Bettina Reichenbacher - Academia.edu (original) (raw)
Papers by Bettina Reichenbacher
Molecular Phylogenetics and Evolution
Here we explain why the species name Aphaniops hormuzensis (Teimori, Esmaeili, Hamidan, Reichenba... more Here we explain why the species name Aphaniops hormuzensis (Teimori, Esmaeili, Hamidan, Reichenbacher, 2018) should be considered as valid. As a consequence, the species name Aphaniops teimorii Freyhof and Yogurtcuoglu, 2020 should be treated as a junior synonym of A. hormuzensis .
Palaeogeography, Palaeoclimatology, Palaeoecology, 2021
Abstract The North Alpine Foreland Basin (NAFB) comprises one of the most complete sedimentary re... more Abstract The North Alpine Foreland Basin (NAFB) comprises one of the most complete sedimentary records of the Oligocene and Miocene. Driven by global sea-level fluctuations, vast sedimentary influx and tectonic movement. The locality of Unterrudling near Eferding (Upper Austria) exposes the largest succession of sedimentary deposits from the late Oligocene in the eastern NAFB. Additionally, this section shows the facies transition from the shallow-water Linz-Melk Formation to the deep-water Eferding Formation. In this work, the fossil fauna and flora of the Eferding Formation as well as its lithology are re-evaluated using a multidisciplinary approach to gain new insights into the palaeoenvironment, palaeoclimate, and palaeoecology. A transgressive sequence is documented using sedimentological and ichnological data. Furthermore, a correlation to the late Chattian transgressive Ch-3 sequence is suggested. The impact of rising sea level on marine biota is shown in detail by analysing various groups (Bivalvia, Echinodermata, Anthozoa, Foraminifera, Chondrichthyes, Osteichthyes), with several newly reported species from the Eferding Formation. Moreover, washed in plant material was analysed for the interpretation of the terrestrial climate indicating mainly humid subtropical conditions. Finally, the presence of phosphatic nodules indicates eutrophication on the shelf environment and the possibility of upwelling currents.
Journal of Vertebrate Paleontology, 2020
The African Cichlidae Oreochromis (Alcolapia) and Oreochromis amphimelas can survive in extremely... more The African Cichlidae Oreochromis (Alcolapia) and Oreochromis amphimelas can survive in extremely alkaline environments and represent the only known modern alkaliphilic cichlid fish found in Africa. The presence of fossil cichlids from the Miocene of central Kenya (Tugen Hills) that are morphologically similar to Oreochromis (Alcolapia) has been noted in previous works, but the conclusions remained tentative. The purpose of this study is to examine newly discovered fossil cichlids from the Tugen Hills and to compare their osteology with that of extant Oreochromis (Alcolapia). This is performed based on a comprehensive collection of comparative material, using microscopy and computed microtomography (μCT). We provide a revised diagnosis for the genus †Rebekkachromis, and revise its systematic relationships by assigning it to the Oreochromini (rather than to the Etiini). Two new species of †Rebekkachromis are described, i.e., †R. valyricus, sp. nov., and †R. vancouveringae, sp. nov., and a morphologically diverse assemblage of cooccurring †Rebekkachromis specimens is documented. Moreover, we found that †Rebekkachromis had three sensory canal pores (instead of four) on the lower arm of the preopercle, a feature that distinguishes both the modern Oreochromis (Alcolapia) and our fossil specimens from almost all other modern African cichlid fish. Our new data indicate that alkaliphile cichlids similar to Oreochromis (Alcolapia) were present in Central Kenya about 10-13 Ma ago and that the ability of African cichlid fishes to thrive in highly alkaline waters had already developed by that time.
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Zeitschrift der Deutschen Geologischen Gesellschaft, 1998
Hydrobiologia, 2020
Fossil cichlids from East Africa offer unique insights into the evolutionary history and ancient ... more Fossil cichlids from East Africa offer unique insights into the evolutionary history and ancient diversity of the family on the African continent. Here we present three fossil species of the extinct haplotilapiine cichlid †Baringochromis gen. nov. from the upper Miocene of the palaeolake Waril in Central Kenya, based on the analysis of a total of 78 articulated skeletons. †Baringochromis senutae sp. nov., †B. sonyii sp. nov. and †B. tallamae sp. nov. are superficially similar, but differ from each other in oral-tooth dentition and morphometric characters related to the head, dorsal fin base and body depth. These findings indicate that they represent an ancient small species flock. Possible modern analogues of palaeolake Waril and its species flock are discussed. The three species of †Baringochromis may have begun to subdivide their initial habitat by trophic differentiation. Possible sources of food could have been plant remains and insects, as their fossilized remains are known fro...
