scholarly journals A possible brachiosaurid (Dinosauria, Sauropoda) from the mid-Cretaceous of northeastern China

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11957
Author(s):  
Chun-Chi Liao ◽  
Andrew Moore ◽  
Changzhu Jin ◽  
Tzu-Ruei Yang ◽  
Masateru Shibata ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
North America ◽  
Early Cretaceous ◽  
Northeast China ◽  
Late Jurassic ◽  
Evolutionary History ◽  
Phylogenetic Analyses ◽  
Convincing Evidence ◽  
Northeastern China

Brachiosauridae is a lineage of titanosauriform sauropods that includes some of the most iconic non-avian dinosaurs. Undisputed brachiosaurid fossils are known from the Late Jurassic through the Early Cretaceous of North America, Africa, and Europe, but proposed occurrences outside this range have proven controversial. Despite occasional suggestions that brachiosaurids dispersed into Asia, to date no fossils have provided convincing evidence for a pan-Laurasian distribution for the clade, and the failure to discover brachiosaurid fossils in the well-sampled sauropod-bearing horizons of the Early Cretaceous of Asia has been taken to evidence their genuine absence from the continent. Here we report on an isolated sauropod maxilla from the middle Cretaceous (Albian–Cenomanian) Longjing Formation of the Yanji basin of northeast China. Although the specimen preserves limited morphological information, it exhibits axially twisted dentition, a shared derived trait otherwise known only in brachiosaurids. Referral of the specimen to the Brachiosauridae receives support from phylogenetic analysis under both equal and implied weights parsimony, providing the most convincing evidence to date that brachiosaurids dispersed into Asia at some point in their evolutionary history. Inclusion in our phylogenetic analyses of an isolated sauropod dentary from the same site, for which an association with the maxilla is possible but uncertain, does not substantively alter these results. We consider several paleobiogeographic scenarios that could account for the occurrence of a middle Cretaceous Asian brachiosaurid, including dispersal from either North America or Europe during the Early Cretaceous. The identification of a brachiosaurid in the Longshan fauna, and the paleobiogeographic histories that could account for its presence there, are hypotheses that can be tested with continued study and excavation of fossils from the Longjing Formation.

scholarly journals A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7247 ◽  
Author(s):  
Scott Hartman ◽  
Mickey Mortimer ◽  
William R. Wahl ◽  
Dean R. Lomax ◽  
Jessica Lippincott ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
North America ◽  
Early Cretaceous ◽  
Late Jurassic ◽  
New Taxon ◽  
Morrison Formation ◽  
Postcranial Skeleton ◽  
Avian Flight ◽  
Multiple Alternative ◽  
Limb Proportions

The last two decades have seen a remarkable increase in the known diversity of basal avialans and their paravian relatives. The lack of resolution in the relationships of these groups combined with attributing the behavior of specialized taxa to the base of Paraves has clouded interpretations of the origin of avialan flight. Here, we describeHesperornithoides miesslerigen. et sp. nov., a new paravian theropod from the Morrison Formation (Late Jurassic) of Wyoming, USA, represented by a single adult or subadult specimen comprising a partial, well-preserved skull and postcranial skeleton. Limb proportions firmly establishHesperornithoidesas occupying a terrestrial, non-volant lifestyle. Our phylogenetic analysis emphasizes extensive taxonomic sampling and robust character construction, recovering the new taxon most parsimoniously as a troodontid close toDaliansaurus,Xixiasaurus, andSinusonasus. Multiple alternative paravian topologies have similar degrees of support, but proposals of basal paravian archaeopterygids, avialan microraptorians, andRahonavisbeing closer to Pygostylia than archaeopterygids or unenlagiines are strongly rejected. All parsimonious results support the hypothesis that each early paravian clade was plesiomorphically flightless, raising the possibility that avian flight originated as late as the Late Jurassic or Early Cretaceous.

scholarly journals New articulated asteroids (Echinodermata, Asteroidea) and ophiuroids (Echinodermata, Ophiuroidea) from the Late Jurassic (Volgian / Tithonian) of central Spitsbergen

