scholarly journals Refining the marine reptile turnover at the Early–Middle Jurassic transition

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10647
Author(s):  
Valentin Fischer ◽  
Robert Weis ◽  
Ben Thuy
Keyword(s):  
Middle Jurassic ◽  
Fossil Record ◽  
Late Jurassic ◽  
Western Europe ◽  
Marine Ecosystems ◽  
Taxonomic Composition ◽  
Restricted Area ◽  
Marine Reptile ◽  
Geological Formations ◽  
Geological Period

Even though a handful of long-lived reptilian clades dominated Mesozoic marine ecosystems, several biotic turnovers drastically changed the taxonomic composition of these communities. A seemingly slow paced, within-geological period turnover took place across the Early–Middle Jurassic transition. This turnover saw the demise of early neoichthyosaurians, rhomaleosaurid plesiosaurians and early plesiosauroids in favour of ophthalmosaurid ichthyosaurians and cryptoclidid and pliosaurid plesiosaurians, clades that will dominate the Late Jurassic and, for two of them, the entire Early Cretaceous as well. The fossil record of this turnover is however extremely poor and this change of dominance appears to be spread across the entire middle Toarcian–Bathonian interval. We describe a series of ichthyosaurian and plesiosaurian specimens from successive geological formations in Luxembourg and Belgium that detail the evolution of marine reptile assemblages across the Early–Middle Jurassic transition within a single area, the Belgo–Luxembourgian sub-basin. These fossils reveal the continuing dominance of large rhomaleosaurid plesiosaurians, microcleidid plesiosaurians and Temnodontosaurus-like ichthyosaurians up to the latest Toarcian, indicating that the structuration of the upper tier of Western Europe marine ecosystems remained essentially constant up to the very end of the Early Jurassic. These fossils also suddenly record ophthalmosaurid ichthyosaurians and cryptoclidid plesiosaurians by the early Bajocian. These results from a geographically-restricted area provide a clearer picture of the shape of the marine reptile turnover occurring at the early–Middle Jurassic transition. This event appears restricted to the sole Aalenian stage, reducing the uncertainty of its duration, at least for ichthyosaurians and plesiosaurians, to 4 instead of 14 million years.

scholarly journals A review of the fossil record of non-baenid turtles of the clade Paracryptodira

2019 ◽  
Author(s):  
Walter G. Joyce ◽  
Jérémy Anquetin
Keyword(s):  
North America ◽  
Middle Jurassic ◽  
Fossil Record ◽  
Late Jurassic ◽  
Feeding Strategies ◽  
Aquatic Environments ◽  
Taxonomic Review ◽  
Nomina Invalida ◽  
Nomina Dubia

The fossil record of non-baenid paracryptodires ranges from the Late Jurassic (Kimmeridgian) tothe Paleocene of North America and Europe only. Earlier remains may be present as early as the Middle Jurassic (Bathonian). Only a single dispersal event is documented between the two continents following their breakup during the Cretaceous in the form of the appearance of the Compsemys lineage in the Paleocene of France. Non-baenid paracryptodires were restricted to freshwater aquatic environments, but display adaptations to diverse feeding strategies consistent with generalist, gape-and-suction, and hypercarnivorous feeding. Current phylogenies recognize two species rich subclades within Paracryptodira, Baenidae and Pleurosternidae, which jointly form the clade Baenoidea. A taxonomic review of non-baenid paracryptodires concludes that of 34 named taxa, 11 are nomina valida, 15 nomina invalida, and 8 nomina dubia.

First record ofOphthalmosaurus(Reptilia: Ichthyosauria) from the Tithonian (Upper Jurassic) of Mexico

2010 ◽  
Vol 84 (1) ◽  
pp. 149-155 ◽  
Author(s):  
Marie-Céline Buchy
Keyword(s):  
Middle Jurassic ◽  
Late Jurassic ◽  
Field Work ◽  
First Record ◽  
Upper Jurassic ◽  
Marine Transgression ◽  
North East ◽  
The Pacific ◽  
Invertebrate Assemblages ◽  
Marine Reptile

