Pub Date : 2024-09-18DOI: 10.1186/s13358-024-00331-8
Li-Ang Gu, Andrzej S. Wolniewicz, Jun Liu
Chaohusaurus is an early ichthyosauriform represented by three species known from the Early Triassic of Chaohu, Anhui Province, China, with a fourth species—Chaohusaurus zhangjiawanensis—known from the Nanzhang-Yuan’an region of Hubei Province. In contrast to the Chaohusaurus species from Chaohu, Chaohusaurus zhangjiawanensis remains poorly known, hindering our understanding of early ichthyosauriform evolution. Here, we report a new specimen of Chaohusaurus zhangjiawanensis, which provides new information on its dentition. The new specimen confirms that Chaohusaurus zhangjiawanensis had heterodont dentition consisting of pointed anterior teeth and robust, rounded posterior teeth, indicating a generalist diet. The posterior teeth of Chaohusaurus zhangjiawanensis are more robust (broader and larger) than the posterior dentition of Chaohusaurus chaoxianensis and Chaohusaurus brevifemoralis from Chaohu. This suggests differences in hard-shelled prey preference between species of Chaohusaurus from Chaohu and Nanzhang-Yuan’an, with Chaohusaurus zhangjiawanensis likely capable of feeding on harder and larger prey than Chaohusaurus brevifemoralis and Chaohusaurus chaoxianensis. In turn, this probably reflects differences in durophagous prey availability between the shallow-marine palaeoecosystem of Nanzhang-Yuan’an and the deeper, slope-basin palaeoecosystem of Chaohu. The posterior dentition and forefin of Chaohusaurus zhangjiawanensis are strikingly similar to those of Chaohusaurus geishanensis, the rarest species of Chaohusaurus from the Chaohu fauna. The scarcity of Chaohusaurus geishanensis in the Chaohu fauna, and its morphological similarity to Chaohusaurus zhangjiawanensis, possibly indicate that Chaohusaurus geishanensis was closely related with Chaohusaurus zhangjiawanensis and that it was also a shallow-marine species that was not a typical component of the Chaohu fauna. It probably occasionally wandered out into the deeper waters of Chaohu from a nearby coastal environment.
{"title":"New information on the dentition of Chaohusaurus zhangjiawanensis (Reptilia, Ichthyosauriformes) from the Early Triassic of Yuan’an, Hubei Province, China","authors":"Li-Ang Gu, Andrzej S. Wolniewicz, Jun Liu","doi":"10.1186/s13358-024-00331-8","DOIUrl":"https://doi.org/10.1186/s13358-024-00331-8","url":null,"abstract":"Chaohusaurus is an early ichthyosauriform represented by three species known from the Early Triassic of Chaohu, Anhui Province, China, with a fourth species—Chaohusaurus zhangjiawanensis—known from the Nanzhang-Yuan’an region of Hubei Province. In contrast to the Chaohusaurus species from Chaohu, Chaohusaurus zhangjiawanensis remains poorly known, hindering our understanding of early ichthyosauriform evolution. Here, we report a new specimen of Chaohusaurus zhangjiawanensis, which provides new information on its dentition. The new specimen confirms that Chaohusaurus zhangjiawanensis had heterodont dentition consisting of pointed anterior teeth and robust, rounded posterior teeth, indicating a generalist diet. The posterior teeth of Chaohusaurus zhangjiawanensis are more robust (broader and larger) than the posterior dentition of Chaohusaurus chaoxianensis and Chaohusaurus brevifemoralis from Chaohu. This suggests differences in hard-shelled prey preference between species of Chaohusaurus from Chaohu and Nanzhang-Yuan’an, with Chaohusaurus zhangjiawanensis likely capable of feeding on harder and larger prey than Chaohusaurus brevifemoralis and Chaohusaurus chaoxianensis. In turn, this probably reflects differences in durophagous prey availability between the shallow-marine palaeoecosystem of Nanzhang-Yuan’an and the deeper, slope-basin palaeoecosystem of Chaohu. The posterior dentition and forefin of Chaohusaurus zhangjiawanensis are strikingly similar to those of Chaohusaurus geishanensis, the rarest species of Chaohusaurus from the Chaohu fauna. The scarcity of Chaohusaurus geishanensis in the Chaohu fauna, and its morphological similarity to Chaohusaurus zhangjiawanensis, possibly indicate that Chaohusaurus geishanensis was closely related with Chaohusaurus zhangjiawanensis and that it was also a shallow-marine species that was not a typical component of the Chaohu fauna. It probably occasionally wandered out into the deeper waters of Chaohu from a nearby coastal environment.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"29 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142260546","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 : 2024-09-16DOI: 10.1186/s13358-024-00332-7
Georgios L. Georgalis, Andrea Villa, Martin Ivanov, Massimo Delfino
We here describe abundant new fossil material of amphibians and reptiles from different late Neogene localities of northern Greece: the Early Pliocene (MN 14) of Spilia 0, Spilia 1, and Spilia 2; the Early Pliocene (MN 15) of Spilia 3, Spilia 4, Spilia 5, and Vevi; and the Late Miocene or Pliocene of Chalicorrema and Rema Marmara. These new late Neogene herpetofaunas are highly diverse, documenting a considerably rich herpetofauna allowing the identification of at least two salamander, seven frog, two turtle, seven lizard, and eight snake taxa. Salamanders are represented by the salamandrid genera Ommatotriton and Ichthyosaura. Frogs are represented by the bombinatorid Bombina, the discoglossids Latonia cf. ragei and Latonia sp., the pelobatid Pelobates aff. praefuscus and Pelobates sp., the ranids Pelophylax and Rana cf. dalmatina, the hylid Hyla gr. arborea, and the bufonid Bufotes gr. viridis. Turtles are represented by the emydid Emys and an indeterminate geoemydid. Lizards