Papers in Palaeontology最新文献

{"title":"Radiolarian response to environmental changes at the Sinemurian–Pliensbachian transition in the Northern Calcareous Alps, Austria","authors":"Tim Cifer, Špela Goričan, Attila Demény, Hans‐Jürgen Gawlick","doi":"10.1002/spp2.1581","DOIUrl":"https://doi.org/10.1002/spp2.1581","url":null,"abstract":"Major environmental, climate and sealevel changes occurred in the Western Tethyan Realm during the late Sinemurian to early Pliensbachian time interval. Here, we examine how these changes affected the taxonomic composition of radiolarian fauna. Radiolarian assemblages were collected on Mount Rettenstein (Northern Calcareous Alps) from a siliceous limestone and marl succession, deposited in a well‐oxygenated basin a few hundred metres in depth on the continental shelf at the western edge of the Neotethys Ocean. Radiolarian research was complemented with elemental and isotope geochemistry on bulk carbonate samples. The siliceous microfaunas below and above the stage boundary consist of more than 80% sponge spicules and less than 20% radiolarians, with a strong predominance of the Order Spumellaria. The Nassellaria to Spumellaria abundance ratio ranges from 1:5 to 1:3. At the Sinemurian–Pliensbachian transition, a significant drop in diversity occurred, accompanied by a substantial change in relative abundances of radiolarian taxa. The most severely affected groups were surface‐dwelling radiolarians (Angulobrachiidae, Hagiastridae, Pantanelliidae; mostly <jats:italic>Gorgansium</jats:italic>, Poulpidae and Ultranaporidae), which almost or completely disappeared. In contrast, <jats:italic>Archaeocenosphaera</jats:italic>, <jats:italic>Praeconocaryomma</jats:italic>, <jats:italic>Zhamoidellum</jats:italic> and <jats:italic>Lantus</jats:italic> became abundant and were apparently the most resistant to environmental stress. The changes in radiolarian assemblages were local and probably induced by the end‐Sinemurian sealevel drop that transformed the area into a semi‐enclosed basin with restricted ocean circulation. The exchange of water masses and thus radiolarian faunas with the open sea was reduced and their productivity may have been lowered by the lower inflow of fertile waters from the ocean.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141769676","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}

{"title":"The rise and fall of the Iberian cobras (Elapidae, Naja) in the context of their European and global fossil record","authors":"Andrea Villa, Ana B. Quadros, Massimo Delfino, Àngel H. Luján, Arnau Bolet, Isaac Casanovas‐Vilar, Josep M. Robles, David M. Alba","doi":"10.1002/spp2.1575","DOIUrl":"https://doi.org/10.1002/spp2.1575","url":null,"abstract":"Very few remains of elapid snakes are known from the Iberian Peninsula, but these include a probable endemic extinct species of cobra, <jats:italic>Naja iberica</jats:italic> from the Late Miocene. We here describe isolated cobra vertebrae from several Middle–Late Miocene localities in the Vallès‐Penedès Basin (Catalonia, Spain). All of these fossils are herein referred to an indeterminate species of the genus <jats:italic>Naja</jats:italic>. These remains are the first conclusive evidence that cobras were present in Iberia before the Messinian Salinity Crisis, and that they persisted there throughout the Miocene (and ultimately until the Pliocene). Recently, a phylogeny of extinct <jats:italic>Naja</jats:italic> based on cranial and vertebral morphology recognized <jats:italic>N</jats:italic>. <jats:italic>iberica</jats:italic> as a distinct lineage separate from the Central European one, represented mainly by <jats:italic>Naja romani</jats:italic>. However, due to taxonomic uncertainties, it is still unclear whether Iberian cobras were all part of a single lineage or whether several <jats:italic>Naja</jats:italic> lineages inhabited the Iberian Peninsula. They went extinct in Iberia before the end of the Pliocene. In the Vallès‐Penedès Basin, cobras were living in a mosaic environment, surviving through different phases characterized by different environmental features.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141769678","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}

