What Iberian dinosaurs reveal about the bridge said to exist between Gondwana and Laurasia in the Early Cretaceous

Abstract Some Cretaceous dinosaur taxa with a broad enough record on the continents of the northern hemisphere (Laurasia) or in the southern continents (Gondwana) have been interpreted as Laurasian or Gondwanan in origin. The occasional presence of these taxa outside Laurasia or Gondwana respectively has frequently been explained in terms of dispersal from their place of origin by means of land bridges that are indeterminate in location and character. One example of such a dispersal event is provided by the Early Cretaceous dinosaurs of Europe and Africa. Certain European taxa have been interpreted as having their origin in Gondwana. If we regard these presences common to both areas as being the result of a point of communication between Laurasia and western Gondwana or at least of sporadic flows in both directions during the Early Cretaceous, we may opt for dispersal as an explanation. It has been assumed that there was an intercontinental bridge between Africa and Europe passing through the archipelago of which Iberia formed a part. This interpretation emerged from the idea that such a bridge existed in the Late Jurassic, explaining the presence of similar ornithopod dinosaurs in Africa and Europe. However, from the end of the Early Jurassic a period of “rift” began on the southern Iberian margin, entailing the formation of a sedimentary furrow with pelagic sedimentation in what is known as the Subbetic zone. Moreover, the differences in the observed dinosaur fauna between western Gondwana and the Iberian Peninsula in the Neocomian can be explained as the result of endemism and regional extinctions. The archipelago that formed the Iberian plate was Laurasia’s closest continental mass to Gondwana during the Neocomian, yet there was still a separation of several hundred kilometres of open ocean without islands. Such a barrier would seem difficult for dinosaurs to overcome. As such, we lack proof of communication between the two supercontinents via Iberia during the Neocomian. The situation appears to change in the Barremian-Aptian transition. Some of the taxa present in the Hauterivian-Barremian of Europe are recorded in Gondwana from the Aptian onwards. This can possibly be explained in terms of the more complete record that exists, but it cannot be ruled out that a communication was established between Gondwana and Laurasia at the end of the Barremian. For the time being, we lack geological support for this bridge in Iberia, yet it might be located in Apulia, where there is a great development of shallow-shelf carbonates with dinosaur remains from the period in question.

Download Full-text

New multituberculate mammal from the Early Cretaceous of eastern North America

Canadian Journal of Earth Sciences ◽

10.1139/e2012-051 ◽

2013 ◽

Vol 50 (3) ◽

pp. 315-323 ◽

Cited By ~ 4

Author(s):

Richard L. Cifelli ◽

Cynthia L. Gordon ◽

Thomas R. Lipka

Keyword(s):

North America ◽

Iberian Peninsula ◽

Early Cretaceous ◽

North American ◽

Lower Cretaceous ◽

Late Jurassic ◽

Relative Length ◽

Central Position ◽

Eastern North America ◽

The North

Multituberculates, though among the most commonly encountered mammalian fossils of the Mesozoic, are poorly known from the North American Early Cretaceous, with only one taxon named to date. Herein we describe Argillomys marylandensis, gen. et sp. nov., from the Early Cretaceous of Maryland, based on an isolated M2. Argillomys represents the second mammal known from the Arundel Clay facies of the Patuxent Formation (Lower Cretaceous: Aptian). Though distinctive in its combination of characters (e.g., enamel ornamentation consisting of ribs and grooves only, cusp formula 2:4, presence of distinct cusp on anterobuccal ridge, enlargement of second cusp on buccal row, central position of ultimate cusp in lingual row, great relative length), the broader affinities of Argillomys cannot be established because of non-representation of the antemolar dentition. Based on lack of apomorphies commonly seen among Cimolodonta (e.g., three or more cusps present in buccal row, fusion of cusps in lingual row, cusps strongly pyramidal and separated by narrow grooves), we provisionally regard Argillomys as a multituberculate of “plagiaulacidan” grade. Intriguingly, it is comparable in certain respects to some unnamed Paulchoffatiidae, a family otherwise known from the Late Jurassic – Early Cretaceous of the Iberian Peninsula.

