The Experts below are selected from a list of 957 Experts worldwide ranked by ideXlab platform
Frank Scholze - One of the best experts on this subject based on the ideXlab platform.
-
reinvestigation of Conchostracans crustacea branchiopoda from the permian triassic transition in southwest china
Palaeoworld, 2020Co-Authors: Joerg W. Schneider, Frank Scholze, Shu-zhong Shen, Malte Backer, Hai-bo Wei, Marcel Hübner, Ying-ying Cui, Zhuo FengAbstract:Abstract Sedimentary deposits of the Permian–Triassic transition are well-exposed in numerous outcrops of South China. Depending on the palaeogeographic positions of the sections, their lithofacies vary from fully marine, shallow marine, lagoonal, lacustrine, and fluvial to alluvial. In the present study, Conchostracans (Crustacea: Branchiopoda) were newly collected from the continental deposits of the Kayitou and Jialingjiang formations around the Kangdian Highland elevated by the Emeishan Basalt in the southern Sichuan, western Guizhou, and northeastern Yunnan provinces. The conchostracan fauna of the Kayitou Formation is composed of Pseudestheria chatangensis, Euestheria fuyuanensis, and Euestheria sp. aff. E. gutta. These species occur in varying lithofacies types of different sections. In particular, the late Permian Pseudestheria chatangensis occurs in grey siltstones interbedded with pebbly sandstones, which are interpreted as lacustrine deposits. Euestheria fuyuanensis and Euestheria sp. aff. E. gutta were obtained from yellowish to greenish–grey clay- and siltstones, interpreted as coastal plain deposits. In comparison to other regions, occurrences of Euestheria gutta are indicative of an early Induan to Olenekian (Early Triassic) age. The fossil record of Euestheria fuyuanensis is so far restricted to a few occurrences in the Kayitou Formation of Southwest China and, therefore, using this species for long-distance biostratigraphic correlation requires further investigation. The distribution of late Permian pseudestheriid and Early Triassic euestheriid species in the respective sections possibly depends on the local lithofacies and, therefore, a diachronous age of the Kayitou Formation within the study area can be assumed. Additionally, Magniestheria sp. aff. M. mangaliensis and Magniestheria sp. aff. M. subcircularis were recorded in the Jialingjiang Formation, which represents a lithostratigraphic unit considered as late Early Triassic (Olenekian). Further investigations of both taxonomy and the real stratigraphic ranges of the conchostracan species as well as cross-correlations with other age data are recommended, in order to better constrain the position of the Permian–Triassic boundary and the specific timing of the terrestrial end-Permian mass extinction in continental deposits of Southwest China.
-
Late Paleozoic–early Mesozoic continental biostratigraphy — Links to the Standard Global Chronostratigraphic Scale
Palaeoworld, 2020Co-Authors: Joerg W. Schneider, Spencer G. Lucas, Hendrik Klein, Frank Scholze, Sebastian Voigt, Lorenzo Marchetti, Stanislav Opluštil, Ralf Werneburg, V. K. Golubev, James E. BarrickAbstract:Abstract Nonmarine biostratigraphic/biochronologic schemes have been created for all or parts of the late Carboniferous–Middle Triassic using palynomorphs, megafossil plants, Conchostracans, blattoid insects, tetrapod footprints and tetrapod body fossils, and these provide varied temporal resolution. Cross correlation of the nonmarine biochronologies to the Standard Global Chronostratigraphic Scale has been achieved in some parts of the late Carboniferous–Middle Triassic in locations where nonmarine and marine strata are intercalated, the nonmarine strata produce biochronologically significant fossils and the marine strata yield fusulinids, conodonts and/or ammonoids. Other cross correlations have been aided by magnetostratigraphy, chemostratigraphy and a growing database of radioisotopic ages. A synthetic nonmarine biochronology for the late Carboniferous–Middle Triassic based on all available nonmarine index fossils, integrated with the Standard Global Chronostratigraphic Scale, is presented here. The focus is on the nonmarine biostratigraphy/biochronology of blattoid insects, Conchostracans, branchiosaurid amphibians, tetrapod footprints and tetrapod body fossils within the biochronological framework of land-vertebrate faunachrons. Correlation to the Standard Global Chronostratigraphic Scale presented here is divided into seven time intervals: Pennsylvanian, Carboniferous–Permian boundary, Cisuralian, Guadalupian, Lopingian, Permian–Triassic boundary and Early to Middle Triassic. The insects, Conchostracans and branchiosaurs provide robust nonmarine correlations in the Pennsylvanian–Cisuralian, and the footprints and tetrapod body fossils provide robust correlations of varied precision within the entire Pennsylvanian–Middle Triassic. Radioisotopic ages are currently the strongest basis for cross correlation of the nonmarine biostratigraphy/biochronology to the Standard Global Chronostratigraphic Scale, particularly for the Pennsylvanian–Cisuralian. Chemostratigraphy and magnetostratigraphy thus far provide only limited links of nomarine and marine chronologies. Improvements in the nonmarine-marine correlations of late Paleozoic–Triassic Pangea require better alpha taxonomy and stratigraphic precision for the nonmarine fossil record integrated with more reliable radioisotopic ages and more extensive chemostratigraphic and magnetostratigraphic datasets.