Journal of Zoological Systematics and Evolutionary Research, 2018
Among the species of Aphanius Nardo, 1827, Aphanius dispar (Ruppell, 1828) is the most common tax... more Among the species of Aphanius Nardo, 1827, Aphanius dispar (Ruppell, 1828) is the most common taxon and has long been viewed as representing a species group rather than a single species. This study provides comprehensive data on the phylogenetic relationships, morphology, and otoliths within the A. dispar species group, including the description of a new species. Our data demonstrate that the "true" A. dispar is restricted to the Red Sea drainages and that all other populations hitherto identified as A. dispar actually represent separate species. Four main clades are defined and named for the geographic areas in which the respective species of Aphanius occur. The oldest one is the "Red Sea clade," it comprises A. dispar. The "Dead Sea clade" is represented by A. richardsoni (Boulenger, 1907). It is sister to both the "Hormuzgan clade" in S Iran (containing A. hormuzensis sp. nov. and A. ginaonis (Holly, 1929)) and the "Persian Gulf & Gulf of Oman clade" (comprising A. stoliczkanus (Day, 1872)). The species separation within the A. dispar group is confirmed by the distinctive otolith morphology of each species. Moreover, we present a time-calibrated phylogeny (chronogram) for the A. dispar species group using dagger A. princeps (16-17 Mya) as a minimum age and the first appearance of dagger Prolebias (33-34 Mya) as a maximum age for the genus Aphanius. The evolution and historical biogeography routes are discussed based on the outcome of the chronogram and in the context of the geological and climatic history of the Near East in Pliocene-Pleistocene times.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 1996
Frontiers in Marine Science, 2015
Geological Magazine, 2015
The Miocene epoch was a time of major change in the East African Rift System (EARS) as forest hab... more The Miocene epoch was a time of major change in the East African Rift System (EARS) as forest habitats were transformed into grasslands and hominids appeared in the landscape. Here we provide new sedimentological and palynological data on the middle–upper Miocene Ngorora Formation (Tugen Hills, Central Kenya Rift, EARS), together with clay mineral characterizations, mammal finds and a description of the Ngorora fish Lagerstätte. Furthermore, we introduce a revised age ofc. 13.3 Ma for the onset of the Ngorora Formation. The older part of the Ngorora Formation (c. 13.3–12 Ma) records low-energy settings of lakes, floodplains and palaeosols, and evidence of analcime indicates that lakes were alkaline. The palynomorph spectrum consists of tree pollen (Juniperus, Podocarpus), Euphorbiaceae pollen (Acalypha, Croton) and herbaceous pollen of Poaceae and Asteraceae, suggestive of wooded grasslands or grassy woodlands. Alkaline lakes, floodplains and palaeosols continue upsection (c. 12–9 M...