Download Full-text

Mesozoic Intracontinental Orogeny in the Tectonic History of the Kolyvan’– Tomsk Folded Zone (Southern Siberia): a Synthesis of Geological Data and results of Apatite Fission Track Analysis

Russian Geology and Geophysics ◽

10.2113/rgg20204172 ◽

2021 ◽

Vol 62 (9) ◽

pp. 1006-1020

Author(s):

F.I. Zhimulev ◽

E.V. Vetrov ◽

I.S. Novikov ◽

G. Van Ranst ◽

S. Nachtergaele ◽

...

Keyword(s):

Early Cretaceous ◽

Middle Jurassic ◽

Late Jurassic ◽

Fission Track ◽

Early Jurassic ◽

Late Triassic ◽

Apatite Fission Track ◽

History Of ◽

Paleozoic Rocks ◽

Orogenic Events

Abstract —The Kolyvan’–Tomsk folded zone (KTFZ) is a late Permian collisional orogen in the northwestern section of the Central Asian Orogenic Belt. The Mesozoic history of the KTFZ area includes Late Triassic–Early Jurassic and Late Jurassic–Early Cretaceous orogenic events. The earlier event produced narrow deep half-ramp basins filled with Early–Middle Jurassic molasse south of the KTFZ, and the later activity rejuvenated the Tomsk thrust fault, whereby the KTFZ Paleozoic rocks were thrust over the Early–Middle Jurassic basin sediments. The Mesozoic orogenic events induced erosion and the ensuing exposure of granitoids (Barlak complex) that were emplaced in a within-plate context after the Permian collisional orogeny. Both events were most likely associated with ocean closure, i.e., the Paleothetys Ocean in the Late Triassic–Early Jurassic and the Mongol–Okhotsk Ocean in the Late Jurassic–Early Cretaceous. The apatite fission track (AFT) ages of granitoids from the Ob’ complex in the KTFZ range between ~120 and 100 Ma (the Aptian and the Albian). The rocks with Early Cretaceous AFT ages were exhumed as a result of denudation and peneplanation of the Early Cretaceous orogeny, which produced a vast Late Cretaceous–Paleogene planation surface. The tectonic pattern of the two orogenic events, although being different in details, generally inherited the late Paleozoic primary collisional structure of the Kolyvan’–Tomsk zone.

Download Full-text

A new specimen of the theropod dinosaur Baryonyx from the early Cretaceous of Portugal and taxonomic validity of Suchosaurus

Zootaxa ◽

10.11646/zootaxa.2827.1.3 ◽

2011 ◽

Vol 2827 (1) ◽

pp. 54 ◽

Cited By ~ 22

Author(s):

OCTÁVIO MATEUS ◽

RICARDO ARAÚJO ◽

Carlos Natário ◽

RUI CASTANHINHA

Keyword(s):

Iberian Peninsula ◽

Early Cretaceous ◽

Late Jurassic ◽

Enamel Surface ◽

Tooth Root ◽

Theropod Dinosaur ◽

Incertae Sedis ◽

Caudal Vertebrae ◽

Nomina Dubia

Although the Late Jurassic of Portugal has provided abundant dinosaur fossils, material from the Early Cretaceous is scarce. This paper reports new cranial and postcranial material of the theropod dinosaur Baryonyx walkeri found in the Barremian (Papo Seco Formation) of Portugal. This specimen, found at Praia das Aguncheiras, Cabo Espichel, consists of a partial dentary, isolated teeth, pedal ungual, two calcanea, presacral and caudal vertebrae, fragmentary pubis, scapula, and rib fragments. It represents the most complete spinosaurid yet discovered in the Iberian Peninsula and the most complete dinosaur from the Early Cretaceous of Portugal. This specimen is confidently identified as a member of Baryonychinae due to the presence of conical teeth with flutes and denticles in a dentary rosette. The specimen ML1190 shares the following characteristics with Baryonyx walkeri: enamel surface with small (nearly vertical) wrinkles, variable denticle size along the carinae, 6–7 denticles per mm, wrinkles forming a 45 degree angle near the carinae, and tooth root longer than crown. In addition, dubious taxa based on teeth morphology such as Suchosaurus cultridens (Owen, 1840–1845), and Suchosaurus girardi (Sauvage 1897–98; Antunes & Mateus 2003) are discussed, based on comparisons with well-known material such as Baryonyx walkeri Charig & Milner, 1986. Suchosaurus cultridens and S. girardi are considered as nomina dubia due to the lack of diagnostic apomorphies, but both specimens are referred to Baryonychinae incertae sedis.

