normal and not expanded while that of P. qaidamensis is obviously expanded; and (2) the premaxilla process of maxilla is well developed in P. qaidamensis but weak in the new specimens. Therefore, they are described as a new species of the fossil genus Paleoschizothorax (subfamily Schizothoracinae): Paleoschizothorax diluculum sp. nov. A phylogenetic analysis, which included 13 extant genera and three fossil forms of barbines and schizothoracines and 70 morphological characters, also supports the close relationship between P. diluculum and primitive schizothoracines. A preliminary correlation analysis suggests that the degree of reduction of body scale size is negatively correlated with habitat mean temperatures among most Chinese cyprinids. Moreover, we speculate that the ‘primitive schizothoracines’ likely originated in the north-eastern–central Tibetan Plateau based on the fossil records and molecular phylogeny of the extant taxa. http://zoobank.org/urn:lsid:zoobank.org:pub:C461C7C0-9BAB-44DD-8DEE-0B5BB03D6479
{"title":"A new cyprinid from the Oligocene of Qaidam Basin, north-eastern Tibetan plateau, and its implications","authors":"Tao Yang, Weiyu Liang, Jiahao Cai, H. Gu, Lei Han, Hongyu Chen, Haojian Wang, Lin Bao, De-Fei Yan","doi":"10.1080/14772019.2021.2015470","DOIUrl":"https://doi.org/10.1080/14772019.2021.2015470","url":null,"abstract":"The Qaidam Basin, lying in the north-eastern Tibetan Plateau, China, is key to understanding the Cenozoic climatic and biological changes that have occurred on the plateau; however, information from a palaeontological perspective on this Palaeogene basin is scant. Recently, fossil cyprinids were found in the middle portion of the Shangganchaigou Formation (= Upper Ganchaigou Formation; Oligocene) in the north-western Qaidam Basin. These share many osteological characters with barbines and ‘morphologically primitive clade schizothoracines’ (= primitive schizothoracines; i.e. Schizothorax and Aspiorhynchus), and they closely resemble the latter in the size and shape of the scales: body scales are small and oval; the number of lateral line scales exceeds 100; and the long-oval scales from the pre-anal region are very similar to the ‘anal scales’, which are unique to schizothoracines. Compared with another fossil fish, Paleoschizothorax qaidamensis, from the same formation, the major differences are: (1) the posterior part of the entopterygoid in the new material is normal and not expanded while that of P. qaidamensis is obviously expanded; and (2) the premaxilla process of maxilla is well developed in P. qaidamensis but weak in the new specimens. Therefore, they are described as a new species of the fossil genus Paleoschizothorax (subfamily Schizothoracinae): Paleoschizothorax diluculum sp. nov. A phylogenetic analysis, which included 13 extant genera and three fossil forms of barbines and schizothoracines and 70 morphological characters, also supports the close relationship between P. diluculum and primitive schizothoracines. A preliminary correlation analysis suggests that the degree of reduction of body scale size is negatively correlated with habitat mean temperatures among most Chinese cyprinids. Moreover, we speculate that the ‘primitive schizothoracines’ likely originated in the north-eastern–central Tibetan Plateau based on the fossil records and molecular phylogeny of the extant taxa. http://zoobank.org/urn:lsid:zoobank.org:pub:C461C7C0-9BAB-44DD-8DEE-0B5BB03D6479","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1161 - 1182"},"PeriodicalIF":2.6,"publicationDate":"2021-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49189749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-02DOI: 10.1080/14772019.2021.2020917
S. Rozadilla, Federico Brissón-Egli, F. Agnolín, A. Aranciaga-Rolando, F. Novas
Here we describe a new hadrosaurid from the Upper Cretaceous (Campanian–Maastrichtian) Allen Formation of Río Negro Province, north-west Patagonia. The new taxon is based on cranial and postcranial elements from subadult and adult specimens. The new taxon may have reached 8–9 m in total body length, and it is diagnosed by a unique combination of characters, including a very low maxilla with respect to the dentary, and a dentary with a prominent and elongate anterior process with a deep groove on its anterior end, among other features. The new taxon is known from well-preserved elements and constitutes one of the most complete hadrosaurids known from South America. Features of the teeth, cranial and postcranial bones of the new taxon overlap with those of other hadrosaurid specimens previously recorded from this continent. This new evidence allows us to recognize that Secernosaurus koerneri, Bonapartesaurus rionegrensis and ‘Kritosaurus’ australis are valid taxa. The latter can be distinguished from the other South American taxa, as well as from Kritosaurus from North America. Thus, a new generic name is proposed for the species ‘Kritosaurus’ australis. Phylogenetic analysis recovers a new clade of South American hadrosaurids composed of the new taxon, ‘Kritosaurus’ australis, Bonapartesaurus and Secernosaurus. The new South American clade is tentatively nested among Kritosaurini and is supported by several traits, including an ilium with a subhorizontal ridge separating the preacetabular notch from the pubic pedicle, a longitudinal ridge on the dorsal surface of the postacetabular process, and a twisted distal end of the postacetabular process. The recovery of a monophyletic clade of South American hadrosaurids indicates that the history of the clade on Gondwanan landmasses is far from well understood, and new discoveries may change the current picture of the taxonomy and phylogenetic relationships of southern duck-billed dinosaurs. http://zoobank.org/urn:lsid:zoobank.org:pub:6C6F0056-9D3A-4097-A10E-2E33C9DB76B9
{"title":"A new hadrosaurid (Dinosauria: Ornithischia) from the Late Cretaceous of northern Patagonia and the radiation of South American hadrosaurids","authors":"S. Rozadilla, Federico Brissón-Egli, F. Agnolín, A. Aranciaga-Rolando, F. Novas","doi":"10.1080/14772019.2021.2020917","DOIUrl":"https://doi.org/10.1080/14772019.2021.2020917","url":null,"abstract":"Here we describe a new hadrosaurid from the Upper Cretaceous (Campanian–Maastrichtian) Allen Formation of Río Negro Province, north-west Patagonia. The new taxon is based on cranial and postcranial elements from subadult and adult specimens. The new taxon may have reached 8–9 m in total body length, and it is diagnosed by a unique combination of characters, including a very low maxilla with respect to the dentary, and a dentary with a prominent and elongate anterior process with a deep groove on its anterior end, among other features. The new taxon is known from well-preserved elements and constitutes one of the most complete hadrosaurids known from South America. Features of the teeth, cranial and postcranial bones of the new taxon overlap with those of other hadrosaurid specimens previously recorded from this continent. This new evidence allows us to recognize that Secernosaurus koerneri, Bonapartesaurus rionegrensis and ‘Kritosaurus’ australis are valid taxa. The latter can be distinguished from the other South American taxa, as well as from Kritosaurus from North America. Thus, a new generic name is proposed for the species ‘Kritosaurus’ australis. Phylogenetic analysis recovers a new clade of South American hadrosaurids composed of the new taxon, ‘Kritosaurus’ australis, Bonapartesaurus and Secernosaurus. The new South American clade is tentatively nested among Kritosaurini and is supported by several traits, including an ilium with a subhorizontal ridge separating the preacetabular notch from the pubic pedicle, a longitudinal ridge on the dorsal surface of the postacetabular process, and a twisted distal end of the postacetabular process. The recovery of a monophyletic clade of South American hadrosaurids indicates that the history of the clade on Gondwanan landmasses is far from well understood, and new discoveries may change the current picture of the taxonomy and phylogenetic relationships of southern duck-billed dinosaurs. http://zoobank.org/urn:lsid:zoobank.org:pub:6C6F0056-9D3A-4097-A10E-2E33C9DB76B9","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1207 - 1235"},"PeriodicalIF":2.6,"publicationDate":"2021-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47220742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-02DOI: 10.1080/14772019.2022.2032433
Emily E. Brown, R. Butler, P. Barrett, S. Maidment
The phylogenetic relationships of the species commonly referred to as ‘hypsilophodontids’ remain one of the key questions in ornithischian dinosaur research, having profound implications for understanding the origin, evolution and taxonomical compositions of several more recently evolved neornithischian clades. Recent phylogenetic analyses have recovered two conflicting placements for these taxa: (1) primarily within Cerapoda (Ornithopoda + Marginocephalia), as a paraphyletic assemblage of early ornithopods; and (2) primarily outside of Cerapoda, within the clade Thescelosauridae. Here we assess three recent independent neornithischian phylogenetic studies that have recovered topologies congruent with one of these placements. We compare the compositions of these data matrices and test how each of them responds to manipulation of taxa and characters. The positions in which controversial clades are recovered is