are represented by the scincid Ophiomorus, two lacertids (one of which potentially pertaining to Lacerta), amphisbaenians, agamids, the anguid Pseudopus, and a potential varanid. Snakes are represented by the erycid Eryx, the natricid Natrix aff. rudabanyaensis, a small-sized elapid, an “Oriental viper”, the colubriforms Periergophis and Paraxenophis, as well as two further distinct but still indeterminate morphotypes of colubriforms. For the material from Spilia tentatively referred to Ommatotriton, this is only the third occurrence in the fossil record globally. The new material of Ichthyosaura and Bombina mark the first documentation of these genera in the Greek fossil record. Abundant cranial and postcranial material from Spilia is tentatively referred to Latonia ragei, a taxon previously known from the Early Miocene of Western Europe. The new record of Pelobates represents the oldest documented occurrences of the genus in the Greek fossil record. Interestingly, the Pelobates from Spilia bears much resemblance to an extinct taxon, Pelobates aff. praefuscus, which is otherwise known from the Late Miocene of the Caucasus, and not to the extant species that currently inhabits the area. The identification of Pelophylax and Rana adds to the rather poor Neogene record of ranids from Greece. Particularly for the case of Rana cf. dalmatina from Spilia 4, this corresponds to the only documented occurrence of this extant taxon in the Greek fossil record. Similarly, the identification of Hyla gr. arborea in Spilia 1, Spilia 3, and Spilia 4, marks only the third documented occurrence of this genus in the Greek fossil record. The Bufotes material from Spilia 1, Spilia 3, and Spilia 4 represents the first documented fossil occurrence of the extant Bufotes viridis complex in Greece. The material of Emys gr. orbicularis from Vevi marks the only known pre-Quaternary record of the genus in Greece and one of the only few Neogene members of the genus known from Europe. The scincid Ophiomo
{"title":"New diverse amphibian and reptile assemblages from the late Neogene of northern Greece provide novel insights into the emergence of extant herpetofaunas of the southern Balkans","authors":"Georgios L. Georgalis, Andrea Villa, Martin Ivanov, Massimo Delfino","doi":"10.1186/s13358-024-00332-7","DOIUrl":"https://doi.org/10.1186/s13358-024-00332-7","url":null,"abstract":"We here describe abundant new fossil material of amphibians and reptiles from different late Neogene localities of northern Greece: the Early Pliocene (MN 14) of Spilia 0, Spilia 1, and Spilia 2; the Early Pliocene (MN 15) of Spilia 3, Spilia 4, Spilia 5, and Vevi; and the Late Miocene or Pliocene of Chalicorrema and Rema Marmara. These new late Neogene herpetofaunas are highly diverse, documenting a considerably rich herpetofauna allowing the identification of at least two salamander, seven frog, two turtle, seven lizard, and eight snake taxa. Salamanders are represented by the salamandrid genera Ommatotriton and Ichthyosaura. Frogs are represented by the bombinatorid Bombina, the discoglossids Latonia cf. ragei and Latonia sp., the pelobatid Pelobates aff. praefuscus and Pelobates sp., the ranids Pelophylax and Rana cf. dalmatina, the hylid Hyla gr. arborea, and the bufonid Bufotes gr. viridis. Turtles are represented by the emydid Emys and an indeterminate geoemydid. Lizards are represented by the scincid Ophiomorus, two lacertids (one of which potentially pertaining to Lacerta), amphisbaenians, agamids, the anguid Pseudopus, and a potential varanid. Snakes are represented by the erycid Eryx, the natricid Natrix aff. rudabanyaensis, a small-sized elapid, an “Oriental viper”, the colubriforms Periergophis and Paraxenophis, as well as two further distinct but still indeterminate morphotypes of colubriforms. For the material from Spilia tentatively referred to Ommatotriton, this is only the third occurrence in the fossil record globally. The new material of Ichthyosaura and Bombina mark the first documentation of these genera in the Greek fossil record. Abundant cranial and postcranial material from Spilia is tentatively referred to Latonia ragei, a taxon previously known from the Early Miocene of Western Europe. The new record of Pelobates represents the oldest documented occurrences of the genus in the Greek fossil record. Interestingly, the Pelobates from Spilia bears much resemblance to an extinct taxon, Pelobates aff. praefuscus, which is otherwise known from the Late Miocene of the Caucasus, and not to the extant species that currently inhabits the area. The identification of Pelophylax and Rana adds to the rather poor Neogene record of ranids from Greece. Particularly for the case of Rana cf. dalmatina from Spilia 4, this corresponds to the only documented occurrence of this extant taxon in the Greek fossil record. Similarly, the identification of Hyla gr. arborea in Spilia 1, Spilia 3, and Spilia 4, marks only the third documented occurrence of this genus in the Greek fossil record. The Bufotes material from Spilia 1, Spilia 3, and Spilia 4 represents the first documented fossil occurrence of the extant Bufotes viridis complex in Greece. The material of Emys gr. orbicularis from Vevi marks the only known pre-Quaternary record of the genus in Greece and one of the only few Neogene members of the genus known from Europe. The scincid Ophiomo","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"99 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142260642","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 : 2024-09-11DOI: 10.1186/s13358-024-00329-2
Jozef Klembara, Marcello Ruta, Jason Anderson, Taran Mayer, Miroslav Hain, Daniel Valaška