-
Reinvestigation of Conchostracans (Crustacea: Branchiopoda) from the Permian–Triassic transition in Southwest China
Palaeoworld, 2020Co-Authors: Frank Scholze, Shu-zhong Shen, Malte Backer, Hai-bo Wei, Marcel Hübner, Ying-ying Cui, Zhuo Feng, Joerg W. SchneiderAbstract:Abstract Sedimentary deposits of the Permian–Triassic transition are well-exposed in numerous outcrops of South China. Depending on the palaeogeographic positions of the sections, their lithofacies vary from fully marine, shallow marine, lagoonal, lacustrine, and fluvial to alluvial. In the present study, Conchostracans (Crustacea: Branchiopoda) were newly collected from the continental deposits of the Kayitou and Jialingjiang formations around the Kangdian Highland elevated by the Emeishan Basalt in the southern Sichuan, western Guizhou, and northeastern Yunnan provinces. The conchostracan fauna of the Kayitou Formation is composed of Pseudestheria chatangensis, Euestheria fuyuanensis, and Euestheria sp. aff. E. gutta. These species occur in varying lithofacies types of different sections. In particular, the late Permian Pseudestheria chatangensis occurs in grey siltstones interbedded with pebbly sandstones, which are interpreted as lacustrine deposits. Euestheria fuyuanensis and Euestheria sp. aff. E. gutta were obtained from yellowish to greenish–grey clay- and siltstones, interpreted as coastal plain deposits. In comparison to other regions, occurrences of Euestheria gutta are indicative of an early Induan to Olenekian (Early Triassic) age. The fossil record of Euestheria fuyuanensis is so far restricted to a few occurrences in the Kayitou Formation of Southwest China and, therefore, using this species for long-distance biostratigraphic correlation requires further investigation. The distribution of late Permian pseudestheriid and Early Triassic euestheriid species in the respective sections possibly depends on the local lithofacies and, therefore, a diachronous age of the Kayitou Formation within the study area can be assumed. Additionally, Magniestheria sp. aff. M. mangaliensis and Magniestheria sp. aff. M. subcircularis were recorded in the Jialingjiang Formation, which represents a lithostratigraphic unit considered as late Early Triassic (Olenekian). Further investigations of both taxonomy and the real stratigraphic ranges of the conchostracan species as well as cross-correlations with other age data are recommended, in order to better constrain the position of the Permian–Triassic boundary and the specific timing of the terrestrial end-Permian mass extinction in continental deposits of Southwest China.
-
Late Permian Conchostracans (Crustacea, Branchiopoda) from continental deposits in the Moscow Syneclise, Russia
Journal of Paleontology, 2018Co-Authors: Frank Scholze, Joerg W. Schneider, V. K. Golubev, Grzegorz Niedźwiedzki, A. G. SennikovAbstract:The Moscow Syneclise on the East European Platform is an important area for the study of the continental biota of late Permian to Early Triassic age in continuous sections. This study attempts a taxonomic description of the late Permian conchostracan fauna of this area. The rich, new material was collected, bed by bed, during geological and paleontological excavations of lacustrine and fluvial deposits of the Obnora Formation and Vokhma Formation of the late Permian Zhukovian Regional Stage near the towns of Vyazniki and Gorokhovets. The conchostracan fauna of the Zhukovian Regional Stage consists predominantly of Pseudestheria and less frequently of Palaeolimnadiopsis. In the earliest Triassic Vokhmian Regional Stage, a more diverse fauna including Euestheria, Magniestheria, Cornia, Palaeolimnadiopsis, and Rossolimnadiopsis was already recorded. The preliminary taxonomic determination of the pseudestheriids from the Zhukovian Regional Stage is intended to serve as a prerequisite for future studies of late Permian conchostracan biostratigraphy on the regional to interregional scale.
-
An enigmatic ‘conchostracan’ fauna in the eastern Dead Sea region of Jordan: First records of Rossolimnadiopsis Novozhilov from the Early Triassic Ma'in Formation
Palaeogeography Palaeoclimatology Palaeoecology, 2017Co-Authors: Frank Scholze, Joerg W. Schneider, Sebastian Voigt, V. K. Golubev, A. G. Sennikov, Abdalla Abu Hamad, Dieter UhlAbstract:Abstract The Late Permian–Early Triassic sedimentary succession in the eastern Dead Sea Region of Jordan was surveyed for Conchostracans (Crustacea: Branchiopoda). Whereas their occurrence in the Middle–Late Permian Umm Irna Formation could not be confirmed, the overlying Ma'in Formation contained a fauna comprising Rossolimnadiopsis Novozhilov and other, thus far, taxonomically undetermined Conchostracans. Here, a new species, Rossolimnadiopsis hanskerpi nov. sp., is described and figured. It shows a very distinctive concavely curved dorsal margin and an elevated, outwardly curved semi-circular flange. Rossolimnadiopsis hanskerpi nov. sp. occurs in dark gray, laminated, lacustrine, siltstones of the Ma'in Formation (Nimra Member), which is considered to be of Early Triassic age. Based on literature data, Rossolimnadiopsis was previously recorded only from two localities in the Moscow syncline in Central Russia. In addition to Jordan, the genus has been identified in India and possibly in Germany. All these occurrences seem to be restricted to a narrow stratigraphic interval ranging from the Late Permian to the Early Triassic.