{"title":"The postcranial anatomy and osteohistology of Terrestrisuchus gracilis (Archosauria, Crocodylomorpha) from the Late Triassic of Wales","authors":"Stephan N. F. Spiekman, Richard J. Butler, Susannah C. R. Maidment","doi":"10.1002/spp2.1577","DOIUrl":"https://doi.org/10.1002/spp2.1577","url":null,"abstract":"The earliest crocodylomorphs, known as non‐crocodyliform crocodylomorphs, first appeared during the Late Triassic. In contrast to extant crocodylians, which are all semi‐aquatic, early crocodylomorphs represent terrestrial taxa with a fully erect posture and in most cases a small body size. Their gracile skeletons suggest an active mode of life, possibly similar to contemporaneous, bipedal theropod dinosaurs. Despite this remarkable body plan, the postcranial morphology of early crocodylomorphs has rarely been documented in detail, restricting our ability to infer aspects of their functional morphology and evolution. Here, we provide a detailed description of the postcranium of <jats:italic>Terrestrisuchus gracilis</jats:italic>, a small‐bodied crocodylomorph from the Late Triassic of Pant‐y‐Ffynnon Quarry (southern Wales, UK), including a description of long bone tissues based on histological thin sections. Almost all elements of the postcranial skeleton have been preserved. The skeleton of <jats:italic>Terrestrisuchus gracilis</jats:italic> is highly gracile, even for a non‐crocodyliform crocodylomorph. Osteological correlates of the appendicular skeleton suggest that <jats:italic>Terrestrisuchus gracilis</jats:italic> had a digitigrade, quadrupedal posture. A quantitative analysis of limb robustness corroborates that <jats:italic>Terrestrisuchus gracilis</jats:italic> was a quadruped. Histological analysis suggests that all sampled specimens were skeletally immature and had fast growth at the time of death, as indicated by the lack of an external fundamental system and the predominance of fibrolamellar bone. The bone tissue is similar to that recently described for <jats:italic>Saltoposuchus connectens</jats:italic> and certain non‐crocodylomorph pseudosuchians, but differs from <jats:italic>Hesperosuchus agilis</jats:italic> and crocodyliforms, in which parallel‐fibred bone is more prevalent.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141769677","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}

{"title":"New aquatic insects from the Miocene of Australia with notes on the ecology and ontogeny of a new species of Chaoborus (Diptera, Chaoboridae)","authors":"Viktor Baranov, Michael Frese, Robert Beattie, Tara Djokic, Matthew R. McCurry","doi":"10.1002/spp2.1580","DOIUrl":"https://doi.org/10.1002/spp2.1580","url":null,"abstract":"We describe a diverse aquatic insect assemblage from McGraths Flat, a Miocene Lagerstätte in central New South Wales, Australia that includes representatives of Sialidae, Limoniidae, Chironomidae and Chaoboridae. The aquatic insect fossils from this deposit consist predominantly of larvae. These include a new species of phantom midge (<jats:italic>Chaoborus</jats:italic>, Chaoboridae), three morphotypes of non‐biting midges (Chironomidae), one morphotype of cranefly (Limoniidae) and one morphotype of alderfly (Sialidae). The large number of fossil specimens enabled us to study the ontogeny of the new midge species. We discerned growth rates in fossil larvae, using morphometry of all four instars of <jats:italic>Chaoborus</jats:italic>. The simultaneous presence of taxa associated with still water and taxa associated with flowing water supports the hypothesis that McGraths Flat was deposited in an isolated water body (oxbow lake/billabong) with influence from a river during high water events.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141769679","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}