International Journal of Earth Sciences, 2015
regionally diverse depositional environments, reflecting different water depths and co-varying en... more regionally diverse depositional environments, reflecting different water depths and co-varying environmental variables. Significant differences in abundance, diversity and species composition of the benthic foraminiferal assemblages demonstrate marginal-marine facies for Lutzingen, Haunsheim and Dattenhausen, nearshore facies for Hamlar 2 and shallow marine basin facies for Burgau. The characteristic lower Ottnangian benthic foraminiferal species exhibit restricted ecological tolerances. Hence, the absence or scarcity of these species in nearshore to marginal-marine deposits has no stratigraphic significance. The presence of two sedimentation cycles in the western German Molasse Basin alone may have resulted from the interplay of regional tectonics and basin development that have led to different rates of subsidence and sedimentation in the western and eastern sectors of the German Molasse Basin.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 2015
Zeitschrift der Deutschen Gesellschaft für Geowissenschaften, 2009
ABSTRACT The Pfander ridge east of Lake Constance (Southwest Germany) is composed of clastic sedi... more ABSTRACT The Pfander ridge east of Lake Constance (Southwest Germany) is composed of clastic sediments of the Lower Freshwater Molasse, the Upper Marine Molasse and the Upper Freshwater Molasse. Here we present a sedimentological and sequence stratigraphical study on the deltaic deposits of the Upper Marine Molasse that formed during the Eggenburgian/Ottnangian transgression (Lower Miocene) in front of the alluvial Pfander Fan. Specifically, we focus on the deltaic succession to the Northeast of the talus centre. Within this we investigated four sections, up to 400 m thick, in the area between Bregenz (Vorarlberg) and Weiler (Allgau). Four sedimentological units were defined: (1) the "basal" conglomerate, (2) the monotonous "zone of glauconitic sandstones", (3) the heterogenous "zone of the delta facies" with sandstones, thin marl layers and conglomerates, (4) the "zone of marls and fine-grained sandstones". The sections display, from northeast to southwest, a successive change from a distal shallow marine environment with no or very little influence from the Pfander Fan (Rothenbach and Kesselbach sections) to a proximal shallow marine environment with strong deltaic influences (Huberbach and Leckenbach sections). We suggest five base level cycles forming two transgressive-regressive sequences for the Upper Marine Molasse. The lower sequence (base level cycles I to III) is correlated with the Eggenburgian, its highstand systems tract is represented by deltaic sediments (base level cycles II and III). The upper sequence, for which we assume an Ottnangian age, can be subdivided into two base level cycles (IV and V). They probably can be correlated with the two known transgressive-regressive cycles of the Ottnangian in the southwestern German part of the Molasse Basin.
Scientia Marina, 2013
Inter-population differences in otolith shape, morphology and chemistry have been used effectivel... more Inter-population differences in otolith shape, morphology and chemistry have been used effectively as indicators for stock assessment or for recognizing environmental adaptation in fishes. However, the precise parameters that affect otolith morphology remain incompletely understood. Here we provide the first direct support for the hypothesis that inter-population differences in otolith morphology are genetically encoded. The study is based on otolith morphology and two mitochondrial markers (D-loop, 16S rRNA) of three natural populations of Aphanius fasciatus (Teleostei: Cyprinodontidae) from Southeast Tunisia. Otolith and genetic data yielded congruent tree topologies. Divergence of populations likely results from isolation events in the course of the Pleistocene sea level drops. We propose that otolith morphology is a valuable tool for resolving genetic diversity also within other teleost species, which may be important for ecosystem management and conservation of genetic diversity. As reconstructions of ancient teleost fish faunas are often solely based on fossil otoliths, our discoveries may also lead to a new approach to research in palaeontology.
Palaeontology, 2004
Six charophyte, 13 mollusc, four ostracod and nine ®sh otolith taxa are taxonomically described, ... more Six charophyte, 13 mollusc, four ostracod and nine ®sh otolith taxa are taxonomically described, and one fruit, one seed and two foraminiferal taxa are brie¯y noted from the Lower Cyrena Beds and the Lower Coloured Molasse of the Sindelsdorf section near Penzberg (approximately 50 km south of Munich). Our palaeoecological and lithological data from the Lower Cyrena Beds suggest a delta plain with lagoons, estuaries, slowly¯owing rivers, lakes and swamps. Faunal and¯oral elements of the Lower Coloured Molasse indicate lacustrine environments. The gastropod Tympanotonos and the tropical to subtropical ®sh fauna (Eleotridae, Ambassidae and Cyprinodontidae) suggest a warm, at least subtropical climate. Furthermore, Tympanotonos suggests comparisons with Recent molluscan faunas of the mangrove swamps of the West African coast, and thus hints at mangrove vegetation bordering the coasts of the Upper Bavarian Molasse Sea. A biostratigraphical classi®cation for the Oligocene Molasse deposits of the Penzberg Syncline is established for the ®rst time based on otoliths and charophytes. The Lower Cyrena Beds are attributed to the newly de®ned otolith zone OT-O1/2 and probably correspond to the oldest part of the Chara microcera Zone. The lowermost part of the Lower Coloured Molasse can be correlated both with otolith zone OT-O2 and the Chara microcera Zone. The Sindelsdorf section lies within the Rupelian±Chattian transition zone and thus the chronostratigraphic age is approximately 29±28 Ma.