The Upper Carboniferous protorothyridid amniote Brouffia orientalis from Czech Republic is redescribed. Photogrammetric scanning of the holotype and only known specimen yields considerable new information on the skull and postcranium of this tetrapod and allows us to amend previous morphological descriptions to a substantial degree. A virtual 3D model built from photogrammetry scan data is used as the basis for a new reconstruction of the skull in dorsal, lateral, and ventral aspects and the lower jaw in lateral aspect. We expand and refine the diagnosis of Brouffia and compare it with other protorothyridids. We discuss the affinities of this taxon by coding it in a recently published data matrix of early amniotes, which we subject to maximum parsimony and Bayesian fossilized birth–death analyses. Brouffia emerges as the sister taxon to Coelostegus in all analyses, but the position of these two taxa within amniotes varies. In a parsimony analysis with unweighted characters, the (Brouffia + Coelostegus) clade forms the sister group to Synapsida. In various experiments of character reweighting, that clade is placed crownward of Captorhinidae on the stem-group of Reptilia, but anticrownward of remaining protorothyridids. The latter constitute either a paraphyletic array relative to Diapsida or their monophyletic sister group. The Bayesian analysis retrieves (Brouffia + Coelostegus) as the most basal plesion on the stem-group of Reptilia.
{"title":"A redescription of Brouffia orientalis Carroll & Baird, 1972 from the Upper Carboniferous of the Czech Republic and the status and affinities of protorothyridid amniotes","authors":"Jozef Klembara, Marcello Ruta, Jason Anderson, Taran Mayer, Miroslav Hain, Daniel Valaška","doi":"10.1186/s13358-024-00329-2","DOIUrl":"https://doi.org/10.1186/s13358-024-00329-2","url":null,"abstract":"The Upper Carboniferous protorothyridid amniote Brouffia orientalis from Czech Republic is redescribed. Photogrammetric scanning of the holotype and only known specimen yields considerable new information on the skull and postcranium of this tetrapod and allows us to amend previous morphological descriptions to a substantial degree. A virtual 3D model built from photogrammetry scan data is used as the basis for a new reconstruction of the skull in dorsal, lateral, and ventral aspects and the lower jaw in lateral aspect. We expand and refine the diagnosis of Brouffia and compare it with other protorothyridids. We discuss the affinities of this taxon by coding it in a recently published data matrix of early amniotes, which we subject to maximum parsimony and Bayesian fossilized birth–death analyses. Brouffia emerges as the sister taxon to Coelostegus in all analyses, but the position of these two taxa within amniotes varies. In a parsimony analysis with unweighted characters, the (Brouffia + Coelostegus) clade forms the sister group to Synapsida. In various experiments of character reweighting, that clade is placed crownward of Captorhinidae on the stem-group of Reptilia, but anticrownward of remaining protorothyridids. The latter constitute either a paraphyletic array relative to Diapsida or their monophyletic sister group. The Bayesian analysis retrieves (Brouffia + Coelostegus) as the most basal plesion on the stem-group of Reptilia.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"15 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177244","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 : 2024-09-10DOI: 10.1186/s13358-024-00330-9
Gabriele Bindellini, Andrzej S. Wolniewicz, Feiko Miedema, Cristiano Dal Sasso, Torsten M. Scheyer
Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996 was originally described on the basis of a single complete fossil specimen excavated near Besano (Italy). However, a recent taxonomic revision and re-examination of the cranial osteology allowed for the assignment of five additional specimens to the taxon. Here, we analyse, describe and discuss the postcranial anatomy of Besanosaurus leptorhynchus in detail. The size of the specimens examined herein ranged from slightly more than one meter to eight meters. Overall, several diagnostic character states for this taxon are proposed, demonstrating a mosaic of plesiomorphic and derived features. This is best exemplified by the limbs, which show very rounded elements in the forelimbs, and pedal phalanges with retained rudimentary shafts. We suggest that the widely spaced phalanges in the forefins of Besanosaurus leptorhynchus were embedded in a fibrocartilage-rich connective tissue, like in modern cetaceans. We also review the similarities of Besanosaurus with Pessopteryx and Pessosaurus, allowing us to conclude that Besanosaurus is not a junior synonym of either of the two taxa. Lastly, to test the swimming capabilities of Besanosaurus leptorhynchus, we expanded on a previously published study focussing on reconstructing the swimming styles of ichthyosaurs. Besanosaurus leptorhynchus was found to possess a peculiar locomotory mode, somewhat intermediate between anguilliform swimmers, such as Cymbospondylus and Utatsusaurus, and some shastasaur-grade (e.g., Guizhouichthyosaurus) and early-diverging euichthyosaurian (e.g., Californosaurus) ichthyosaurs. Based on our results, we furthermore suggest that mixosaurids acquired their characteristic body profile (dorsal fin and forefins that are distinctly enlarged compared to the hindfins) independently and convergently to the one that later appeared in Parvipelvia. Moreover, the different swimming styles inferred for Cymbospondylus, Mixosauridae, and Besanosaurus strengthen the earlier hypothesis of niche partitioning among these three distinct ichthyosaur taxa from the Besano Formation.
Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996最初是根据在贝萨诺(意大利)附近发掘的一个完整化石标本描述的。然而,最近的分类学修订和头盖骨学的重新研究使得该分类群又多了五个标本。在这里,我们详细分析、描述并讨论了贝萨龙的颅后解剖结构。本文所研究的标本大小从一米多一点到八米不等。总体而言,本文提出了该类群的几种诊断特征状态,展示了多同形和衍生特征的组合。最典型的例子是四肢,前肢显示出非常圆润的元素,脚趾趾骨保留着不成熟的轴。我们认为,贝沙龙前鳍的趾骨间距较大,嵌入了富含纤维软骨的结缔组织,就像现代鲸类动物一样。我们还回顾了贝散龙与栉龙和栉龙的相似之处,从而得出结论:贝散龙不是这两个类群中任何一个类群的小异名。最后,为了检验贝萨龙的游泳能力,我们对之前发表的一项研究进行了扩展,该研究的重点是重建鱼龙的游泳方式。研究发现,贝萨龙具有一种奇特的运动模式,介于鲶形游泳者(如鲤形龙和乌塔斯龙)和一些刹龙类(如贵州鱼龙)以及早期分化的鱼龙类(如加利福尼亚龙)之间。基于我们的研究结果,我们进一步提出,混合龙类获得其特征性身体轮廓(背鳍和前鳍与后鳍相比明显增大)是独立的,并与后来出现在副鱼龙类的身体轮廓趋同。此外,推断出的栉龙科、混龙科和贝散龙的不同游泳方式加强了早先关于贝萨诺地层中这三个不同鱼龙类群之间生态位分区的假说。
{"title":"Postcranial anatomy of Besanosaurus leptorhynchus (Reptilia: Ichthyosauria) from the Middle Triassic Besano Formation of Monte San Giorgio (Italy/Switzerland), with implications for reconstructing the swimming styles of Triassic ichthyosaurs","authors":"Gabriele Bindellini, Andrzej S. Wolniewicz, Feiko Miedema, Cristiano Dal Sasso, Torsten M. Scheyer","doi":"10.1186/s13358-024-00330-9","DOIUrl":"https://doi.org/10.1186/s13358-024-00330-9","url":null,"abstract":"Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996 was originally described on the basis of a single complete fossil specimen excavated near Besano (Italy). However, a recent taxonomic revision and re-examination of the cranial osteology allowed for the assignment of five additional specimens to the taxon. Here, we analyse, describe and discuss the postcranial anatomy of Besanosaurus leptorhynchus in detail. The size of the specimens examined herein ranged from slightly more than one meter to eight meters. Overall, several diagnostic character states for this taxon are proposed, demonstrating a mosaic of plesiomorphic and derived features. This is best exemplified by the limbs, which show very rounded elements in the forelimbs, and pedal phalanges with retained rudimentary shafts. We suggest that the widely spaced phalanges in the forefins of Besanosaurus leptorhynchus were embedded in a fibrocartilage-rich connective tissue, like in modern cetaceans. We also review the similarities of Besanosaurus with Pessopteryx and Pessosaurus, allowing us to conclude that Besanosaurus is not a junior synonym of either of the two taxa. Lastly, to test the swimming capabilities of Besanosaurus leptorhynchus, we expanded on a previously published study focussing on reconstructing the swimming styles of ichthyosaurs. Besanosaurus leptorhynchus was found to possess a peculiar locomotory mode, somewhat intermediate between anguilliform swimmers, such as Cymbospondylus and Utatsusaurus, and some shastasaur-grade (e.g., Guizhouichthyosaurus) and early-diverging euichthyosaurian (e.g., Californosaurus) ichthyosaurs. Based on our results, we furthermore suggest that mixosaurids acquired their characteristic body profile (dorsal fin and forefins that are distinctly enlarged compared to the hindfins) independently and convergently to the one that later appeared in Parvipelvia. Moreover, the different swimming styles inferred for Cymbospondylus, Mixosauridae, and Besanosaurus strengthen the earlier hypothesis of niche partitioning among these three distinct ichthyosaur taxa from the Besano Formation.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"34 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177246","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 : 2024-08-19DOI: 10.1186/s13358-024-00325-6
Adriana López-Arbarello, Rainer Brocke
Our new study of the species originally included in the genus Allolepidotus led to the taxonomic revision of the halecomorph species from the Triassic of Perledo, Italy. The morphological variation revealed by the analysis of the type material is sufficient to confirm four different taxa represented in the Perledo Formation. We correct the misunderstanding about the type species of Allolepidotus, which is A. ruppelii and not “A.” bellottii as considered in the literature over the past two decades. The latter species was originally placed in the genus Semionotus. Fossils from the Kalkschieferzone of Besnasca/Ca' del Frate (Viggiù-Varese, Italy) and Meride (Ticino, Switzerland) which were referred to Allolepidotus, rather represent a species of Eoeugnathus. Therefore, we transfer the species Semionotus bellottii to that genus and propose the new combination E. bellottii. The second and only other species originally included in the genus Allolepidotus is transferred here to the new genus Perledovatus. The holotype of P. nothosomoides new comb. has been mechanically prepared, revealing additional anatomical information that allows to place this taxon in the halecomorph family Subortichthyidae. The other halecomorph species named from the Perledo Formation, Pholidophorus oblongus and Pholidophorus curionii, have been treated as junior synonyms of E. bellottii, but our analysis indicates that they represent distinct separate taxa. However, due to the loss of the type specimens, it is not possible to decide whether they might have been conspecific with other ray-finned fishes from the Middle Triassic of the Alps.