Joerg W. Schneider - One of the best experts on this subject based on the ideXlab platform.
-
reinvestigation of Conchostracans crustacea branchiopoda from the permian triassic transition in southwest china
Palaeoworld, 2020Co-Authors: Joerg W. Schneider, Frank Scholze, Shu-zhong Shen, Malte Backer, Hai-bo Wei, Marcel Hübner, Ying-ying Cui, Zhuo FengAbstract:Abstract Sedimentary deposits of the Permian–Triassic transition are well-exposed in numerous outcrops of South China. Depending on the palaeogeographic positions of the sections, their lithofacies vary from fully marine, shallow marine, lagoonal, lacustrine, and fluvial to alluvial. In the present study, Conchostracans (Crustacea: Branchiopoda) were newly collected from the continental deposits of the Kayitou and Jialingjiang formations around the Kangdian Highland elevated by the Emeishan Basalt in the southern Sichuan, western Guizhou, and northeastern Yunnan provinces. The conchostracan fauna of the Kayitou Formation is composed of Pseudestheria chatangensis, Euestheria fuyuanensis, and Euestheria sp. aff. E. gutta. These species occur in varying lithofacies types of different sections. In particular, the late Permian Pseudestheria chatangensis occurs in grey siltstones interbedded with pebbly sandstones, which are interpreted as lacustrine deposits. Euestheria fuyuanensis and Euestheria sp. aff. E. gutta were obtained from yellowish to greenish–grey clay- and siltstones, interpreted as coastal plain deposits. In comparison to other regions, occurrences of Euestheria gutta are indicative of an early Induan to Olenekian (Early Triassic) age. The fossil record of Euestheria fuyuanensis is so far restricted to a few occurrences in the Kayitou Formation of Southwest China and, therefore, using this species for long-distance biostratigraphic correlation requires further investigation. The distribution of late Permian pseudestheriid and Early Triassic euestheriid species in the respective sections possibly depends on the local lithofacies and, therefore, a diachronous age of the Kayitou Formation within the study area can be assumed. Additionally, Magniestheria sp. aff. M. mangaliensis and Magniestheria sp. aff. M. subcircularis were recorded in the Jialingjiang Formation, which represents a lithostratigraphic unit considered as late Early Triassic (Olenekian). Further investigations of both taxonomy and the real stratigraphic ranges of the conchostracan species as well as cross-correlations with other age data are recommended, in order to better constrain the position of the Permian–Triassic boundary and the specific timing of the terrestrial end-Permian mass extinction in continental deposits of Southwest China.
-
Late Paleozoic–early Mesozoic continental biostratigraphy — Links to the Standard Global Chronostratigraphic Scale
Palaeoworld, 2020Co-Authors: Joerg W. Schneider, Spencer G. Lucas, Hendrik Klein, Frank Scholze, Sebastian Voigt, Lorenzo Marchetti, Stanislav Opluštil, Ralf Werneburg, V. K. Golubev, James E. BarrickAbstract:Abstract Nonmarine biostratigraphic/biochronologic schemes have been created for all or parts of the late Carboniferous–Middle Triassic using palynomorphs, megafossil plants, Conchostracans, blattoid insects, tetrapod footprints and tetrapod body fossils, and these provide varied temporal resolution. Cross correlation of the nonmarine biochronologies to the Standard Global Chronostratigraphic Scale has been achieved in some parts of the late Carboniferous–Middle Triassic in locations where nonmarine and marine strata are intercalated, the nonmarine strata produce biochronologically significant fossils and the marine strata yield fusulinids, conodonts and/or ammonoids. Other cross correlations have been aided by magnetostratigraphy, chemostratigraphy and a growing database of radioisotopic ages. A synthetic nonmarine biochronology for the late Carboniferous–Middle Triassic based on all available nonmarine index fossils, integrated with the Standard Global Chronostratigraphic Scale, is presented here. The focus is on the nonmarine biostratigraphy/biochronology of blattoid insects, Conchostracans, branchiosaurid amphibians, tetrapod footprints and tetrapod body fossils within the biochronological framework of land-vertebrate faunachrons. Correlation to the Standard Global Chronostratigraphic Scale presented here is divided into seven time intervals: Pennsylvanian, Carboniferous–Permian boundary, Cisuralian, Guadalupian, Lopingian, Permian–Triassic boundary and Early to Middle Triassic. The insects, Conchostracans and branchiosaurs provide robust nonmarine correlations in the Pennsylvanian–Cisuralian, and the footprints and tetrapod body fossils provide robust correlations of varied precision within the entire Pennsylvanian–Middle Triassic. Radioisotopic ages are currently the strongest basis for cross correlation of the nonmarine biostratigraphy/biochronology to the Standard Global Chronostratigraphic Scale, particularly for the Pennsylvanian–Cisuralian. Chemostratigraphy and magnetostratigraphy thus far provide only limited links of nomarine and marine chronologies. Improvements in the nonmarine-marine correlations of late Paleozoic–Triassic Pangea require better alpha taxonomy and stratigraphic precision for the nonmarine fossil record integrated with more reliable radioisotopic ages and more extensive chemostratigraphic and magnetostratigraphic datasets.