Download Full-text

A basal thunnosaurian from Iraq reveals disparate phylogenetic origins for Cretaceous ichthyosaurs

Biology Letters ◽

10.1098/rsbl.2013.0021 ◽

2013 ◽

Vol 9 (4) ◽

pp. 20130021 ◽

Cited By ~ 38

Author(s):

Valentin Fischer ◽

Robert M. Appleby ◽

Darren Naish ◽

Jeff Liston ◽

James B. Riding ◽

...

Keyword(s):

Middle East ◽

Early Cretaceous ◽

Late Jurassic ◽

Evolutionary History ◽

Early Jurassic ◽

Late Triassic ◽

Low Diversity ◽

History Of

Cretaceous ichthyosaurs have typically been considered a small, homogeneous assemblage sharing a common Late Jurassic ancestor. Their low diversity and disparity have been interpreted as indicative of a decline leading to their Cenomanian extinction. We describe the first post-Triassic ichthyosaur from the Middle East, Malawania anachronus gen. et sp. nov. from the Early Cretaceous of Iraq, and re-evaluate the evolutionary history of parvipelvian ichthyosaurs via phylogenetic and cladogenesis rate analyses. Malawania represents a basal grade in thunnosaurian evolution that arose during a major Late Triassic radiation event and was previously thought to have gone extinct during the Early Jurassic. Its pectoral morphology appears surprisingly archaic, retaining a forefin architecture similar to that of its Early Jurassic relatives. After the initial latest Triassic radiation of early thunnosaurians, two subsequent large radiations produced lineages with Cretaceous representatives, but the radiation events themselves are pre-Cretaceous. Cretaceous ichthyosaurs therefore include distantly related lineages, with contrasting evolutionary histories, and appear more diverse and disparate than previously supposed.

Download Full-text

Evolution of plant terpenoids on a ‘biotic ferry’

10.5194/egusphere-egu2020-7365 ◽

2020 ◽

Author(s):

Suryendu Dutta

Keyword(s):

Northern Hemisphere ◽

Early Cretaceous ◽

Late Jurassic ◽

Molecular Composition ◽

Indian Plate ◽

Western India ◽

Early Eocene ◽

Rain Forests ◽

Drastic Reduction ◽

Ca 50

Palaeogegraphic model suggests that the Indian plate was separated from Gondwana during Late Jurassic and started moving towards the northern hemisphere during the Early Cretaceous and remained as an island continent during the entire Cretaceous until it collided with Asia in Early Eocene at ca. 50 Ma. &#160;It is believed that many vertebrate groups may have originated in India or other Gondwanan land masses and were carried on the rafting Indian plate and finally dispersed &#8216;out of India&#8217; following the collision between India and Asia. However, the evolution of plants on the rafting continent is poorly documented.&#160;A brief outline on evolution of plant terpenoids from Permian to Eocene on the Indian continent will be discussed during the presentation. The Permian coals are characterized by tricyclic and teracyclic diterpenoids. The possible source of these compounds is extinct seed ferns.The molecular composition of Jurassic and early Cretaceous coals and sediments suggests that the vegetation was contributed by conifers (e.g. Arucariaceace, Podocarpaceae) during the period. Aromatic triterpenoids derived from angiosperms are detected in the sediments of Late Maastrichtian age. Drastic reduction of coniferous vegetation and proliferation of angiosperms in early Palaeogene are observed in the present study. The terpenoid signatures of early Palaeogene lignites suggest that the western India was covered by widespread thick closed rain forests dominated by family Dipterocarpaceae thriving under the influence of tropical climate.

