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

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.

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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.

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

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.180.1.5 ◽

2009 ◽

Vol 180 (1) ◽

pp. 5-11 ◽

Cited By ~ 46

Author(s):

José Ignacio Canudo ◽

José Luis Barco ◽

Xabier Pereda-Suberbiola ◽

José Ignacio Ruiz-Omeñaca ◽

Leonardo Salgado ◽

...

Keyword(s):

Iberian Peninsula ◽

Northern Hemisphere ◽

Early Cretaceous ◽

Late Jurassic ◽

Open Ocean ◽

Early Jurassic ◽

Place Of Origin ◽

Iberian Margin ◽

Great Development ◽

Iberian Plate

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.

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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

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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.

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Late Jurassic-Early Cretaceous palynostratigraphy and palaeoclimate in the Andigama Basin, Sri Lanka

Journal of Asian Earth Sciences X ◽

10.1016/j.jaesx.2021.100067 ◽

2021 ◽

pp. 100067

Author(s):

Panchala Weerakoon ◽

Harinam Joshi ◽

Neha Aggarwal ◽

Neerja Jha ◽

Hetti Arachchige Hemachandra Jayasena ◽

...

Keyword(s):

Sri Lanka ◽

Early Cretaceous ◽

Late Jurassic

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Late Jurassic-Early Cretaceous inversion of the northern East Shetland Basin, northern North Sea

Geological Society London Special Publications ◽

10.1144/gsl.sp.1995.088.01.16 ◽

1995 ◽

Vol 88 (1) ◽

pp. 275-306 ◽

Cited By ~ 14

Author(s):

D. W. Thomas ◽

M. P. Coward

Keyword(s):

North Sea ◽

Early Cretaceous ◽

Late Jurassic ◽

Northern North Sea

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Ordosemys leios, n.gen., n.sp., a new turtle from the Early Cretaceous of the Ordos Basin, Inner Mongolia

Canadian Journal of Earth Sciences ◽

10.1139/e93-184 ◽

1993 ◽

Vol 30 (10) ◽

pp. 2128-2138 ◽

Cited By ~ 50

Author(s):

Donald B. Brinkman ◽

Jiang-Hua Peng

Keyword(s):

Early Cretaceous ◽

Inner Mongolia ◽

Cervical Vertebrae ◽

Ordos Basin ◽

Sister Group ◽

Sister Group Relationship ◽

Articular Surfaces ◽

Caudal Vertebrae ◽

The Ordos Basin

Ordosemys leios, n.gen., n.sp., from the Early Cretaceous Luohandong Formation, Zhidan Group, Ordos Basin, Inner Mongolia, is a primitive aquatic turtle with a reduced, fenestrated plastron. It shares with the members of the Centrocryptodira the presence of well-formed articular surfaces on the cervical and caudal vertebrae. Within the Centrocryptodira, characters of the cervical vertebrae suggest it is more closely related to the Polycryptodira than is the Meiolaniidae. Ordosemys shares with the Chelydridae the presence of two procoelous anterior caudals, but this character may be primitive for the Polycryptodira. Characters of the basicranial region of the braincase shared by Ordosemys and the Chelonioidea support a sister-group relationship between these two taxa, but a sister-group relationship between Ordosemys and the Polycryptodira is more strongly supported by characters shared by the Chelonioidea and other members of the Polycryptodira.

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