-
Reinvestigation of Conchostracans (Crustacea: Branchiopoda) from the Permian–Triassic transition in Southwest China
Palaeoworld, 2020Co-Authors: Frank Scholze, Shu-zhong Shen, Malte Backer, Hai-bo Wei, Marcel Hübner, Ying-ying Cui, Zhuo Feng, Joerg W. SchneiderAbstract:Abstract Sedimentary deposits of the Permian–Triassic transition are well-exposed in numerous outcrops of South China. Depending on the palaeogeographic positions of the sections, their lithofacies vary from fully marine, shallow marine, lagoonal, lacustrine, and fluvial to alluvial. In the present study, Conchostracans (Crustacea: Branchiopoda) were newly collected from the continental deposits of the Kayitou and Jialingjiang formations around the Kangdian Highland elevated by the Emeishan Basalt in the southern Sichuan, western Guizhou, and northeastern Yunnan provinces. The conchostracan fauna of the Kayitou Formation is composed of Pseudestheria chatangensis, Euestheria fuyuanensis, and Euestheria sp. aff. E. gutta. These species occur in varying lithofacies types of different sections. In particular, the late Permian Pseudestheria chatangensis occurs in grey siltstones interbedded with pebbly sandstones, which are interpreted as lacustrine deposits. Euestheria fuyuanensis and Euestheria sp. aff. E. gutta were obtained from yellowish to greenish–grey clay- and siltstones, interpreted as coastal plain deposits. In comparison to other regions, occurrences of Euestheria gutta are indicative of an early Induan to Olenekian (Early Triassic) age. The fossil record of Euestheria fuyuanensis is so far restricted to a few occurrences in the Kayitou Formation of Southwest China and, therefore, using this species for long-distance biostratigraphic correlation requires further investigation. The distribution of late Permian pseudestheriid and Early Triassic euestheriid species in the respective sections possibly depends on the local lithofacies and, therefore, a diachronous age of the Kayitou Formation within the study area can be assumed. Additionally, Magniestheria sp. aff. M. mangaliensis and Magniestheria sp. aff. M. subcircularis were recorded in the Jialingjiang Formation, which represents a lithostratigraphic unit considered as late Early Triassic (Olenekian). Further investigations of both taxonomy and the real stratigraphic ranges of the conchostracan species as well as cross-correlations with other age data are recommended, in order to better constrain the position of the Permian–Triassic boundary and the specific timing of the terrestrial end-Permian mass extinction in continental deposits of Southwest China.
-
Late Permian Conchostracans (Crustacea, Branchiopoda) from continental deposits in the Moscow Syneclise, Russia
Journal of Paleontology, 2018Co-Authors: Frank Scholze, Joerg W. Schneider, V. K. Golubev, Grzegorz Niedźwiedzki, A. G. SennikovAbstract:The Moscow Syneclise on the East European Platform is an important area for the study of the continental biota of late Permian to Early Triassic age in continuous sections. This study attempts a taxonomic description of the late Permian conchostracan fauna of this area. The rich, new material was collected, bed by bed, during geological and paleontological excavations of lacustrine and fluvial deposits of the Obnora Formation and Vokhma Formation of the late Permian Zhukovian Regional Stage near the towns of Vyazniki and Gorokhovets. The conchostracan fauna of the Zhukovian Regional Stage consists predominantly of Pseudestheria and less frequently of Palaeolimnadiopsis. In the earliest Triassic Vokhmian Regional Stage, a more diverse fauna including Euestheria, Magniestheria, Cornia, Palaeolimnadiopsis, and Rossolimnadiopsis was already recorded. The preliminary taxonomic determination of the pseudestheriids from the Zhukovian Regional Stage is intended to serve as a prerequisite for future studies of late Permian conchostracan biostratigraphy on the regional to interregional scale.