From the Middle Jurassic on, the Tethys basin opened westward; the existence of a Carribean corridor linking the European and Pacific realms now appears well supported by comparison of marine reptile assemblages (e.g., Gasparini and Fernández, 1997, 2005; Gasparini et al., 2000; Fernández and Iturralde-Vinent, 2000; Gasparini and Iturralde-Vinent, 2001, 2006; Gasparini et al., 2002). Marine transgression in Mexico began during the Callovian, as evidenced by the evaporites of the Minas Viejas Fm. However, microfossils and invertebrate assemblages indicate that the Mexican Gulf remained isolated from both the European Archipelago and the Pacific, at least temporarily, until the middle Berriasian; the Florida uplift and southward movement of Yucatan were proposed as possibly forming a barrier (Salvador et al., 1993; Adatte et al., 1994, 1996; Goldhammer, 1999; Goldhammer and Johnston, 2001; Gasparini and Iturralde-Vinent, 2006). After almost a decade of field work and examination of collections, the Late Jurassic marine reptile assemblage of north-east Mexico confirms the conclusions drawn from microfossils and invertebrates. Poorly diagnostic ichthyosaur remains, with various thalattosuchians, numerically dominate the assemblage. Sauropterygians are rare, mainly represented by large pliosaurids of unclear affinities, a few vertebrae attributed to elasmosaurids, and a unique cryptoclidid. Turtles are yet to be reported (Frey et al., 2002; Buchy et al., 2003, 2005b, 2006a–d; Buchy, 2007, 2008a, b; material currently under study).

scholarly journals A turiasaurian sauropod dinosaur from the Early Cretaceous Wealden Supergroup of the United Kingdom

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6348
Author(s):  
Philip D. Mannion
Keyword(s):  
Early Cretaceous ◽  
Middle Jurassic ◽  
Late Jurassic ◽  
Western Europe ◽  
Phylogenetic Analyses ◽  
Neural Spine ◽  
Faunal Turnover ◽  
The United Kingdom ◽  
The Usa ◽  
The Uk

The Jurassic/Cretaceous (J/K) boundary, 145 million years ago, has long been recognised as an extinction event or faunal turnover for sauropod dinosaurs, with many ‘basal’ lineages disappearing. However, recently, a number of ‘extinct’ groups have been recognised in the Early Cretaceous, including diplodocids in Gondwana, and non-titanosauriform macronarians in Laurasia. Turiasauria, a clade of non-neosauropod eusauropods, was originally thought to have been restricted to the Late Jurassic of western Europe. However, its distribution has recently been extended to the Late Jurassic of Tanzania (Tendaguria tanzaniensis), as well as to the Early Cretaceous of the USA (Mierasaurus bobyoungi and Moabosaurus utahensis), demonstrating the survival of another ‘basal’ clade across the J/K boundary. Teeth from the Middle Jurassic–Early Cretaceous of western Europe and North Africa have also tentatively been attributed to turiasaurs, whilst recent phylogenetic analyses recovered Late Jurassic taxa from Argentina and China as further members of Turiasauria. Here, an anterior dorsal centrum and neural arch (both NHMUK 1871) from the Early Cretaceous Wealden Supergroup of the UK are described for the first time. NHMUK 1871 shares several synapomorphies with Turiasauria, especially the turiasaurs Moabosaurus and Tendaguria, including: (1) a strongly dorsoventrally compressed centrum; (2) the retention of prominent epipophyses; and (3) an extremely low, non-bifid neural spine. NHMUK 1871 therefore represents the first postcranial evidence for Turiasauria from European deposits of Early Cretaceous age. Although turiasaurs show clear heterodont dentition, only broad, characteristically ‘heart’-shaped teeth can currently be attributed to Turiasauria with confidence. As such, several putative turiasaur occurrences based on isolated teeth from Europe, as well as the Middle Jurassic and Early Cretaceous of Africa, cannot be confidently referred to Turiasauria. Unequivocal evidence for turiasaurs is therefore restricted to the late Middle Jurassic–Early Cretaceous of western Europe, the Late Jurassic of Tanzania, and the late Early Cretaceous of the USA, although remains from elsewhere might ultimately demonstrate that the group had a near-global distribution.

scholarly journals Peculiar macrophagous adaptations in a new Cretaceous pliosaurid