我们对最初被归入Allolepidotus属的物种进行了新的研究,从而对意大利佩雷多三叠纪的卤虫物种进行了分类学修订。对模式材料的分析所揭示的形态变异足以确认佩雷多地层中有四个不同的类群。我们纠正了对 Allolepidotus 模式种的误解,它是 A. ruppelii,而不是过去二十年来文献中认为的 "A." bellottii。后者最初被归入 Semionotus 属。来自 Besnasca/Ca' del Frate(意大利 Viggiù-Varese)和 Meride(瑞士提契诺州)的 Kalkschieferzone 的化石被认为是 Allolepidotus,而代表了 Eoeugnathus 的一个物种。因此,我们将 Semionotus bellottii 转到该属,并提出新的组合 E. bellottii。原属 Allolepidotus 的第二个,也是唯一的一个物种,在此转入新属 Perledovatus。P. nothosomoides new comb.的主模式是机械制备的,揭示了更多的解剖学信息,从而可以将该分类群归入半知母鱼科(Subortichthyidae)。在 Perledo Formation 发现的其他半拟态鱼类,Pholidophorus oblongus 和 Pholidophorus curionii,一直被视为 E. bellottii 的初级异名,但我们的分析表明,它们是不同的独立类群。然而,由于模式标本的丢失,我们无法确定它们是否可能与阿尔卑斯山中三叠世的其他鳐形鳍鱼类同属。
{"title":"New generic name for a small Triassic ray-finned fish from Perledo (Italy)","authors":"Adriana López-Arbarello, Rainer Brocke","doi":"10.1186/s13358-024-00325-6","DOIUrl":"https://doi.org/10.1186/s13358-024-00325-6","url":null,"abstract":"Our new study of the species originally included in the genus Allolepidotus led to the taxonomic revision of the halecomorph species from the Triassic of Perledo, Italy. The morphological variation revealed by the analysis of the type material is sufficient to confirm four different taxa represented in the Perledo Formation. We correct the misunderstanding about the type species of Allolepidotus, which is A. ruppelii and not “A.” bellottii as considered in the literature over the past two decades. The latter species was originally placed in the genus Semionotus. Fossils from the Kalkschieferzone of Besnasca/Ca' del Frate (Viggiù-Varese, Italy) and Meride (Ticino, Switzerland) which were referred to Allolepidotus, rather represent a species of Eoeugnathus. Therefore, we transfer the species Semionotus bellottii to that genus and propose the new combination E. bellottii. The second and only other species originally included in the genus Allolepidotus is transferred here to the new genus Perledovatus. The holotype of P. nothosomoides new comb. has been mechanically prepared, revealing additional anatomical information that allows to place this taxon in the halecomorph family Subortichthyidae. The other halecomorph species named from the Perledo Formation, Pholidophorus oblongus and Pholidophorus curionii, have been treated as junior synonyms of E. bellottii, but our analysis indicates that they represent distinct separate taxa. However, due to the loss of the type specimens, it is not possible to decide whether they might have been conspecific with other ray-finned fishes from the Middle Triassic of the Alps.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"42 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177248","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 : 2024-07-30DOI: 10.1186/s13358-024-00322-9
María Victoria Paredes-Aliaga, Héctor Botella, Alejandro Romero
Dental microwear analysis is a well-established technique that provides valuable information about the diets of extant and extinct taxa. It has been used effectively in most major groups of vertebrates. However, in chondrichthyans, these methods have been implemented only recently in the form of dental microwear texture analysis, with conflicting results. Causes intrinsic to chondrichthyan biology, such as limited food-to-tooth contact, low diversity in terms of trophic categories or fast tooth replacement, have been suggested to reduce diet-related wear on individual teeth, hindering the use of this approach for reliable dietary reconstruction. Here, we explored the relationship between diet and dental microwear in chondrichthyans by using 2D analysis, which can provide finer-scale identification and accurate definition of scratch morphology from tooth surfaces a priori. Scratches were counted and measured on the teeth of 34 extant elasmobranchs grouped into three categories (piscivorous, durophagous and generalist) according to dietary preferences. Our results revealed specific patterns of tooth microwear as a function of dietary abrasiveness, enabling the discrimination of trophic groups and thus establishing a useful comparative framework for inferring aspects of trophic ecology in fossils. We then used this information to study dental microwear in six fossil species from the same locality and stratigraphic levels. First, analyses of the enameloid surfaces of the fossil show that post-mortem alterations are distinguishable, allowing reliable quantification of diet-related ante-mortem microwear signatures. Discriminant analysis allowed the recognition of microwear patterns comparable to those of living sharks and linked them to specific trophic groups with high probability levels (> 90%). Thus, microwear features developing on chondrichthyan teeth during feeding are intense enough to retain information regarding diet preferences. 2D microwear analysis can track this information, proving to be a useful tool for providing significant information not only about diet but also about oral processing mechanisms in extinct chondrichthyans.