shown to be highly dependent on the sample of taxa analysed; however, taxon incompleteness or instability is not a contributing factor in altering topology. Character completeness and homoplasy is shown not to significantly alter tree topology either, although these factors can affect resolution. In one matrix investigated, femoral and dental characters are found to provide disproportionate support for the placement of key taxa outside of Cerapoda, and the exclusion of a small number of these characters results in ‘hypsilophodontids’ falling within Ornithopoda. In contrast, matrices that originally recovered ‘hypsilophodontids’ within Cerapoda are comparably more stable, with this array of taxa remaining in a consistent position throughout all analyses. There is still much work to be done to resolve these relationships, but our study provides several suggestions for future analyses with the aim of resolving areas of conflict within the neornithischian tree.
{"title":"Assessing conflict between early neornithischian tree topologies","authors":"Emily E. Brown, R. Butler, P. Barrett, S. Maidment","doi":"10.1080/14772019.2022.2032433","DOIUrl":"https://doi.org/10.1080/14772019.2022.2032433","url":null,"abstract":"The phylogenetic relationships of the species commonly referred to as ‘hypsilophodontids’ remain one of the key questions in ornithischian dinosaur research, having profound implications for understanding the origin, evolution and taxonomical compositions of several more recently evolved neornithischian clades. Recent phylogenetic analyses have recovered two conflicting placements for these taxa: (1) primarily within Cerapoda (Ornithopoda + Marginocephalia), as a paraphyletic assemblage of early ornithopods; and (2) primarily outside of Cerapoda, within the clade Thescelosauridae. Here we assess three recent independent neornithischian phylogenetic studies that have recovered topologies congruent with one of these placements. We compare the compositions of these data matrices and test how each of them responds to manipulation of taxa and characters. The positions in which controversial clades are recovered is shown to be highly dependent on the sample of taxa analysed; however, taxon incompleteness or instability is not a contributing factor in altering topology. Character completeness and homoplasy is shown not to significantly alter tree topology either, although these factors can affect resolution. In one matrix investigated, femoral and dental characters are found to provide disproportionate support for the placement of key taxa outside of Cerapoda, and the exclusion of a small number of these characters results in ‘hypsilophodontids’ falling within Ornithopoda. In contrast, matrices that originally recovered ‘hypsilophodontids’ within Cerapoda are comparably more stable, with this array of taxa remaining in a consistent position throughout all analyses. There is still much work to be done to resolve these relationships, but our study provides several suggestions for future analyses with the aim of resolving areas of conflict within the neornithischian tree.","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1183 - 1206"},"PeriodicalIF":2.6,"publicationDate":"2021-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47340636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-18DOI: 10.1080/14772019.2021.2017363
M. Bisconti, Diana Ochoa, M. Urbina, R. Salas-Gismondi
Archaebalaenoptera eusebioi is a new late Miocene (Tortonian) balaenopterid species from the Aguada de Lomas locality in the Pisco Formation, Peru. It is dated to 8.85–7.93 Ma and is represented by a nearly complete skull with cervical vertebrae. Its inferred body length and mass are respectively c. 7 m and 7–11 tonnes. Archaebalaenoptera eusebioi is characterized by a short and wide rostrum, outward bowed dentary with typical balaenopterid characters in the posterior portion (posteriorly faced articular surface of the mandibular condyle, comparatively long distance between condyle and coronoid process, vestigial postcoronoid crest and fossa) and wide temporal fossa with scarcely protruding temporal crest and posteriorly placed posterior apex of nuchal crest. Its morphology suggests that it fed similarly to the modern balaenopterid whales but with a comparatively wider gape and, possibly, with a limited number of ventral throat grooves. Palaeobiogeographical analysis shows that Archaebalaenoptera originated in the North Atlantic and the invasion of South Pacific and Mediterranean occurred by subsequent dispersal events. Our results suggest that the North Atlantic acted as a centre of origin for many balaenopterid radiations and as a starting basin for recurrent invasions of other oceanic basins.