2018 ◽  
Author(s):  
Julie Rousseau ◽  
Andrew Scott Gale ◽  
Ben Thuy
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Early Cretaceous ◽  
Outer Surface ◽  
Fossil Record ◽  
Late Jurassic ◽  
Evolutionary History ◽  
Two New Species ◽  
Latitudinal Position ◽  
Small Disc

The Late Jurassic–Early Cretaceous Slottsmøya Member of the Agardhfjellet Formation in central Spitsbergen has yielded two new species of asteroids and two species of ophiuroids, one of which is described as new. Polarasterias janusensis Rousseau & Gale gen. et sp. nov. is a forcipulatid neoasteroid with elongated arms, small disc and very broad ambulacral grooves with narrow adambulacrals. Savignaster septemtrionalis Rousseau & Gale sp. nov. is a pterasterid with well-developed interradial chevrons. The Spitsbergen specimens are the first described articulated material of Savignaster and reveal the overall arrangement of the ambulacral groove ossicles. Ophiogaleus sp. is an ophiacanthid with relatively long jaws and lateral arm plates, with a coarsely reticulate outer surface. Here again, we report the first articulated skeletons of this genus, providing unprecedented insights into the disc morphology. Ophioculina hoybergia Rousseau & Thuy gen. et sp. nov. is an ophiopyrgid with a well-developed arm comb and tentacle pores reduced to within-plate perforations starting at median arm segments. These new finds are important additions to the asterozoan fossil record with regard to their good degree of articulation and the high latitudinal position of the localities. They significantly add to the set of exhaustively known fossil asterozoan taxa which play a key role in the phylogenetic analysis and reconstruction of evolutionary history.

New multituberculate mammal from the Early Cretaceous of eastern North America

2013 ◽  
Vol 50 (3) ◽  
pp. 315-323 ◽  
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.

scholarly journals <i>Praecypridea</i>: a new non-marine ostracod genus from the Jurassic and Early Cretaceous of Europe, North and South America, and Africa

2010 ◽  
Vol 29 (2) ◽  
pp. 163-176 ◽  
Author(s):  
Benjamin Sames ◽  
Robin Whatley ◽  
Michael E. Schudack
Keyword(s):  
North America ◽  
South America ◽  
Early Cretaceous ◽  
Type Species ◽  
Late Jurassic ◽  
New Genus ◽  
Marine Habitats ◽  
Extinct Genus ◽  
North And South America ◽  
North And South

Abstract. The genus Praecypridea gen. nov. (Cypridoidea, Family Cyprideidae Martin, 1940) is described and thus far comprises four species: the type species Praecypridea acuticyatha (Schudack, 1998) comb. nov., Praecypridea postelongata (Oertli, 1957) comb. nov., Praecypridea suprajurassica (Mojon, Haddoumi &amp; Charriére, 2009) comb. nov. and Praecypridea acuta (Moos, 1959 in Wicher, 1959) comb. nov. Representatives of the new genus have been described from the Middle to Late Jurassic of Europe, North America and Africa and the Early Cretaceous of South America, with other presumed representatives also occurring in the Early Cretaceous. Species of Praecypridea are considered to represent members of the ancestral lineage of the extinct genus Cypridea Bosquet, representatives of which flourished in non-marine habitats of latest Jurassic to Early Cretaceous age and account for the first period of abundance of the non-marine Cypridoidea.

scholarly journals Extreme diversity and parasitism of Late Jurassic squat lobsters (Decapoda: Galatheoidea) and the oldest records of porcellanids and galatheids

2019 ◽  
Vol 187 (4) ◽  
pp. 1131-1154 ◽  
Author(s):  
Cristina M Robins ◽  
Adiël A Klompmaker
Keyword(s):  
Early Cretaceous ◽  
Late Jurassic ◽  
Evolutionary History ◽  
Common Species ◽  
Statistical Analyses ◽  
Decapod Crustaceans ◽  
Squat Lobsters