{"title":"Testing dental microwear as a proxy for characterising trophic ecology in fossil elasmobranchs (chondrichthyans)","authors":"María Victoria Paredes-Aliaga, Héctor Botella, Alejandro Romero","doi":"10.1186/s13358-024-00322-9","DOIUrl":"https://doi.org/10.1186/s13358-024-00322-9","url":null,"abstract":"Dental microwear analysis is a well-established technique that provides valuable information about the diets of extant and extinct taxa. It has been used effectively in most major groups of vertebrates. However, in chondrichthyans, these methods have been implemented only recently in the form of dental microwear texture analysis, with conflicting results. Causes intrinsic to chondrichthyan biology, such as limited food-to-tooth contact, low diversity in terms of trophic categories or fast tooth replacement, have been suggested to reduce diet-related wear on individual teeth, hindering the use of this approach for reliable dietary reconstruction. Here, we explored the relationship between diet and dental microwear in chondrichthyans by using 2D analysis, which can provide finer-scale identification and accurate definition of scratch morphology from tooth surfaces a priori. Scratches were counted and measured on the teeth of 34 extant elasmobranchs grouped into three categories (piscivorous, durophagous and generalist) according to dietary preferences. Our results revealed specific patterns of tooth microwear as a function of dietary abrasiveness, enabling the discrimination of trophic groups and thus establishing a useful comparative framework for inferring aspects of trophic ecology in fossils. We then used this information to study dental microwear in six fossil species from the same locality and stratigraphic levels. First, analyses of the enameloid surfaces of the fossil show that post-mortem alterations are distinguishable, allowing reliable quantification of diet-related ante-mortem microwear signatures. Discriminant analysis allowed the recognition of microwear patterns comparable to those of living sharks and linked them to specific trophic groups with high probability levels (> 90%). Thus, microwear features developing on chondrichthyan teeth during feeding are intense enough to retain information regarding diet preferences. 2D microwear analysis can track this information, proving to be a useful tool for providing significant information not only about diet but also about oral processing mechanisms in extinct chondrichthyans.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"20 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141870498","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 : 2024-07-12DOI: 10.1186/s13358-024-00323-8
Juliette C. L. Menon, Donald B. Brinkman, Guilherme Hermanson, Walter G. Joyce, Serjoscha W. Evers
The early evolution of Pan-Chelonioidea (sea turtles) is poorly understood. This is in part due to the rarity of undeformed skulls of definitive early stem chelonioids. In this work, we redescribe the holotype of Nichollsemys baieri using µCT scans and segmentations of the skull. This fossil is the best 3D preserved skull of any Campanian sea turtle, and includes partial “soft tissue” preservation. Nichollsemys is morphologically similar but clearly distinct from Toxochelys spp., and both show a mosaic of plesiomorphic and derived chelonioid features. The internal cranial anatomy documents the presence of derived characters in Nichollsemys baieri that are absent in Toxochelys spp., such as the loss of the epipterygoids and the rod-like shape of the rostrum basisphenoidale. Among the numerous plesiomorphic characters is the presence of a splenial bone, which was unnoticed before. An updated phylogenetic analysis retrieves Nichollsemys baieri as a non-protostegid early stem chelonioid in a slightly more crownward position than Toxochelys latiremis. Our phylogeny includes macrobaenids and protostegids as pan-chelonioids, and we find unorthodox results for dermochelyids. Thus, although Nichollsemys baieri provides important new insights into the early morphological evolution of sea turtles, much work remains to be done. As a completely 3D preserved specimen, we included Nichollsemys baieri into a recent landmark-based skull shape dataset of turtles. Morphospace analysis reveals an intermediate position between cryptodires and crown chelonioids. Based on these data, we also predict that Nichollsemys baieri was still capable of neck retraction, constraining the loss of this trait to more crownward pan-chelonioids.
人们对海龟(Pan-Chelonioidea)的早期演化知之甚少。这部分是由于确定的早期干海龟类的未变形头骨非常罕见。在这项研究中,我们利用 µCT 扫描和头骨分割重新描述了 Nichollsemys baieri 的主模式。该化石是所有坎帕尼亚海龟中三维保存最好的头骨,包括部分 "软组织 "的保存。Nichollsemys 在形态上与 Toxochelys 类似,但又明显有别于 Toxochelys,两者都显示出多形性和衍生的螯足类特征。头颅内部解剖结构表明,Nichollsemys baieri 存在着 Toxochelys spp.所不具备的衍生特征,如上翼的缺失和喙基鼻的杆状形状。在众多同形特征中,脾骨的存在是以前从未注意到的。经过更新的系统发生分析,Nichollsemys baieri被认为是一种非原栉水母类的早期茎栉水母类,其位置比Toxochelys latiremis稍稍靠后。我们的系统发育包括了作为泛螯足类的大鳞螯足类和原螯足类,我们发现鳞螯足类的系统发育结果并不正统。因此,尽管 Nichollsemys baieri 为海龟的早期形态演化提供了重要的新见解,但仍有许多工作要做。作为一个完全三维保存的标本,我们将 Nichollsemys baieri 纳入了最近基于地标的海龟头骨形状数据集中。形态空间分析表明,Nichollsemys baieri介于隐翅类和冠螯类之间。基于这些数据,我们还预测 Nichollsemys baieri 仍然能够缩颈,从而限制了更多冠状泛长尾龟丧失这一特征的可能性。
{"title":"New insights into the early morphological evolution of sea turtles by re-investigation of Nichollsemys baieri, a three-dimensionally preserved fossil stem chelonioid from the Campanian of Alberta, Canada","authors":"Juliette C. L. Menon, Donald B. Brinkman, Guilherme Hermanson, Walter G. Joyce, Serjoscha W. Evers","doi":"10.1186/s13358-024-00323-8","DOIUrl":"https://doi.org/10.1186/s13358-024-00323-8","url":null,"abstract":"The early evolution of Pan-Chelonioidea (sea turtles) is poorly understood. This is in part due to the rarity of undeformed skulls of definitive early stem chelonioids. In this work, we redescribe the holotype of Nichollsemys baieri using µCT scans and segmentations of the skull. This fossil is the best 3D preserved skull of any Campanian sea turtle, and includes partial “soft tissue” preservation. Nichollsemys is morphologically similar but clearly distinct from Toxochelys spp., and both show a mosaic of plesiomorphic and derived chelonioid features. The internal cranial anatomy documents