Molecular Phylogenetics and Evolution
Here we explain why the species name Aphaniops hormuzensis (Teimori, Esmaeili, Hamidan, Reichenba... more Here we explain why the species name Aphaniops hormuzensis (Teimori, Esmaeili, Hamidan, Reichenbacher, 2018) should be considered as valid. As a consequence, the species name Aphaniops teimorii Freyhof and Yogurtcuoglu, 2020 should be treated as a junior synonym of A. hormuzensis .
Palaeogeography, Palaeoclimatology, Palaeoecology, 2021
Abstract The North Alpine Foreland Basin (NAFB) comprises one of the most complete sedimentary re... more Abstract The North Alpine Foreland Basin (NAFB) comprises one of the most complete sedimentary records of the Oligocene and Miocene. Driven by global sea-level fluctuations, vast sedimentary influx and tectonic movement. The locality of Unterrudling near Eferding (Upper Austria) exposes the largest succession of sedimentary deposits from the late Oligocene in the eastern NAFB. Additionally, this section shows the facies transition from the shallow-water Linz-Melk Formation to the deep-water Eferding Formation. In this work, the fossil fauna and flora of the Eferding Formation as well as its lithology are re-evaluated using a multidisciplinary approach to gain new insights into the palaeoenvironment, palaeoclimate, and palaeoecology. A transgressive sequence is documented using sedimentological and ichnological data. Furthermore, a correlation to the late Chattian transgressive Ch-3 sequence is suggested. The impact of rising sea level on marine biota is shown in detail by analysing various groups (Bivalvia, Echinodermata, Anthozoa, Foraminifera, Chondrichthyes, Osteichthyes), with several newly reported species from the Eferding Formation. Moreover, washed in plant material was analysed for the interpretation of the terrestrial climate indicating mainly humid subtropical conditions. Finally, the presence of phosphatic nodules indicates eutrophication on the shelf environment and the possibility of upwelling currents.
Journal of Vertebrate Paleontology, 2020
The African Cichlidae Oreochromis (Alcolapia) and Oreochromis amphimelas can survive in extremely... more The African Cichlidae Oreochromis (Alcolapia) and Oreochromis amphimelas can survive in extremely alkaline environments and represent the only known modern alkaliphilic cichlid fish found in Africa. The presence of fossil cichlids from the Miocene of central Kenya (Tugen Hills) that are morphologically similar to Oreochromis (Alcolapia) has been noted in previous works, but the conclusions remained tentative. The purpose of this study is to examine newly discovered fossil cichlids from the Tugen Hills and to compare their osteology with that of extant Oreochromis (Alcolapia). This is performed based on a comprehensive collection of comparative material, using microscopy and computed microtomography (μCT). We provide a revised diagnosis for the genus †Rebekkachromis, and revise its systematic relationships by assigning it to the Oreochromini (rather than to the Etiini). Two new species of †Rebekkachromis are described, i.e., †R. valyricus, sp. nov., and †R. vancouveringae, sp. nov., and a morphologically diverse assemblage of cooccurring †Rebekkachromis specimens is documented. Moreover, we found that †Rebekkachromis had three sensory canal pores (instead of four) on the lower arm of the preopercle, a feature that distinguishes both the modern Oreochromis (Alcolapia) and our fossil specimens from almost all other modern African cichlid fish. Our new data indicate that alkaliphile cichlids similar to Oreochromis (Alcolapia) were present in Central Kenya about 10-13 Ma ago and that the ability of African cichlid fishes to thrive in highly alkaline waters had already developed by that time.
[
Zeitschrift der Deutschen Geologischen Gesellschaft, 1998
Hydrobiologia, 2020
Fossil cichlids from East Africa offer unique insights into the evolutionary history and ancient ... more Fossil cichlids from East Africa offer unique insights into the evolutionary history and ancient diversity of the family on the African continent. Here we present three fossil species of the extinct haplotilapiine cichlid †Baringochromis gen. nov. from the upper Miocene of the palaeolake Waril in Central Kenya, based on the analysis of a total of 78 articulated skeletons. †Baringochromis senutae sp. nov., †B. sonyii sp. nov. and †B. tallamae sp. nov. are superficially similar, but differ from each other in oral-tooth dentition and morphometric characters related to the head, dorsal fin base and body depth. These findings indicate that they represent an ancient small species flock. Possible modern analogues of palaeolake Waril and its species flock are discussed. The three species of †Baringochromis may have begun to subdivide their initial habitat by trophic differentiation. Possible sources of food could have been plant remains and insects, as their fossilized remains are known fro...