-
An enigmatic ‘conchostracan’ fauna in the eastern Dead Sea region of Jordan: First records of Rossolimnadiopsis Novozhilov from the Early Triassic Ma'in Formation
Palaeogeography Palaeoclimatology Palaeoecology, 2017Co-Authors: Frank Scholze, Joerg W. Schneider, Sebastian Voigt, V. K. Golubev, A. G. Sennikov, Abdalla Abu Hamad, Dieter UhlAbstract:Abstract The Late Permian–Early Triassic sedimentary succession in the eastern Dead Sea Region of Jordan was surveyed for Conchostracans (Crustacea: Branchiopoda). Whereas their occurrence in the Middle–Late Permian Umm Irna Formation could not be confirmed, the overlying Ma'in Formation contained a fauna comprising Rossolimnadiopsis Novozhilov and other, thus far, taxonomically undetermined Conchostracans. Here, a new species, Rossolimnadiopsis hanskerpi nov. sp., is described and figured. It shows a very distinctive concavely curved dorsal margin and an elevated, outwardly curved semi-circular flange. Rossolimnadiopsis hanskerpi nov. sp. occurs in dark gray, laminated, lacustrine, siltstones of the Ma'in Formation (Nimra Member), which is considered to be of Early Triassic age. Based on literature data, Rossolimnadiopsis was previously recorded only from two localities in the Moscow syncline in Central Russia. In addition to Jordan, the genus has been identified in India and possibly in Germany. All these occurrences seem to be restricted to a narrow stratigraphic interval ranging from the Late Permian to the Early Triassic.
Spencer G. Lucas - One of the best experts on this subject based on the ideXlab platform.
-
Late Paleozoic–early Mesozoic continental biostratigraphy — Links to the Standard Global Chronostratigraphic Scale
Palaeoworld, 2020Co-Authors: Joerg W. Schneider, Spencer G. Lucas, Hendrik Klein, Frank Scholze, Sebastian Voigt, Lorenzo Marchetti, Stanislav Opluštil, Ralf Werneburg, V. K. Golubev, James E. BarrickAbstract:Abstract Nonmarine biostratigraphic/biochronologic schemes have been created for all or parts of the late Carboniferous–Middle Triassic using palynomorphs, megafossil plants, Conchostracans, blattoid insects, tetrapod footprints and tetrapod body fossils, and these provide varied temporal resolution. Cross correlation of the nonmarine biochronologies to the Standard Global Chronostratigraphic Scale has been achieved in some parts of the late Carboniferous–Middle Triassic in locations where nonmarine and marine strata are intercalated, the nonmarine strata produce biochronologically significant fossils and the marine strata yield fusulinids, conodonts and/or ammonoids. Other cross correlations have been aided by magnetostratigraphy, chemostratigraphy and a growing database of radioisotopic ages. A synthetic nonmarine biochronology for the late Carboniferous–Middle Triassic based on all available nonmarine index fossils, integrated with the Standard Global Chronostratigraphic Scale, is presented here. The focus is on the nonmarine biostratigraphy/biochronology of blattoid insects, Conchostracans, branchiosaurid amphibians, tetrapod footprints and tetrapod body fossils within the biochronological framework of land-vertebrate faunachrons. Correlation to the Standard Global Chronostratigraphic Scale presented here is divided into seven time intervals: Pennsylvanian, Carboniferous–Permian boundary, Cisuralian, Guadalupian, Lopingian, Permian–Triassic boundary and Early to Middle Triassic. The insects, Conchostracans and branchiosaurs provide robust nonmarine correlations in the Pennsylvanian–Cisuralian, and the footprints and tetrapod body fossils provide robust correlations of varied precision within the entire Pennsylvanian–Middle Triassic. Radioisotopic ages are currently the strongest basis for cross correlation of the nonmarine biostratigraphy/biochronology to the Standard Global Chronostratigraphic Scale, particularly for the Pennsylvanian–Cisuralian. Chemostratigraphy and magnetostratigraphy thus far provide only limited links of nomarine and marine chronologies. Improvements in the nonmarine-marine correlations of late Paleozoic–Triassic Pangea require better alpha taxonomy and stratigraphic precision for the nonmarine fossil record integrated with more reliable radioisotopic ages and more extensive chemostratigraphic and magnetostratigraphic datasets.
-
Abstract—Conchostracans from the Lower Jurassic Whitmore Point Member of the Moenave Formation at
2015Co-Authors: Spencer G. Lucas, Andrew R. C. MilnerAbstract:Johnson Farm, southwestern Utah, are preserved as three-dimensional, carbonate-replaced shells. The presence of numerous, closely-spaced growth lines that extend onto the umbo, no evident sculpture, and the absence of nodes, spines or a recurved posterior margin, support assignment of the Johnson Farm Conchostracans to Euestheria. However, given the chaotic state of conchostracan taxonomy, no species-level assignment is attempted. Euestheria has a temporal range of Devonian-Cretaceous, so its occurrence at Johnson Farm is of no biostratigraphic signifi-cance. However, the presence of Conchostracans in the Whitmore Point Member is further evidence that the paleo-lake in which it was deposited was a shallow and ephemeral body of water
-
Position of the Triassic–Jurassic boundary and timing of the end-Triassic extinctions on land: Data from the Moenave Formation on the southern Colorado Plateau, USA
Palaeogeography Palaeoclimatology Palaeoecology, 2011Co-Authors: Spencer G. Lucas, Lawrence H. Tanner, Linda Donohoo-hurley, John W. Geissman, H. W. Kozur, Andrew B. Heckert, Robert E. WeemsAbstract:Strata of the Moenave Formation on and adjacent to the southern Colorado Plateau in Utah–Arizona, U.S.A., represent one of the best known and most stratigraphically continuous, complete and fossiliferous terrestrial sections across the Triassic–Jurassic boundary. We present a synthesis of new biostratigraphic and magnetostratigraphic data collected from across the Moenave Formation outcrop belt, which extends from the St. George area in southwestern Utah to the Tuba City area in northern Arizona. These data include palynomorphs, Conchostracans and vertebrate fossils (including footprints) and a composite polarity record based on four overlapping magnetostratigraphic sections. Placement of the Triassic–Jurassic boundary in strata of the Moenave Formation has long been imprecise and debatable, but these new data (especially the Conchostracans) allow us to place the Triassic–Jurassic boundary relatively precisely in the middle part of the Whitmore Point Member of the Moenave Formation, stratigraphically well above the highest occurrence of crurotarsan body fossils or footprints. Correlation to marine sections based on this placement indicates that major terrestrial vertebrate extinctions preceded marine extinctions across the Triassic–Jurassic boundary and therefore were likely unrelated to the Central Atlantic Magmatic Province (CAMP) volcanism.