the presence of derived characters in Nichollsemys baieri that are absent in Toxochelys spp., such as the loss of the epipterygoids and the rod-like shape of the rostrum basisphenoidale. Among the numerous plesiomorphic characters is the presence of a splenial bone, which was unnoticed before. An updated phylogenetic analysis retrieves Nichollsemys baieri as a non-protostegid early stem chelonioid in a slightly more crownward position than Toxochelys latiremis. Our phylogeny includes macrobaenids and protostegids as pan-chelonioids, and we find unorthodox results for dermochelyids. Thus, although Nichollsemys baieri provides important new insights into the early morphological evolution of sea turtles, much work remains to be done. As a completely 3D preserved specimen, we included Nichollsemys baieri into a recent landmark-based skull shape dataset of turtles. Morphospace analysis reveals an intermediate position between cryptodires and crown chelonioids. Based on these data, we also predict that Nichollsemys baieri was still capable of neck retraction, constraining the loss of this trait to more crownward pan-chelonioids.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"32 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141613360","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 : 2024-07-10DOI: 10.1186/s13358-024-00324-7
Nora Corthésy, Farid Saleh, Camille Thomas, Jonathan B. Antcliffe, Allison C. Daley
Fossilization, or the transition of an organism from the biosphere to the geosphere, is a complex mechanism involving numerous biological and geological variables. Bacteria are one of the most significant biotic players to decompose organic matter in natural environments, early on during fossilization. However, bacterial processes are difficult to characterize as many different abiotic conditions can influence bacterial efficiency in degrading tissues. One potentially important variable is the composition and nature of the sediment on which a carcass is deposited after death. We experimentally examined this by decaying the marine shrimp Palaemon varians underwater on three different clay sediments. Samples were then analyzed using 16S ribosomal RNA sequencing to identify the bacterial communities associated with each clay system. Results show that samples decaying on the surface of kaolinite have a lower bacterial diversity than those decaying on the surface of bentonite and montmorillonite, which could explain the limited decay of carcasses deposited on this clay. However, this is not the only role played by kaolinite, as a greater proportion of gram-negative over gram-positive bacteria is observed in this system. Gram-positive bacteria are generally thought to be more efficient at recycling complex polysaccharides such as those forming the body walls of arthropods. This is the first experimental evidence of sediments shaping an entire bacterial community. Such interaction between sediments and bacteria might have contributed to arthropods’ exquisite preservation and prevalence in kaolinite-rich Lagerstätten of the Cambrian Explosion.
{"title":"The effects of clays on bacterial community composition during arthropod decay","authors":"Nora Corthésy, Farid Saleh, Camille Thomas, Jonathan B. Antcliffe, Allison C. Daley","doi":"10.1186/s13358-024-00324-7","DOIUrl":"https://doi.org/10.1186/s13358-024-00324-7","url":null,"abstract":"Fossilization, or the transition of an organism from the biosphere to the geosphere, is a complex mechanism involving numerous biological and geological variables. Bacteria are one of the most significant biotic players to decompose organic matter in natural environments, early on during fossilization. However, bacterial processes are difficult to characterize as many different abiotic conditions can influence bacterial efficiency in degrading tissues. One potentially important variable is the composition and nature of the sediment on which a carcass is deposited after death. We experimentally examined this by decaying the marine shrimp Palaemon varians underwater on three different clay sediments. Samples were then analyzed using 16S ribosomal RNA sequencing to identify the bacterial communities associated with each clay system. Results show that samples decaying on the surface of kaolinite have a lower bacterial diversity than those decaying on the surface of bentonite and montmorillonite, which could explain the limited decay of carcasses deposited on this clay. However, this is not the only role played by kaolinite, as a greater proportion of gram-negative over gram-positive bacteria is observed in this system. Gram-positive bacteria are generally thought to be more efficient at recycling complex polysaccharides such as those forming the body walls of arthropods. This is the first experimental evidence of sediments shaping an entire bacterial community. Such interaction between sediments and bacteria might have contributed to arthropods’ exquisite preservation and prevalence in kaolinite-rich Lagerstätten of the Cambrian Explosion.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"30 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572865","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 : 2024-05-30DOI: 10.1186/s13358-024-00320-x
Christian Klug, Günter Schweigert, René Hoffmann, Dirk Fuchs, Alexander Pohle, Robert Weis, Kenneth De Baets
Belemnite rostra are very abundant in Mesozoic marine deposits in many regions. Despite this abundance, soft-tissue specimens of belemnites informing about anatomy and proportions of these coleoid cephalopods are extremely rare and limited to a few moderately large genera like Passaloteuthis and Hibolithes. For all other genera, we can make inferences on their body proportions and body as well as mantle length by extrapolating from complete material. We collected data of the proportions of the hard parts of some Jurassic belemnites in order to learn about shared characteristics in their gross anatomy. This knowledge is then applied to the Bajocian genus Megateuthis, which is the largest known belemnite genus worldwide. Our results provide simple ratios that can be used to estimate belemnite body size, where only the rostrum is known.