{"title":"On the origin of the Oriental plane tree (Platanus orientalis L.)","authors":"Danae Danika, Benjamin Adroit, Dimitrios Velitzelos, Thomas Denk","doi":"10.1002/spp2.1576","DOIUrl":"https://doi.org/10.1002/spp2.1576","url":null,"abstract":"Oriental plane tree (<jats:italic>Platanus orientalis</jats:italic>) is native to the East Mediterranean region and sister to three western North American species, together forming the Pacific North American–European (PNA‐E) clade. Its sister clade, comprising several eastern North American–Mexican species, has been termed the Atlantic North American (ANA) clade. The origins of <jats:italic>P. orientalis</jats:italic> and the western North American–western Eurasian disjunction in the PNA‐E clade are poorly understood, with the North Atlantic and Bering land bridges being possible corridors for trans‐continental migration. Molecular phylogenetic studies suggested ancient hybridization between the ANA and PNA‐E clades prior to differentiation of modern species' lineages. We traced ANA‐ and PNA‐E‐specific leaf traits in the fossil record to locate areas of possible ancient hybridization. Leaf traits characteristic of the PNA‐E clade occurred in western North America (late Eocene of Montana, Early Miocene of Alaska) prior to appearing in the European fossil record. Fossil‐species with mixed PNA‐E–ANA leaf traits occurred in the Oligocene of Central Asia and Eocene and Miocene of western North America. In contrast, eastern North America and the Atlantic region hosted fossil‐species with leaf traits characteristic of modern ANA clade members. We propose that precursors of <jats:italic>Platanus orientalis</jats:italic> migrated to Europe via Beringia and through Central Asia. Initially, these Eurasian ancestors possessed ancestral PNA‐E clade leaf morphologies, which were gradually replaced by <jats:italic>P. orientalis</jats:italic>‐specific traits. Treated as a single fossil‐species, we document the evolution of <jats:italic>P. academiae</jats:italic> from predominately three‐lobed leaves in Miocene strata to narrowly five‐lobed leaves resembling modern <jats:italic>P. orientalis</jats:italic> in younger deposits of Greece.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141614023","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}

{"title":"Phylogenetic patterns in fossil and living billfishes (Istiophoriformes, Istiophoridae): evidence from the Central Mediterranean","authors":"Carlos De Gracia, Eduardo Villalobos‐Segura, Gustavo A. Ballen, Giorgio Carnevale, Jürgen Kriwet","doi":"10.1002/spp2.1559","DOIUrl":"https://doi.org/10.1002/spp2.1559","url":null,"abstract":"Study of the relationships of fossil and living billfishes is crucial for understanding the ecological drivers that control their biodiversity through time and how distributional patterns of extant populations may be affected by current abiotic events. Here we describe six istiophorid species that lived sympatrically in the central Mediterranean Sea during the Late Miocene, based on fossil istiophorids from Italy. Of these, †<jats:italic>Pizzikoskerma salentina</jats:italic>, †<jats:italic>Sicophasma macrocanalata</jats:italic>, †<jats:italic>Makaira adensa</jats:italic> and †<jats:italic>Makaira cyclovata</jats:italic> are new, while †<jats:italic>M. belgica</jats:italic> and †<jats:italic>M.</jats:italic> cf. <jats:italic>colonense</jats:italic> were described previously. The taxon <jats:italic>Istiophorus</jats:italic> is reported here for the first time in the Tortonian based on an unidentified species. We reconstructed the evolutionary direction of morphological traits by including the earliest known billfish, †<jats:italic>Hemmingwaya sarissa</jats:italic>, in our phylogenetic analysis as outgroup. A bill with circular cross‐section, 12 caudal vertebrae, a slim body and elongated first dorsal fin are shown to be plesiomorphic traits, while 13 caudal vertebrae, fusiform body, a shorter and pointed first dorsal fin, lateral process and quadrangular spines on the vertebral centra are traits associated with larger body sizes. The <jats:italic>Makaira</jats:italic> species described here have trabecular bone in the premaxilla forming the rostrum, an unusual pattern interpreted as an adaptation to reduce weight while simultaneously increasing body size. The fossil billfish assemblage suggests sea‐surface temperatures between 23°C and 24°C, much warmer than the modern central portion of the Mediterranean. The exquisite preservation of one specimen shows a trophic interaction between marlins and barracudas, the first direct evidence of predator–prey relationships in fossil istiophorids.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575382","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}