eusebioi古斑蝶是秘鲁皮斯科组Aguada de Lomas地区中新世晚期（Tortonian）的一种新斑蝶。日期为8.85–7.93 马，以一个几乎完整的带有颈椎的头骨为代表。其推测的身体长度和质量分别为约7米和7-11吨。欧氏始祖蝶的特征是喙短而宽，后部（下颌髁关节面朝后，髁突与冠状突之间距离较长，冠状嵴后嵴和窝残留）有典型的外翻齿状物，颞窝较宽，颞嵴几乎不突出，颈嵴后顶点位于后方。它的形态表明，它的进食方式与现代平衡头鲸相似，但有着相对较宽的间隙，可能还有数量有限的腹侧喉沟。古生物地理学分析表明，古翅目起源于北大西洋，南太平洋和地中海的入侵是由随后的扩散事件引起的。我们的研究结果表明，北大西洋是许多均衡辐射的起源中心，也是其他海盆反复入侵的起始盆地。
{"title":"Archaebalaenoptera eusebioi, a new rorqual from the late Miocene of Peru (Cetacea, Mysticeti, Balaenopteridae) and its impact in reconstructing body size evolution, ecomorphology and palaeobiogeography of Balaenopteridae","authors":"M. Bisconti, Diana Ochoa, M. Urbina, R. Salas-Gismondi","doi":"10.1080/14772019.2021.2017363","DOIUrl":"https://doi.org/10.1080/14772019.2021.2017363","url":null,"abstract":"Archaebalaenoptera eusebioi is a new late Miocene (Tortonian) balaenopterid species from the Aguada de Lomas locality in the Pisco Formation, Peru. It is dated to 8.85–7.93 Ma and is represented by a nearly complete skull with cervical vertebrae. Its inferred body length and mass are respectively c. 7 m and 7–11 tonnes. Archaebalaenoptera eusebioi is characterized by a short and wide rostrum, outward bowed dentary with typical balaenopterid characters in the posterior portion (posteriorly faced articular surface of the mandibular condyle, comparatively long distance between condyle and coronoid process, vestigial postcoronoid crest and fossa) and wide temporal fossa with scarcely protruding temporal crest and posteriorly placed posterior apex of nuchal crest. Its morphology suggests that it fed similarly to the modern balaenopterid whales but with a comparatively wider gape and, possibly, with a limited number of ventral throat grooves. Palaeobiogeographical analysis shows that Archaebalaenoptera originated in the North Atlantic and the invasion of South Pacific and Mediterranean occurred by subsequent dispersal events. Our results suggest that the North Atlantic acted as a centre of origin for many balaenopterid radiations and as a starting basin for recurrent invasions of other oceanic basins.","PeriodicalId":50028,"journal":{"name":"Journal of Systematic Palaeontology","volume":"19 1","pages":"1129 - 1160"},"PeriodicalIF":2.6,"publicationDate":"2021-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49589954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：