AbstractGalatheoid decapod crustaceans consist of ~1250 species today, but their evolutionary history and origin are poorly known. We studied the largest known fossil galatheoid assemblage, from the Late Jurassic of Ernstbrunn, Austria. This coral-associated assemblage yielded 2348 specimens, arranged in 53 species, 22 genera and six families. Rarefaction analyses show that nearly all taxa have been collected. In addition to abundant Munidopsidae, this assemblage also contains the oldest members of four of the six galatheoid families, including Galatheidae, Munididae, Paragalatheidae and Porcellanidae. We describe the oldest Porcellanidae and Galatheidae to date, and a catillogalatheid: Vibrissalana jurassica gen. et sp. nov., ?Galathea genesis sp. nov. and Galatheites britmelanarum sp. nov. Our re-examination of the oldest claimed porcellanid, Jurellana tithonia, from Ernstbrunn, indicates that it represents a homolodromioid brachyuran, ascribed to Jurellanidae fam. nov. along with Ovalopus gen. nov. The second-oldest claimed porcellanid, Early Cretaceous Petrolisthes albianicus, is transferred to the catillogalatheid Hispanigalathea. We further document that 10.4% of Ernstbrunn galatheoid specimens were parasitized by epicaridean isopods, as shown by swellings in the gill region. Statistical analyses indicate that infestation is near non-random, varying from 0 to 33% for common species. Thus, Late Jurassic coral-associated habitats were key ecosystems in the evolution of galatheoids and their parasites.

scholarly journals A new ornithurine from the Early Cretaceous of China sheds light on the evolution of early ecological and cranial diversity in birds

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1765 ◽  
Author(s):  
Jiandong Huang ◽  
Xia Wang ◽  
Yuanchao Hu ◽  
Jia Liu ◽  
Jennifer A. Peteya ◽  
...  
Keyword(s):  
New Species ◽  
Early Cretaceous ◽  
Late Cretaceous ◽  
Late Jurassic ◽  
Northeastern China ◽  
Avian Ecology ◽  
Developmental Shift ◽  
Cranial Ontogeny ◽  
Close Relatives

Despite the increasing number of exceptional feathered fossils discovered in the Late Jurassic and Cretaceous of northeastern China, representatives of Ornithurae, a clade that includes comparatively-close relatives of crown clade Aves (extant birds) and that clade, are still comparatively rare. Here, we report a new ornithurine speciesChangzuiornis ahgmifrom the Early Cretaceous Jiufotang Formation. The new species shows an extremely elongate rostrum so far unknown in basal ornithurines and changes our understanding of the evolution of aspects of extant avian ecology and cranial evolution. Most of this elongate rostrum inChangzuiornis ahgmiis made up of maxilla, a characteristic not present in the avian crown clade in which most of the rostrum and nearly the entire facial margin is made up by premaxilla. The only other avialans known to exhibit an elongate rostrum with the facial margin comprised primarily of maxilla are derived ornithurines previously placed phylogenetically as among the closest outgroups to the avian crown clade as well as one derived enantiornithine clade. We find that, consistent with a proposed developmental shift in cranial ontogeny late in avialan evolution, that this elongate rostrum is achieved through elongation of the maxilla while the premaxilla remains only a small part of rostral length. Thus, only in Late Cretaceous ornithurine taxa does the premaxilla begin to play a larger role. The rostral and postcranial proportions ofChangzuiornissuggest an ecology not previously reported in Ornithurae; the only other species with an elongate rostrum are two marine Late Cretacous taxa interpreted as showing a derived picivorous diet.

scholarly journals Phylogeny and morphologic evolution of the Ordovician Camerata (Class Crinoidea, Phylum Echinodermata)

2017 ◽  
Vol 91 (4) ◽  
pp. 815-828 ◽  
Author(s):  
Selina R. Cole
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Evolutionary History ◽  
Phylogenetic Analyses ◽  
Major Group ◽  
Higher Taxa ◽  
Morphologic Evolution ◽  
Phylogenetic Framework ◽  
Selection For