Journal of Zoological Systematics and Evolutionary Research, 2018
Among the species of Aphanius Nardo, 1827, Aphanius dispar (Ruppell, 1828) is the most common tax... more Among the species of Aphanius Nardo, 1827, Aphanius dispar (Ruppell, 1828) is the most common taxon and has long been viewed as representing a species group rather than a single species. This study provides comprehensive data on the phylogenetic relationships, morphology, and otoliths within the A. dispar species group, including the description of a new species. Our data demonstrate that the "true" A. dispar is restricted to the Red Sea drainages and that all other populations hitherto identified as A. dispar actually represent separate species. Four main clades are defined and named for the geographic areas in which the respective species of Aphanius occur. The oldest one is the "Red Sea clade," it comprises A. dispar. The "Dead Sea clade" is represented by A. richardsoni (Boulenger, 1907). It is sister to both the "Hormuzgan clade" in S Iran (containing A. hormuzensis sp. nov. and A. ginaonis (Holly, 1929)) and the "Persian Gulf & Gulf of Oman clade" (comprising A. stoliczkanus (Day, 1872)). The species separation within the A. dispar group is confirmed by the distinctive otolith morphology of each species. Moreover, we present a time-calibrated phylogeny (chronogram) for the A. dispar species group using dagger A. princeps (16-17 Mya) as a minimum age and the first appearance of dagger Prolebias (33-34 Mya) as a maximum age for the genus Aphanius. The evolution and historical biogeography routes are discussed based on the outcome of the chronogram and in the context of the geological and climatic history of the Near East in Pliocene-Pleistocene times.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 1996
Frontiers in Marine Science, 2015
Geological Magazine, 2015
The Miocene epoch was a time of major change in the East African Rift System (EARS) as forest hab... more The Miocene epoch was a time of major change in the East African Rift System (EARS) as forest habitats were transformed into grasslands and hominids appeared in the landscape. Here we provide new sedimentological and palynological data on the middle–upper Miocene Ngorora Formation (Tugen Hills, Central Kenya Rift, EARS), together with clay mineral characterizations, mammal finds and a description of the Ngorora fish Lagerstätte. Furthermore, we introduce a revised age ofc. 13.3 Ma for the onset of the Ngorora Formation. The older part of the Ngorora Formation (c. 13.3–12 Ma) records low-energy settings of lakes, floodplains and palaeosols, and evidence of analcime indicates that lakes were alkaline. The palynomorph spectrum consists of tree pollen (Juniperus, Podocarpus), Euphorbiaceae pollen (Acalypha, Croton) and herbaceous pollen of Poaceae and Asteraceae, suggestive of wooded grasslands or grassy woodlands. Alkaline lakes, floodplains and palaeosols continue upsection (c. 12–9 M...