{"title":"Anatomy and size of Megateuthis, the largest belemnite","authors":"Christian Klug, Günter Schweigert, René Hoffmann, Dirk Fuchs, Alexander Pohle, Robert Weis, Kenneth De Baets","doi":"10.1186/s13358-024-00320-x","DOIUrl":"https://doi.org/10.1186/s13358-024-00320-x","url":null,"abstract":"Belemnite rostra are very abundant in Mesozoic marine deposits in many regions. Despite this abundance, soft-tissue specimens of belemnites informing about anatomy and proportions of these coleoid cephalopods are extremely rare and limited to a few moderately large genera like Passaloteuthis and Hibolithes. For all other genera, we can make inferences on their body proportions and body as well as mantle length by extrapolating from complete material. We collected data of the proportions of the hard parts of some Jurassic belemnites in order to learn about shared characteristics in their gross anatomy. This knowledge is then applied to the Bajocian genus Megateuthis, which is the largest known belemnite genus worldwide. Our results provide simple ratios that can be used to estimate belemnite body size, where only the rostrum is known.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"2012 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141195744","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 : 2024-05-08DOI: 10.1186/s13358-024-00316-7
Martin Košťák, Ján Schlögl, Dirk Fuchs, Milan Havrila, Tea Kolar-Jurkovšek, Attila Vörös, Martina Havelcová, Juraj Šurka, Jakub Havrila, Katarína Holcová
Two stratigraphically well constrained (by ammonites and conodonts) coleoid remains have been recorded from the Triassic (Anisian) dark-grey organodetritic limestones (Ráztoka Limestone) of Western Carpathians (Hronic Nappe). The limestones deposited at the periphery of a former carbonate platform. It yields a highly diverse cephalopod fauna including nautiloids (2 taxa), ammonoids (7 taxa) and indetermined aulacoceratids. Two unusual coleoid specimens are referred to genus Mojsisovicsteuthis (M. boeckhi) and probably to a new taxon (described as Breviconoteuthis aff. breviconus herein) possessing similar morphological features of genus Breviconoteuthis (Phragmoteuthida) and/or Zugmontites. Based on index ammonites and conodonts, both records are of the uppermost Trinodosus through the lowermost Reitzi zones (Anisian—lower Illyrian). While the genus Mojsisovicsteuthis has been widely dispersed (however its records are rare), the occurrence of Breviconoteuthis and Zugmontites is strictly limited to the Alpine-Carpathian region. Comparing with the holotype and additional specimens stored in the Hungarian Natural History Museum, the overal shell of Mojsisovicsteuthis and its size has been reconstructed. Its relationship to aulacoceratids and phragmoteuthids is briefly discussed. Geochemical record (n-alkanes from the bulk rock) provided a relevant signal of the existence of algal meadows.
{"title":"Rare Middle Triassic coleoids from the Alpine-Carpathian system: new records from Slovakia and their significance","authors":"Martin Košťák, Ján Schlögl, Dirk Fuchs, Milan Havrila, Tea Kolar-Jurkovšek, Attila Vörös, Martina Havelcová, Juraj Šurka, Jakub Havrila, Katarína Holcová","doi":"10.1186/s13358-024-00316-7","DOIUrl":"https://doi.org/10.1186/s13358-024-00316-7","url":null,"abstract":"Two stratigraphically well constrained (by ammonites and conodonts) coleoid remains have been recorded from the Triassic (Anisian) dark-grey organodetritic limestones (Ráztoka Limestone) of Western Carpathians (Hronic Nappe). The limestones deposited at the periphery of a former carbonate platform. It yields a highly diverse cephalopod fauna including nautiloids (2 taxa), ammonoids (7 taxa) and indetermined aulacoceratids. Two unusual coleoid specimens are referred to genus Mojsisovicsteuthis (M. boeckhi) and probably to a new taxon (described as Breviconoteuthis aff. breviconus herein) possessing similar morphological features of genus Breviconoteuthis (Phragmoteuthida) and/or Zugmontites. Based on index ammonites and conodonts, both records are of the uppermost Trinodosus through the lowermost Reitzi zones (Anisian—lower Illyrian). While the genus Mojsisovicsteuthis has been widely dispersed (however its records are rare), the occurrence of Breviconoteuthis and Zugmontites is strictly limited to the Alpine-Carpathian region. Comparing with the holotype and additional specimens stored in the Hungarian Natural History Museum, the overal shell of Mojsisovicsteuthis and its size has been reconstructed. Its relationship to aulacoceratids and phragmoteuthids is briefly discussed. Geochemical record (n-alkanes from the bulk rock) provided a relevant signal of the existence of algal meadows.","PeriodicalId":56059,"journal":{"name":"Swiss Journal of Palaeontology","volume":"16 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140941771","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}