2015 ◽  
Vol 2 (12) ◽  
pp. 150552 ◽  
Author(s):  
Valentin Fischer ◽  
Maxim S. Arkhangelsky ◽  
Ilya M. Stenshin ◽  
Gleb N. Uspensky ◽  
Nikolay G. Zverkov ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Fossil Record ◽  
Late Jurassic ◽  
Phylogenetic Analyses ◽  
Consensus Methods ◽  
Ancestral State ◽  
Ecological Diversity ◽  
Apex Predator ◽  
State Reconstruction ◽  
Marine Reptile

During the Middle and Late Jurassic, pliosaurid plesiosaurs evolved gigantic body size and a series of craniodental adaptations that have been linked to the occupation of an apex predator niche. Cretaceous pliosaurids (i.e. Brachaucheninae) depart from this morphology, being slightly smaller and lacking the macrophagous adaptations seen in earlier forms. However, the fossil record of Early Cretaceous pliosaurids is poor, concealing the evolution and ecological diversity of the group. Here, we report a new pliosaurid from the Late Hauterivian (Early Cretaceous) of Russia. Phylogenetic analyses using reduced consensus methods recover it as the basalmost brachauchenine. This pliosaurid is smaller than other derived pliosaurids, has tooth alveoli clustered in pairs and possesses trihedral teeth with complex serrated carinae. Maximum-likelihood ancestral state reconstruction suggests early brachauchenines retained trihedral teeth from their ancestors, but modified this feature in a unique way, convergent with macrophagous archosaurs or sphenacodontoids. Our findings indicate that Early Cretaceous marine reptile teeth with serrated carinae cannot be unequivocally assigned to metriorhynchoid crocodylomorphs. Furthermore, they extend the known diversity of dental adaptations seen in Sauropterygia, the longest lived clade of marine tetrapods.

First rove beetles from the Jurassic Talbragar Fish Bed of Australia (Coleoptera, Staphylinidae)

2013 ◽  
Vol 87 (4) ◽  
pp. 650-656 ◽  
Author(s):  
Chen-Yang Cai ◽  
Evgeny V. Yan ◽  
Robert Beattie ◽  
Bo Wang ◽  
Di-Ying Huang
Keyword(s):  
Middle Jurassic ◽  
Fossil Record ◽  
Late Jurassic ◽  
New South ◽  
New South Wales ◽  
The Other ◽  
Rove Beetles ◽  
Rove Beetle ◽  
South Wales ◽  
Distinct Features

The first two rove beetle fossils discovered from the Late Jurassic Talbragar Fish Bed in New South Wales, Australia are described and illustrated.Juroglypholoma talbragarensen. sp. is the second fossil record for one of the smallest and latest recognized staphylinid subfamily Glypholomatinae. The other staphylinid,Protachinus minorn. gen. n. sp., is an unusual member of extant subfamily Tachyporinae (tribe Tachyporini). It significantly retains several distinct features, including entire epistomal suture, and abdominal tergites III–VI each with a pair of basolateral ridges. The discovery of a new glypholomatine in Australia, together with recently reported one from the Middle Jurassic Daohugou biota of China, suggests the subfamily Glypholomatinae was probably much more widespread in the Jurassic than previously thought.

Radiolarian assemblages of Middle and Late Jurassic to early Late Cretaceous (Cenomanian) ages from an olistolith record pelagic deposition within the Bornova Flysch Zone in western Turkey

2012 ◽  
Vol 183 (4) ◽  
pp. 307-318 ◽  
Author(s):  
Ugur Kagan Tekin ◽  
M. Cemal Göncüoglu ◽  
Seda Uzuncimen
Keyword(s):  
Late Cretaceous ◽  
Middle Jurassic ◽  
Late Jurassic ◽  
Western Turkey ◽  
Oceanic Basin ◽  
Platform Margin ◽  
Lowermost Part ◽  
Early Late ◽  
Radiolarian Assemblages