Download Full-text

Thai amber: insights into early diatom history?

BSGF - Earth Sciences Bulletin ◽

10.1051/bsgf/2020028 ◽

2020 ◽

Vol 191 ◽

pp. 23

Author(s):

Vincent Girard ◽

Simona Saint Martin ◽

Eric Buffetaut ◽

Jean-Paul Saint Martin ◽

Didier Néraudeau ◽

...

Keyword(s):

Early Cretaceous ◽

Late Cretaceous ◽

Fossil Record ◽

Late Jurassic ◽

Molecular Data ◽

Early Jurassic ◽

Coastal Environments ◽

Potential Bias ◽

Fossil Evidence ◽

History Of

The origin of the diatoms still remains enigmatic. Their fossil record is scarce until the Late Cretaceous and great divergences exist between molecular data and the earliest fossil evidence. While molecular data indicate an origin during the Triassic or Early Jurassic, early fossil evidence is only from the Late Jurassic-Early Cretaceous. The discovery of diatoms in French mid-Cretaceous amber by the end of the 2000s already suggested a potential bias in the diatom fossil record as it made older many diatom lineages, the record of which hitherto began at the end of the Cretaceous. The Jurassic/Early Cretaceous fossil record of diatoms is extremely sparse and any new occurrence is important for retracing the evolutionary, palaeogeographical and palaeoenvironmental history of diatoms. Thai amber has yielded a new diatom specimen that has been attributed to the genus Hemiaulus. Fossil assemblages and sedimentological data indicate that Thai amber and its Hemiaulus specimen are Late Jurassic in age. This discovery represents the oldest hitherto known specimen of Hemiaulus and so extends the fossil record of the bipolar diatoms and of the genus Hemiaulus by several dozens of millions of years and brings closer the fossil evidence and molecular data (that estimated an origin of the bipolar diatoms about 150 Ma ago). It reinforces the hypothesis of a pre-Cretaceous fossil diatom records and also supports an origin of the diatoms in shallow coastal environments.

Download Full-text

U–Pb and K–Ar dates related to the timing of magmatism and deformation in the Cache Creek terrane and Quesnellia, southern British Columbia

Canadian Journal of Earth Sciences ◽

10.1139/e90-009 ◽

1990 ◽

Vol 27 (1) ◽

pp. 117-123 ◽

Cited By ~ 12

Author(s):

N. Mortimer ◽

P. van der Heyden ◽

R. L. Armstrong ◽

J. Harakal

Keyword(s):

British Columbia ◽

Early Cretaceous ◽

North American ◽

Late Jurassic ◽

Early Jurassic ◽

Early Permian ◽

Magmatic Arc ◽

Plutonic Complex ◽

Minimum Age ◽

Coast Plutonic Complex

U–Pb dating of zircon from the Guichon Creek batholith indicates an emplacement age of 210 ± 3 Ma. Comparison with previously published K–Ar (211–188 Ma) and Rb–Sr (205 and 196 Ma) dates reveals that intrusion, mineralization, cooling, and uplift of the batholith took some 20 Ma, spanning the Triassic–Jurassic boundary on the Decade of North American Geology (DNAG) time scale.The Mount Martley pluton and Tiffin Creek stock yield Late Jurassic dates of 155 ± 2 Ma (U–Pb, zircon) and 152 ± 5 Ma (K–Ar, hornblende), respectively, and provide a reliable minimum age (Kimmeridgian) for penetrative deformation in the Cache Creek terrane. K–Ar whole-rock dates from Cache Creek terrane and Ashcroft Formation argillites range from Early Permian (266 ± 8 Ma) and Early Jurassic (194 ± 6 Ma) to Late Jurassic, Kimmeridgian (154 ± 5 Ma). We interpret the younger dates as recording Middle–Late Jurassic tectonism and the older ones as possible relics from earlier deformation episodes.An Early Cretaceous K–Ar date (129 ± 5 Ma) for a lamprophyre dike that cuts the Nicola Group suggests that the Early Cretaceous magmatic arc of the Coast Plutonic Complex had an eastern alkalic fringe in the Intermontane Belt.