-
CONCHOSTRACA FROM THE LOWER JURASSIC WHITMORE POINT MEMBER OF THE MOENAVE FORMATION, JOHNSON FARM, SOUTHWESTERN UTAH
2006Co-Authors: Spencer G. Lucas, Andrew R. C. MilnerAbstract:Conchostracans from the Lower Jurassic Whitmore Point Member of the Moenave Formation at Johnson Farm, southwestern Utah, are preserved as three-dimensional, carbonate-replaced shells. The presence of numerous, closely-spaced growth lines that extend onto the umbo, no evident sculpture, and the absence of nodes, spines or a recurved posterior margin, support assignment of the Johnson Farm Conchostracans to Euestheria. However, given the chaotic state of conchostracan taxonomy, no species-level assignment is attempted. Euestheria has a temporal range of Devonian-Cretaceous, so its occurrence at Johnson Farm is of no biostratigraphic signifi- cance. However, the presence of Conchostracans in the Whitmore Point Member is further evidence that the paleo- lake in which it was deposited was a shallow and ephemeral body of water.
Ralf Werneburg - One of the best experts on this subject based on the ideXlab platform.
-
Late Paleozoic–early Mesozoic continental biostratigraphy — Links to the Standard Global Chronostratigraphic Scale
Palaeoworld, 2020Co-Authors: Joerg W. Schneider, Spencer G. Lucas, Hendrik Klein, Frank Scholze, Sebastian Voigt, Lorenzo Marchetti, Stanislav Opluštil, Ralf Werneburg, V. K. Golubev, James E. BarrickAbstract:Abstract Nonmarine biostratigraphic/biochronologic schemes have been created for all or parts of the late Carboniferous–Middle Triassic using palynomorphs, megafossil plants, Conchostracans, blattoid insects, tetrapod footprints and tetrapod body fossils, and these provide varied temporal resolution. Cross correlation of the nonmarine biochronologies to the Standard Global Chronostratigraphic Scale has been achieved in some parts of the late Carboniferous–Middle Triassic in locations where nonmarine and marine strata are intercalated, the nonmarine strata produce biochronologically significant fossils and the marine strata yield fusulinids, conodonts and/or ammonoids. Other cross correlations have been aided by magnetostratigraphy, chemostratigraphy and a growing database of radioisotopic ages. A synthetic nonmarine biochronology for the late Carboniferous–Middle Triassic based on all available nonmarine index fossils, integrated with the Standard Global Chronostratigraphic Scale, is presented here. The focus is on the nonmarine biostratigraphy/biochronology of blattoid insects, Conchostracans, branchiosaurid amphibians, tetrapod footprints and tetrapod body fossils within the biochronological framework of land-vertebrate faunachrons. Correlation to the Standard Global Chronostratigraphic Scale presented here is divided into seven time intervals: Pennsylvanian, Carboniferous–Permian boundary, Cisuralian, Guadalupian, Lopingian, Permian–Triassic boundary and Early to Middle Triassic. The insects, Conchostracans and branchiosaurs provide robust nonmarine correlations in the Pennsylvanian–Cisuralian, and the footprints and tetrapod body fossils provide robust correlations of varied precision within the entire Pennsylvanian–Middle Triassic. Radioisotopic ages are currently the strongest basis for cross correlation of the nonmarine biostratigraphy/biochronology to the Standard Global Chronostratigraphic Scale, particularly for the Pennsylvanian–Cisuralian. Chemostratigraphy and magnetostratigraphy thus far provide only limited links of nomarine and marine chronologies. Improvements in the nonmarine-marine correlations of late Paleozoic–Triassic Pangea require better alpha taxonomy and stratigraphic precision for the nonmarine fossil record integrated with more reliable radioisotopic ages and more extensive chemostratigraphic and magnetostratigraphic datasets.