Abstract The Bornova Flysch Zone (BFZ) in NW Anatolia comprises several olistoliths or tectonic slivers, representing various parts of the Izmir-Ankara ocean. Radiolarian assemblages extracted from one of the olistoliths of the BFZ, cropping out along the Sögütlü section, to the NE Manisa city, were studied in detail. The lowermost part of the section contains latest Bajocian – early Callovian radiolarian taxa, followed by radiolarian assemblages indicating Late Jurassic to early Late Cretaceous (Cenomanian) ages. Previous studies reveal that the Izmir-Ankara oceanic basin was initially opened during late Ladinian – early Carnian. The new radiolarian data obtained from this olistolith reveals that relatively condensed, and possibly more or less continuous, pelagic sedimentation took place during the late Middle Jurassic to early Late Cretaceous in a non-volcanic oceanic basin closer to the Tauride-Anatolide platform margin.

scholarly journals The first Mares Conference on Marine Ecosystems Health and Conservation 2014: key messages and outcomes

2015 ◽  
Author(s):  
Tim Deprez ◽  
Magda Vincx ◽  
Adelino V.M. Canario ◽  
Karim Erzini ◽  
Katherine Brownlie
Keyword(s):  
Climate Change ◽  
Biological Invasions ◽  
Salt Marshes ◽  
Marine Mammals ◽  
Climate Adaptation ◽  
Marine Ecosystems ◽  
Taxonomic Composition ◽  
Marine Biodiversity ◽  
Intergovernmental Panel ◽  
Ocean Noise

The first Mares Conference on Marine Ecosystems Health and Conservation was a successful event organized by the MARES doctoral programme bringing together over 150 researchers in Olhão, Portugal from November 17th to 21st 2014. The conference was opened by Prof. Dr. Hans-Otto Pörtner, whose keynote address focused on a sectoral analysis by the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5) on the impacts of climate change on the world’s oceans. The first session on “Future oceans” was opened with a talk by Dr. Frank Melzner highlighting the problems calcifying invertebrates face in the warmer, more acidic and hypoxic waters. Other presenters dealt with changing global diversity patterns, ocean acidification, and the loss the genetic diversity. The second session on “Natural resources” was opened by Dr. Rainer Froese, who focused on whether or not the oceans can feed humanity. This talk introduced other contributions in the session, dealing with fisheries issues and Marine Protected Areas, as well as problems with proper identifications of species used for economic purposes. “Biodiversity effects” was the scope of the third session opened by a talk on oxygenation and marine biodiversity challenges in the 21st Century by Prof. Lisa Levin. Rapid ocean deoxygenation is a process which is currently less investigated but which has considerable effects on body size, taxonomic composition, habitat heterogeneity, and nutrient cycling. The following presentations focused on other factors having a strong effect on marine biodiversity, ranging from the harvesting of algae to the fragmentation of ecosystems. The fourth session addressed “Biological invasions”. Dr. Gregory Ruiz discussed biological invasions in North American marine ecosystems and the need for constant monitoring, and the use of a dynamic and multi-vector approach. Problems with invasive species in European waters were addressed with examples from the Baltic Sea, the North Sea, and the Mediterranean Sea. The fifth session on “Ocean Noise” was opened by Prof. Peter Tyack with a talk on the effects of anthropogenic sound on marine mammals. Although ocean noise issues are often linked to marine mammals, the effects of sound related to marine constructions on fish behaviour, nicely illustrated that ocean noise is a factor with a much broader impact than expected. The last session of the first Mares Conference dealt with “Habitat loss”. Dr. Michael Beck focused on this topic with his talk on ‘Building Coastal Resilience for Climate Adaptation and Risk Reduction’. Talks in the session ranged from the use of telemetry as a tool to monitor species in changed habitats, to cases dealing with sea level rise related problems in for example salt-marshes. The first Mares Conference offered a broad range of oral and poster presentations, as well as digital presentations. The poster and digital object presentations included over 100 contributions.