AbstractThe subclass Camerata (Crinoidea, Echinodermata) is a major group of Paleozoic crinoids that represents an early divergence in the evolutionary history and morphologic diversification of class Crinoidea, yet phylogenetic relationships among early camerates remain unresolved. This study conducted a series of quantitative phylogenetic analyses using parsimony methods to infer relationships of all well-preserved Ordovician camerate genera (52 taxa), establish the branching sequence of early camerates, and test the monophyly of traditionally recognized higher taxa, including orders Monobathrida and Diplobathrida. The first phylogenetic analysis identified a suitable outroup for rooting the Ordovician camerate tree and assessed affinities of the atypical dicyclic family Reteocrinidae. The second analysis inferred the phylogeny of all well-preserved Ordovician camerate genera. Inferred phylogenies confirm: (1) the Tremadocian genera Cnemecrinus and Eknomocrinus are sister to the Camerata; (2) as historically defined, orders Monobathrida and Diplobathrida do not represent monophyletic groups; (3) with minimal revision, Monobathrida and Diplobathrida can be re-diagnosed to represent monophyletic clades; (4) family Reteocrinidae is more closely related to camerates than to other crinoid groups currently recognized at the subclass level; and (5) several genera in subclass Camerata represent stem taxa that cannot be classified as either true monobathrids or true diplobathrids. The clade containing Monobathrida and Diplobathrida, as recognized herein, is termed Eucamerata to distinguish its constituent taxa from more basally positioned taxa, termed stem eucamerates. The results of this study provide a phylogenetic framework for revising camerate classification, elucidating patterns of morphologic evolution, and informing outgroup selection for future phylogenetic analyses of post-Ordovician camerates.

Dates and rates in ancient lakes: 40Ar–39Ar evidence for an Early Cretaceous age for the Jehol Group, northeast China

1995 ◽  
Vol 32 (9) ◽  
pp. 1426-1431 ◽  
Author(s):  
Patrick E. Smith ◽  
Norman M. Evensen ◽  
Derek York ◽  
Mee-Mann Chang ◽  
Fan Jin ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Northeast China ◽  
Late Jurassic ◽  
Lacustrine Sediments ◽  
Yixian Formation ◽  
Liaoning Province ◽  
Absolute Calibration ◽  
Small Fault ◽  
Absolute Age ◽  
Good Agreement

The correlation of freshwater sediments in small, fault-bound basins in Liaoning Province, northeast China, known as the Jehol (or Rehe) Group, has been a subject of debate for many years, with biochronological estimates ranging from Late Jurassic to the Cretaceous periods. We have applied the laser 40Ar–39Ar technique to volcanic intercalations and lacustrine sediments from the Yixian Formation at the base of the Jehol Group. Minerals and whole-rock chips from the upper parts of the Yixian Formation give concordant ages with a mean of 121.1 ± 0.2 Ma (1σ). Ages for samples near the base of the Yixian Formation give 121.4 ± 0.6 and 122.9 ± 0.3 Ma, and appear to be synchronous or only slightly older than the top of the formation. Integrated ages of 122 Ma for glaucony from the lacustrine sediments lying stratigraphically between the upper and lower parts of the Yixian are in very good agreement with the absolute age framework provided by the volcanic units. Such disseminated facies of this clay show promise for directly dating lacustrine sediments. All of the above 40Ar–39Ar dates provide an absolute calibration of the Yixian Formation, and show that the whole formation was deposited entirely within Early Cretaceous time over an interval of no more than 2–3 Ma.

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.

A new basal hadrosauriform dinosaur (Ornithischia: Iguanodontia) from the Early Cretaceous of northwestern China

2009 ◽  
Vol 46 (12) ◽  
pp. 949-957 ◽  
Author(s):  
Hai-Lu You ◽  
Da-Qing Li
Keyword(s):  
Phylogenetic Analysis ◽  
North America ◽  
Early Cretaceous ◽  
Gansu Province ◽  
Northwestern China ◽  
Occipital Condyle ◽  
Close Relative ◽  
Asian Origin ◽  
Posterior Portion ◽  
Early Late

A new hadrosauriform dinosaur, Jintasaurus meniscus gen. et sp. nov., is reported from the Lower Cretaceous Xinminpu Group of the Yujingzi Basin, Jiuquan area, Gansu Province, northwestern China. It is represented by an articulated posterior portion of the skull and is unique in having an extremely long, pendant and crescentic paroccipital process with its ventral tip projecting far beyond the ventral level of the occipital condyle. Phylogenetic analysis recovers Jintasaurus as the sister-taxon to Hadrosauroidea, more derived than other Early Cretaceous hadrosauriforms and Protohadros from the early Late Cretaceous of North America. This discovery adds one more close relative to Hadrosauroidea in Asia and supports an Asian origin for this group.

Sign in / Sign up

Export Citation Format

Share Document