-
Conchostracans in continental deposits of the zechstein buntsandstein transition in central germany taxonomy and biostratigraphic implications for the position of the permian triassic boundary within the zechstein group
Palaeogeography Palaeoclimatology Palaeoecology, 2016Co-Authors: Frank Scholze, Jörg W. Schneider, Ralf WerneburgAbstract:Abstract The end-Permian mass extinction marks the largest biotic crisis in the geologic record. The stratigraphic position of this boundary in continental deposits is still under discussion. In the present study, Conchostracans from the Zechstein–Buntsandstein (Late Permian to Early Triassic) transition in central Germany have been taxonomically reinvestigated in order to better understand their utility for fine-scale biostratigraphy in continental Permian–Triassic boundary sections. The studied material was obtained from both collections and recent sampling activities in classical key sections and new outcrops of the Zechstein and Buntsandstein Groups. The sedimentary environments of the conchostracan occurrences are interpreted as lacustrine to fluvial facies depending on the paleogeographic position within the basin of the respective sections. The conchostracan fauna in the Zechstein–Buntsandstein transition consists of Euestheria gutta, Palaeolimnadiopsis vilujensis, Cornia germari, Estheriella marginostriata, Estheriella costata, Estheriella nodosocostata, Magniestheria mangaliensis, and Euestheria nordvikensis. Based on comparison with the Early Triassic conchostracan record in the Moscow syncline, the Palaeolimnadiopsis vilujensis–Euestheria gutta association in the upper part of the Fulda Formation indicates both its Early Triassic age and a position of the continental Permian–Triassic boundary within the Zechstein Group.
-
Conchostracans in continental deposits of the Zechstein–Buntsandstein transition in central Germany: Taxonomy and biostratigraphic implications for the position of the Permian–Triassic boundary within the Zechstein Group
Palaeogeography Palaeoclimatology Palaeoecology, 2016Co-Authors: Frank Scholze, Jörg W. Schneider, Ralf WerneburgAbstract:Abstract The end-Permian mass extinction marks the largest biotic crisis in the geologic record. The stratigraphic position of this boundary in continental deposits is still under discussion. In the present study, Conchostracans from the Zechstein–Buntsandstein (Late Permian to Early Triassic) transition in central Germany have been taxonomically reinvestigated in order to better understand their utility for fine-scale biostratigraphy in continental Permian–Triassic boundary sections. The studied material was obtained from both collections and recent sampling activities in classical key sections and new outcrops of the Zechstein and Buntsandstein Groups. The sedimentary environments of the conchostracan occurrences are interpreted as lacustrine to fluvial facies depending on the paleogeographic position within the basin of the respective sections. The conchostracan fauna in the Zechstein–Buntsandstein transition consists of Euestheria gutta, Palaeolimnadiopsis vilujensis, Cornia germari, Estheriella marginostriata, Estheriella costata, Estheriella nodosocostata, Magniestheria mangaliensis, and Euestheria nordvikensis. Based on comparison with the Early Triassic conchostracan record in the Moscow syncline, the Palaeolimnadiopsis vilujensis–Euestheria gutta association in the upper part of the Fulda Formation indicates both its Early Triassic age and a position of the continental Permian–Triassic boundary within the Zechstein Group.
Diying Huang - One of the best experts on this subject based on the ideXlab platform.
-
Pemphilimnadiopsis cheni sp. nov. (Branchiopoda: Diplostraca: Spinicaudata) from the Upper Carboniferous of East Hebei, China and its biostratigraphic significance
Palaeoentomology, 2019Co-Authors: Huanyu Liao, Yanbin Shen, Jian Gao, Diying HuangAbstract:A new conchostracan species Pemphilimnadiopsis cheni sp. nov. is found in the upper section of the Pennsylvanian Benxi Formation in Kaiping, Tangshan City, Hebei Province, China and is closely related to the type species of the genus, P. ortoni. This finding is the fifth record of the Carboniferous Conchostracans in China. Its finding gives evidence that the Benxi Formation in Kaiping, Tangshan City can be restricted into middle-late Moscovian to early Kasimovian and the present conchostracan layers more likely correspond to the early Kasimovian. Moreover, the first described Palaeozoic insects come from the same layers in the Kaiping Basin. This study indicates the age of these fossil insects would be close to the boundary of Moscovian and Kasimovian and more likely the early Kasimovian.
-
Serrated microstructures on carapaces of Eosestheria (Branchiopoda: Diplostraca) in the Early Cretaceous Jehol Biota and discussion on the taxonomic value of these structures
Cretaceous Research, 2019Co-Authors: Huanyu Liao, Yanbin Shen, Diying HuangAbstract:Abstract Serrated microstructures on the growth lines of some fossil Conchostracans have been previously regarded as a key characteristic for judging the family Afrograptidae. Consequently, more than 20 relatively diverse genera were assigned into Afrograptidae based on the presence of serrated structures. This has created a series of taxonomic disputes in regard to fossil Conchostracans. In this study, serrated microstructures on the growth lines of two species, namely, Eosestheria ovata and E. middendorfii, in the Early Cretaceous Jehol Biota are reported and described in detail. Our microstructural study shows that these structures are pit-shaped and are actually insertion remains of setae. Such microstructures commonly exist on the growth lines of some extant spinicaudatans. The setae probably served a sensory function. The presence or absence of these setae in extant species of the same genus can be variable and size of the setae of the same species can also be variable. Thus they are not appropriate to be considered as possessing important taxonomic value. Based on this conclusion, the species of the family Afrograptidae are listed in conjunction with the results of our previous study.