{"title":"Phylogenetic relationships of Malarossia Berezovsky (Eocene, Ukraine) and trends in the size evolution of the carditids (Bivalvia, Carditidae)","authors":"Damián E. Pérez, Anatoly A. Berezovsky","doi":"10.1002/spp2.1578","DOIUrl":"https://doi.org/10.1002/spp2.1578","url":null,"abstract":"Phylogenetic studies of fossil bivalves are crucial for understanding evolution in both extinct and extant species, and the family Carditidae has received limited research attention in this regard. The endemic genus <jats:italic>Malarossia</jats:italic> comes from the Eocene deposits of Ukraine and the diversity of carditids during this time have been broadly described from North America and Western Europe, although little is known beyond these regions. The aim of this study is to explore the phylogenetic position of the genus <jats:italic>Malarossia</jats:italic> and discuss trends in shell size among carditids. To accomplish this, a phylogenetic analysis was conducted using 51 species and 153 morphological characters. Our findings indicate that <jats:italic>Malarossia</jats:italic> represents an early diverging genus within the subfamily Scalaricarditinae, supported by morphological characters related to development and number of radial ribs, placement of pallial line, and umbones, among others. A wide range in shell size can be seen among carditids, with average values ranging from 3 to 100 mm. Notably, the larger sizes were predominantly observed during the Paleocene–Eocene, in the Venericorini. The Miodomeridinae and Scalaricarditinae had the smallest shell sizes, spanning from the Eocene to the present. Paedomorphic heterochronic processes are suggested for the origin of the small size observed in the Scalaricarditinae subfamily.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502936","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}

{"title":"Maiaspora: the hallmark of gleichenioid ferns (Gleicheniales) from the early Carboniferous","authors":"Dmitriy A. Mamontov, Duncan McLean, Olga A. Gavrilova","doi":"10.1002/spp2.1561","DOIUrl":"https://doi.org/10.1002/spp2.1561","url":null,"abstract":"The Palaeozoic origin of gleichenioid ferns (Gleicheniales) has aroused curiosity for almost a century. The oldest definite sign of this ancient clade is the spore wall ultrastructure of <jats:italic>Radiitheca dobranyana</jats:italic> from the Moscovian of central Europe. However, familial assignment of this fern fossil is uncertain. A comparison of its <jats:italic>in situ</jats:italic> spores with those of the dispersed genus <jats:italic>Maiaspora</jats:italic>, from the Visean, suggests that they may represent the same group of leptosporangiates. Although these spores have a common metareticuloid sculpture, the ultra‐thin structure of the dispersed counterparts remained unknown. Study of the ultrastructure of <jats:italic>Maiaspora concava</jats:italic> and <jats:italic>M. panopta</jats:italic> from central Russia and Northumberland (UK) using transmission electron microscopy shows that the wall of <jats:italic>Maiaspora</jats:italic> has a middle exospore layer composed of foliated lamellae. These spread from the base of the aperture slit to the subequatorial margins of kyrtome areas. The lamellae do not overlap the aperture slit and terminate at between two‐thirds and three‐quarters of the slit height. The miospores have a three‐layered exospore in the interradial areas, while non‐apertural parts of the exospore consist of two layers. Such an ultrastructure is shared by extant Gleicheniales and fossil <jats:italic>R. dobranyana</jats:italic>. The combined evidence from the morphology, ultrastructure and spatiotemporal distribution of <jats:italic>Maiaspora</jats:italic>, as well as radioisotope dating and additional plant macrofossils, suggests that the origin of the Gleicheniales stem was related to closure of the Rheic Ocean. Apparently, the first <jats:italic>Maiaspora</jats:italic>‐producing gleichenioids emerged as neoendemic terrestrial ferns on the peri‐Gondwanan volcanic arcs.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502935","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}