Download Full-text

A basal thunnosaurian from Iraq reveals disparate phylogenetic origins for Cretaceous ichthyosaurs

10.31233/osf.io/wnam4 ◽

2018 ◽

Author(s):

Valentin Fischer ◽

Darren Naish ◽

Jeff Liston ◽

Robert M Appleby ◽

James B Riding ◽

...

Keyword(s):

Middle East ◽

Early Cretaceous ◽

Late Jurassic ◽

Evolutionary History ◽

Early Jurassic ◽

Late Triassic ◽

Low Diversity ◽

History Of

Cretaceous ichthyosaurs have typically been considered a small, homo- geneous assemblage sharing a common Late Jurassic ancestor. Their low diversity and disparity have been interpreted as indicative of a decline lead- ing to their Cenomanian extinction. We describe the first post-Triassic ichthyosaur from the Middle East, Malawania anachronus gen. et sp. nov. from the Early Cretaceous of Iraq, and re-evaluate the evolutionary history of parvipelvian ichthyosaurs via phylogenetic and cladogenesis rate ana- lyses. Malawania represents a basal grade in thunnosaurian evolution that arose during a major Late Triassic radiation event and was previously thought to have gone extinct during the Early Jurassic. Its pectoral mor- phology appears surprisingly archaic, retaining a forefin architecture similar to that of its Early Jurassic relatives. After the initial latest Triassic radiation of early thunnosaurians, two subsequent large radiations pro- duced lineages with Cretaceous representatives, but the radiation events themselves are pre-Cretaceous. Cretaceous ichthyosaurs therefore include distantly related lineages, with contrasting evolutionary histories, and appear more diverse and disparate than previously supposed.

Download Full-text

AGE MODEL FOR LATE JURASSIC THROUGH EARLY CRETACEOUS USED IN THE GEOLOGIC TIMESCALE 2012/2016 REFERENCE SCALES

10.1130/abs/2018am-322883 ◽

2018 ◽

Author(s):

James G. Ogg ◽

◽

Chunju Huang ◽

Linda A. Hinnov ◽

...

Keyword(s):

Early Cretaceous ◽

Late Jurassic ◽

Age Model

Download Full-text

Theropod teeth from the basalmost Cretaceous of Anoual (Morocco) and their palaeobiogeographical significance

Geological Magazine ◽

10.1017/s0016756809005950 ◽

2009 ◽

Vol 146 (4) ◽

pp. 602-616 ◽

Cited By ~ 10

Author(s):

F. KNOLL ◽

J. I. RUIZ-OMEÑACA

Keyword(s):

Early Cretaceous ◽

Late Jurassic ◽

Dispersal Events ◽

Early Occurrence

AbstractThe theropod teeth from the Berriasian (Early Cretaceous) site of Anoual (N Morocco) are described. The assemblage is important in that it comes from one of the very few dinosaur sites of this age globally and the only one for the whole of Gondwana. The theropod teeth from Anoual are morphologically diverse. Most of the material possibly belongs to the clade Dromaeosauridae, which would be an early occurrence for this taxon. The palaeogeographic position of Anoual enables it to provide data on the dispersal events that affected terrestrial faunas during Mesozoic times. A Laurasian influence is evidenced by the presence of Velociraptorinae and, on the whole, the theropod fauna from Anoual provides support for the existence of a trans-Tethyan passage allowing terrestrial faunal interchanges during Late Jurassic and/or earliest Cretaceous times. Additionally, Anoual records the existence of diminutive theropods. However, it cannot yet be determined whether the small size of the specimens is genetic or ontogenetic.

Download Full-text