-
Discussions on the age of Daohugou fauna—evidence from invertebrates
'Elsevier BV', 2018Co-Authors: Diying Huang, Yanbin Shen, Nel André, Selden, Paul A., Qibin LinAbstract:Volcanic tuff deposits near Daohugou village, Ningcheng County of Inner Monogolia have yielded many well-preserved fossils. Here we briefly introduce our recent findings of invertebrates from the Daohugou fauna: Mainly insects, Conchostracans, anostra-cans, and spiders. The age of the Daohugou fauna is considered to be Middle Jurassic on the basis of an analysis of various invertebrates especially insects and Conchostracans, showing strong similarities to the Yanliao fauna of north China and the Karatau fauna of Kazakhstan
-
Conchostracans of the middle late jurassic daohugou and linglongta beds in ne china
Palaeoworld, 2017Co-Authors: Huanyu Liao, Yanbin Shen, Diying HuangAbstract:Abstract The Yanliao biota is widely distributed in western Liaoning, northern Hebei, and the areas adjacent to eastern Inner Mongolia. The biota is excavated from two typical fossil-bearing beds: the Daohugou fossil-bearing beds in Daohugou, Jiangzhangzi, and Chentaizi, Wuhua Town, Ningcheng County, Inner Mongolia; and the Linglongta fossil-bearing beds in Daxishan, Linglongta Town, Jianchang County, Liaoning Province and Bawanggou, Mutoudeng Town, Qinglong County, Hebei Province. Previously, it was thought that the Daohugou and Linglongta beds are correlatable in age and fossil content and that the Conchostracans from both the Daohugou and Linglongta beds could all be attributed to the genus Euestheria. However, clear punctae but no reticulations are observed on all Conchostracans collected from the Daohugou beds, which excludes them from Euestheria. In this study, only one species, Triglypta haifanggouensis n. comb., is recognized based on detailed investigations of the ornamentations of hundreds of specimens from the Daohugou beds. In addition to the recently reported Tianzhuestheria jianchangensis, another species, Liaoxiestheria linglongtaensis n. gen. n. sp., is identified in this study based on a large number of specimens from the Linglongta beds in Daxishan. Isotope analysis has shown that the Daohugou and Linglongta beds are approximately 165 Ma and 160 Ma old, respectively. Therefore, the fossils from the Daohugou beds represent an early assemblage and the fossils from the Linglongta beds represent a late assemblage of the Yanliao biota. This study indicates that the conchostracan assemblage of the Daohugou beds is a typical Triglypta–Qaidamestheria assemblage, which is widely distributed in the Middle Jurassic of North China, and the conchostracan assemblage of the Linglongta beds represents the late, succeeding Triglypta–Qaidamestheria assemblage.
-
Conchostracans of the Middle–Late Jurassic Daohugou and Linglongta beds in NE China
Palaeoworld, 2017Co-Authors: Huanyu Liao, Yanbin Shen, Diying HuangAbstract:Abstract The Yanliao biota is widely distributed in western Liaoning, northern Hebei, and the areas adjacent to eastern Inner Mongolia. The biota is excavated from two typical fossil-bearing beds: the Daohugou fossil-bearing beds in Daohugou, Jiangzhangzi, and Chentaizi, Wuhua Town, Ningcheng County, Inner Mongolia; and the Linglongta fossil-bearing beds in Daxishan, Linglongta Town, Jianchang County, Liaoning Province and Bawanggou, Mutoudeng Town, Qinglong County, Hebei Province. Previously, it was thought that the Daohugou and Linglongta beds are correlatable in age and fossil content and that the Conchostracans from both the Daohugou and Linglongta beds could all be attributed to the genus Euestheria. However, clear punctae but no reticulations are observed on all Conchostracans collected from the Daohugou beds, which excludes them from Euestheria. In this study, only one species, Triglypta haifanggouensis n. comb., is recognized based on detailed investigations of the ornamentations of hundreds of specimens from the Daohugou beds. In addition to the recently reported Tianzhuestheria jianchangensis, another species, Liaoxiestheria linglongtaensis n. gen. n. sp., is identified in this study based on a large number of specimens from the Linglongta beds in Daxishan. Isotope analysis has shown that the Daohugou and Linglongta beds are approximately 165 Ma and 160 Ma old, respectively. Therefore, the fossils from the Daohugou beds represent an early assemblage and the fossils from the Linglongta beds represent a late assemblage of the Yanliao biota. This study indicates that the conchostracan assemblage of the Daohugou beds is a typical Triglypta–Qaidamestheria assemblage, which is widely distributed in the Middle Jurassic of North China, and the conchostracan assemblage of the Linglongta beds represents the late, succeeding Triglypta–Qaidamestheria assemblage.