{"title":"Benthic pterobranchs from the Cambrian (Drumian) Marjum Konservat‐Lagerstätte of Utah","authors":"Rudy Lerosey‐Aubril, Jörg Maletz, Robert Coleman, Lucas Del Mouro, Robert R. Gaines, Jacob Skabelund, Javier Ortega‐Hernández","doi":"10.1002/spp2.1555","DOIUrl":"https://doi.org/10.1002/spp2.1555","url":null,"abstract":"Pterobranchs are rare in Cambrian strata of North America despite discoveries of more than 30 exceptionally preserved fossil biotas. Miaolingian pterobranchs from this continent typically form low‐diversity and low‐abundance assemblages. Here we describe an abundant pterobranch material from the Drumian Marjum Formation recently collected at the Gray Marjum Quarry in the House Range of Utah, USA. The faunule is composed of two new species: <jats:italic>Sphenoecium marjumensis</jats:italic>, an encrusting representative forming compact bushy colonies of more than 80 tubes with poorly developed rhizomes, and <jats:italic>Tarnagraptus cupidus</jats:italic>, an erect growing taxon characterized by intertwining stems and a monopodial colonial growth. Known in extant rhabdopleurids, this mode of colonial growth had hitherto never been observed in fossil pterobranchs. Its documentation in a <jats:italic>c</jats:italic>. 500‐myr‐old taxon attests to its deep origin in the evolutionary history of the group. Although the new species almost exclusively occur in the Marjum strata, this pterobranch faunule is broadly similar to those recovered from other Miaolingian Burgess Shale‐type deposits of North America in terms of genus‐level composition, species richness, and ecological structure. This may indicate that pterobranchs were poorly diverse components of animal communities at that time, or that they mostly thrived in more proximal shelf environments where conditions conducive to their preservation rarely developed. The common co‐occurrence of taxa with fundamentally different ecomorphotypes in the Miaolingian Series of North America strongly suggests an earlier phase of morphological diversification of benthic pterobranchs during the early Cambrian, which remains insufficiently documented by fossils.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140932937","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}

{"title":"The early Cambrian Bushizheia yangi and head segmentation in upper stem‐group euarthropods","authors":"Robert J. O'Flynn, Mark Williams, Mengxiao Yu, Jin Guo, Denis Audo, Michel Schmidt, Huijuan Mai, Yu Liu, Gregory D. Edgecombe","doi":"10.1002/spp2.1556","DOIUrl":"https://doi.org/10.1002/spp2.1556","url":null,"abstract":"<jats:italic>Bushizheia yangi</jats:italic> O'Flynn &amp; Liu, a euarthropod from the lower Cambrian (Series 2, Stage 3) Chengjiang Konservat‐Lagerstätte, possesses both raptorial frontal appendages sharing traits with stem‐group euarthropods, and deuteropodan characters shared by all extant euarthropods (e.g. dorsal arthrodization and arthropodization of all limbs). Microtomography of new specimens of <jats:italic>B</jats:italic>. <jats:italic>yangi</jats:italic> shows previously unknown details of head morphology: a six‐segmented head composed of an ocular segment that carries diminutive paired stalked eyes, a post‐ocular segment with deutocerebral frontal appendages, and four subsequent cephalic segments each bearing a pair of appendages. The phylogenetic position of <jats:italic>B</jats:italic>. <jats:italic>yangi</jats:italic> in the euarthropod stem‐group adds support to a six‐segmented head being an ancestral state for Deuteropoda. This study also reports the first occurrence of possible eggs closely associated with <jats:italic>B</jats:italic>. <jats:italic>yangi</jats:italic>. The homology of raptorial frontal appendages between lower stem‐group euarthropod radiodonts and deuteropods (i.e. upper stem and crown‐group euarthropods) is strengthened by similarity and phylogenetic continuity between <jats:italic>B</jats:italic>. <jats:italic>yangi</jats:italic>, its likely sister taxon <jats:italic>Kiisortoqia soperi</jats:italic> Stein, from the Sirius Passet Konservat‐Lagerstätte, and other euarthropod taxa.","PeriodicalId":48705,"journal":{"name":"Papers in Palaeontology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140932935","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}