Implications for the study of fossil Asteroidea (Echinodermata) of new genera and species from the Eocene of Florida

2009 ◽  
Vol 83 (4) ◽  
pp. 562-574 ◽  
Author(s):  
Daniel B. Blake ◽  
Roger W. Portell
Keyword(s):  
Family History ◽  
New Taxa ◽  
Middle Jurassic ◽  
Fossil Record ◽  
New Genera ◽  
Crown Group ◽  
Marine Communities ◽  
The Family ◽  
Ocala Limestone

Oyenaster oblidus, Ocalaster timucum, and Ocalaster seloyi are new genera and species of the family Goniasteridae (Asteroidea) described from the Eocene Ocala Limestone of Florida. Although the fossil record of asteroids is sketchy, goniasterids appear to have been important contributors to marine communities since at least the Middle Jurassic. Similarities between living goniasterids and their fossil precursors indicate that plesiomorphy and convergence have been important in family history, and as a result, taxonomic interpretation is challenging. Even partial fossil goniasterids are rare, forcing systematists to rely heavily on isolated marginal ossicles, although some authors have expressed the need for caution. Building around three new taxa, we suggest that broader approaches can aid systematic interpretation of all crown-group asteroids. We also suggest that the inevitably idiosyncratic interpretations of marginal-based systematics can be partially tested using blind evaluations.

First records of Somalinautilus (Cephalopoda: Nautiloidea) from the Jurassic of Southern Germany – inferences for trans-provincial migrations

2020 ◽  
Vol 298 (2) ◽  
pp. 137-146
Author(s):  
Günter Schweigert
Keyword(s):  
Sea Level ◽  
Geographic Distribution ◽  
Middle Jurassic ◽  
Late Jurassic ◽  
Southern Germany ◽  
First Time ◽  
Lower Kimmeridgian ◽  
Lower Bathonian

The Late Jurassic nautiloid Somalinautilus antiquus (Dacqué, 1910), previously only known by the holotype from Lower Kimmeridgian strata of Ethiopia, is reported from the Lower Kimmeridgian (Platynota Zone) of Southern Germany. This unexpected record largely expands the known geographic distribution of this species. Another species of Somalinautilus, S. clavifer Tintant , 1994, is recorded for the first time from the Middle Jurassic (Lower Bathonian, Zigzag Zone) of Southern Germany. A short stratigraphic and palaeogeographic review of Somalinautilus occurrences is provided. Faunal migrations of nautiloids over large distances were probably triggered by sea- level highstands and/or palaeocurrents.

scholarly journals Paleobiogeographic significance of Famennian echinoderm faunas from northwestern China

1992 ◽  
Vol 6 ◽  
pp. 197-197
Author(s):  
C.G. Maples ◽  
J.A. Waters ◽  
N.G. Lane ◽  
Hou Hong-Fei
Keyword(s):  
Western Europe ◽  
Junggar Basin ◽  
Morphological Characters ◽  
Taxonomic Composition ◽  
Northwestern China ◽  
Republic Of China ◽  
Biogeographic Provinces ◽  
Global Cooling ◽  
Extinction Event ◽  
Migratory Pathway

A diverse (>200 specimens representing more than 20 taxa) Famennian echinoderm fauna has been collected from the Hongguleleng Formation, Junggar Basin, Xinjiang, Uygur Autonomous Region, Peoples Republic of China. Famennian faunas are relatively poorly known on a global basis, Famennian echinoderm faunas in general are very poorly known, and echinoderm faunas of any age from China are virtually unstudied. Echinoderms are highly endemic, which makes them relatively poor for global biostratigraphy, but excellent for use in biogeographic studies. Because Frasnian and Famennian faunas are noted for their general lack of endemism, echinoderms may be critical, sensitive indicators of Famennian biogeographic provinces. Preliminary analysis indicates that this Chinese Famennian echinoderm fauna is dominated by blastoids and inadunate, small-calyx camerate, and flexible crinoids, many of which show morphological characters that are intermediate in nature at higher classificatory levels between older Devonian and younger Carboniferous taxa. The taxonomic composition of this fauna clearly indicates that diversification and re-radiation in the aftermath of the Frasnian-Famennian extinction event was well underway before the close of the Famennian. The most similar faunas are from Famennian rocks of England and, possibly, Germany. Brachiopods, corals, and trilobites of this age also show similarities between northwestern China and western Europe. These two areas were high latitudinal and tropical, respectively, during deposition, therefore their similar composition may represent latitudinal contraction associated with global cooling or a nearshore migratory pathway between the two areas via Kazahkstan and Poland.

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