International Journal of Earth Sciences, 2015
regionally diverse depositional environments, reflecting different water depths and co-varying en... more regionally diverse depositional environments, reflecting different water depths and co-varying environmental variables. Significant differences in abundance, diversity and species composition of the benthic foraminiferal assemblages demonstrate marginal-marine facies for Lutzingen, Haunsheim and Dattenhausen, nearshore facies for Hamlar 2 and shallow marine basin facies for Burgau. The characteristic lower Ottnangian benthic foraminiferal species exhibit restricted ecological tolerances. Hence, the absence or scarcity of these species in nearshore to marginal-marine deposits has no stratigraphic significance. The presence of two sedimentation cycles in the western German Molasse Basin alone may have resulted from the interplay of regional tectonics and basin development that have led to different rates of subsidence and sedimentation in the western and eastern sectors of the German Molasse Basin.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 2015
Zeitschrift der Deutschen Gesellschaft für Geowissenschaften, 2009
ABSTRACT The Pfander ridge east of Lake Constance (Southwest Germany) is composed of clastic sedi... more ABSTRACT The Pfander ridge east of Lake Constance (Southwest Germany) is composed of clastic sediments of the Lower Freshwater Molasse, the Upper Marine Molasse and the Upper Freshwater Molasse. Here we present a sedimentological and sequence stratigraphical study on the deltaic deposits of the Upper Marine Molasse that formed during the Eggenburgian/Ottnangian transgression (Lower Miocene) in front of the alluvial Pfander Fan. Specifically, we focus on the deltaic succession to the Northeast of the talus centre. Within this we investigated four sections, up to 400 m thick, in the area between Bregenz (Vorarlberg) and Weiler (Allgau). Four sedimentological units were defined: (1) the "basal" conglomerate, (2) the monotonous "zone of glauconitic sandstones", (3) the heterogenous "zone of the delta facies" with sandstones, thin marl layers and conglomerates, (4) the "zone of marls and fine-grained sandstones". The sections display, from northeast to southwest, a successive change from a distal shallow marine environment with no or very little influence from the Pfander Fan (Rothenbach and Kesselbach sections) to a proximal shallow marine environment with strong deltaic influences (Huberbach and Leckenbach sections). We suggest five base level cycles forming two transgressive-regressive sequences for the Upper Marine Molasse. The lower sequence (base level cycles I to III) is correlated with the Eggenburgian, its highstand systems tract is represented by deltaic sediments (base level cycles II and III). The upper sequence, for which we assume an Ottnangian age, can be subdivided into two base level cycles (IV and V). They probably can be correlated with the two known transgressive-regressive cycles of the Ottnangian in the southwestern German part of the Molasse Basin.
Scientia Marina, 2013
Inter-population differences in otolith shape, morphology and chemistry have been used effectivel... more Inter-population differences in otolith shape, morphology and chemistry have been used effectively as indicators for stock assessment or for recognizing environmental adaptation in fishes. However, the precise parameters that affect otolith morphology remain incompletely understood. Here we provide the first direct support for the hypothesis that inter-population differences in otolith morphology are genetically encoded. The study is based on otolith morphology and two mitochondrial markers (D-loop, 16S rRNA) of three natural populations of Aphanius fasciatus (Teleostei: Cyprinodontidae) from Southeast Tunisia. Otolith and genetic data yielded congruent tree topologies. Divergence of populations likely results from isolation events in the course of the Pleistocene sea level drops. We propose that otolith morphology is a valuable tool for resolving genetic diversity also within other teleost species, which may be important for ecosystem management and conservation of genetic diversity. As reconstructions of ancient teleost fish faunas are often solely based on fossil otoliths, our discoveries may also lead to a new approach to research in palaeontology.
Palaeontology, 2004
Six charophyte, 13 mollusc, four ostracod and nine ®sh otolith taxa are taxonomically described, ... more Six charophyte, 13 mollusc, four ostracod and nine ®sh otolith taxa are taxonomically described, and one fruit, one seed and two foraminiferal taxa are brie¯y noted from the Lower Cyrena Beds and the Lower Coloured Molasse of the Sindelsdorf section near Penzberg (approximately 50 km south of Munich). Our palaeoecological and lithological data from the Lower Cyrena Beds suggest a delta plain with lagoons, estuaries, slowly¯owing rivers, lakes and swamps. Faunal and¯oral elements of the Lower Coloured Molasse indicate lacustrine environments. The gastropod Tympanotonos and the tropical to subtropical ®sh fauna (Eleotridae, Ambassidae and Cyprinodontidae) suggest a warm, at least subtropical climate. Furthermore, Tympanotonos suggests comparisons with Recent molluscan faunas of the mangrove swamps of the West African coast, and thus hints at mangrove vegetation bordering the coasts of the Upper Bavarian Molasse Sea. A biostratigraphical classi®cation for the Oligocene Molasse deposits of the Penzberg Syncline is established for the ®rst time based on otoliths and charophytes. The Lower Cyrena Beds are attributed to the newly de®ned otolith zone OT-O1/2 and probably correspond to the oldest part of the Chara microcera Zone. The lowermost part of the Lower Coloured Molasse can be correlated both with otolith zone OT-O2 and the Chara microcera Zone. The Sindelsdorf section lies within the Rupelian±Chattian transition zone and thus the chronostratigraphic age is approximately 29±28 Ma.