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Comment on “A new Arctic hadrosaurid from the Prince Creek Formation (lower Maastrichtian) of northern Alaska” by Hirotsugu Mori, Patrick S. Druckenmiller, and Gregory M. Erickson

100%

Fiorillo A. R.

Acta Palaeontologica Polonica

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2016

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tom 61

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nr 1

2

Terminal Maastrichtian ammonites from Turkmenistan, Central Asia

84%

Machalski M., Jagt J. W. M., Alekseev A. S., Jagt-Yazykova E. A.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

A complete uppermost Maastrichtian–Danian succession in the Sumbar River section, western Kopet Dagh (southwest Turkmenistan, Central Asia), constitutes one of the few instances in the world where the fossil record of the last ammonites can be directly positioned with respect to the iridium−rich, impact−related clay layer, which defines the Cretaceous–Paleogene (K–Pg) boundary. Two ammonite taxa, Baculites cf. vertebralis and Hoploscaphites constrictus johnjagti, range up to a level directly beneath the K–Pg boundary clay in the Sumbar River section. Thus, these two forms probably survived until the very end of the Maastrichtian in the western Kopet Dagh area. The terminal Maastrichtian ammonite records from the Sumbar River area represent the southeasternmost occurrences of these essentially Boreal taxa.

3

The last Cretaceous ammonites in Latin America

84%

Stinnesbeck W., Ifrim C., Salazar C.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

Sections yielding late Maastrichtian ammonite assemblages are rare in Latin America and precise biostratigraphic correlation with European type sections remains difficult. In all, the extinction pattern of ammonites appears to differ between sites in southern high latitudes and those in the tropics to subtropics. In austral sections of Chile, and possibly also in southern Argentina, diverse assemblages range throughout most of the substage and then show a gradual decline prior to the Cretaceous–Paleogene (K–Pg) boundary. Further north, in northeast Brazil, only two genera (Diplomoceras, Pachydiscus) range into the uppermost Maastrichtian, but disappear within the last 0.3 Ma of the Cretaceous. In tropical sections of Columbia and Mexico, the decline of ammonites started earlier and Sphenodiscus is the last ammonite known to occur in the late Maastrichtian. In all sections revised here the disappearance of ammonites was completed prior to the end of the Maastrichtian and was thus independent of the asteroid impact at, or near, the end of the Cretaceous.

4

New lissamphibians and squamates from the Maastrichtian of Hateg Basin, Romania

84%

Folie A., Codrea V.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 1

Numerous remains of amphibians and squamates were discovered in the continental sediments of the Maastrichtian Sânpetru Formation, south of Pui Village (Haţeg Basin, western Romania). The lissamphibians are represented by a salamander−like allocaudatan (Albanerpeton sp.) and at least two discoglossid frogs (cf. Eodiscoglossussp. and cf. Paradiscoglossussp.). The numerous lizards are represented by, e.g., the teiid Bicuspidon hatzegiensissp. nov., and for the first time in a Late Cretaceous site, by two species of the paramacellodid Becklesius (Becklesius nopcsai sp. nov. and Becklesius cf. B. hoffstetteri). Snakes are also present in this site by an indeterminante madtsoiid, which represents the first occurrence of this family in eastern Europe. The presence of Albanerpeton in this site confirms that this genus appeared in Europe by at least the Late Cretaceous instead of Miocene as previously thought. The presence of both Albanerpeton and Bicuspidon in Haţeg Basin suggests a North American influence on eastern European amphibian and lacertilian faunas by Maastrichtian times.

5

The lambeosaurine dinosaur Amurosaurus riabinini, from the Maastrichtian of Far Eastern Russia

84%

Godefroit P., Bolotsky Y. L., Van Itterbeeck J.

Acta Palaeontologica Polonica

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2004

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tom 49

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nr 4

Amurosaurus riabinini Bolotsky and Kurzanov, 1991 (Dinosauria, Hadrosauridae) is described on the basis of numerous disarticulated bones from the Maastrichtian Udurchukan Formation of Blagoveschensk, Far Eastern Russia. Comparisons with North American palynozones and their well−calibrated ages suggest that this formation is late Maastrichtian in age. It is shown that A. riabinini is a valid species, characterised by cranial and postcranial autapomorphies. A phylogenetic analysis, based on 40 cranial, dental, and postcranial characters, indicates that this taxon occupies a relatively basal position within the lambeosaurine subfamily as the sister−taxon of a monophyletic group formed by the parasauroloph and corythosaur clades. This cladogram also demonstrates that lambeosaurines have an Asian origin. In eastern Asia, lambeosaurine dinosaurs dominate late Maastrichtian dinosaur localities, whereas this group is apparently no longer represented in synchronous localities from western North America.

6

Theropod teeth from the upper Maastrichtian Hell Creek Formation “Sue” Quarry: New morphotypes and faunal comparisons

67%

Gates T. A., Zanno L. E., Makovicky P. J.

Acta Palaeontologica Polonica

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2015

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tom 60

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nr 1

Isolated teeth from vertebrate microfossil localities often provide unique information on the biodiversity of ancient ecosystems that might otherwise remain unrecognized. Microfossil sampling is a particularly valuable tool for documenting taxa that are poorly represented in macrofossil surveys due to small body size, fragile skeletal structure, or relatively low ecosystem abundance. Because biodiversity patterns in the late Maastrichtian of North American are the primary data for a broad array of studies regarding non-avian dinosaur extinction in the terminal Cretaceous, intensive sampling on multiple scales is critical to understanding the nature of this event. We address theropod biodiversity in the Maastrichtian by examining teeth collected from the Hell Creek Formation locality that yielded FMNH PR 2081 (the Tyrannosaurus rex specimen “Sue”). Eight morphotypes (three previously undocumented) are identified in the sample, representing Tyrannosauridae, Dromaeosauridae, Troodontidae, and Avialae. Noticeably absent are teeth attributed to the morphotypes Richardoestesia and Paronychodon. Morphometric comparison to dromaeosaurid teeth from multiple Hell Creek and Lance formations microsites reveals two unique dromaeosaurid morphotypes bearing finer distal denticles than present on teeth of similar size, and also differences in crown shape in at least one of these. These findings suggest more dromaeosaurid taxa, and a higher Maastrichtian biodiversity, than previously appreciated.

7

A symbiotic association of a boring polychaete and an echinoid from the Late Cretaceous of Germany

67%

Wisshak M., Neumann C.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 3

From the Early Maastrichtian white chalk of Rügen Island (N Germany), a specimen of the echinoid Echinocorys ovata featuring 27 boring traces of the ichnogenus Caulostrepsis is described. Individual traces are shallow to moderately deep U−shaped depressions and show distinct regeneration textures evidencing a syn−vivo infestation. All traces are located on the plastron between the peristome and periproct of the host echinoid, indicating an adaptation of the trace maker by choosing the most advantageous position of the specific host. The traces are attributed to the work of boring spionid polychaetes (Polydora complex), grounded on the close morphological resemblance with initial borings of Recent polydorids. This is the first evidence for a possible association of a boring polychaete not only with an echinoid but with an echinoderm in general. The symbiotic relationship was commensalistic in nature with the spionid probably taking advantage of organic matter resuspended by the echinoids locomotion and feeding activity and benefiting from effective shelter. For the host echinoid, the association was moderately harmful. The soft bottom environment of the chalk sea provided very limited hard substrate ecospace for settlers and bioeroders, available only in form of biogenic structures. Echinocorys was a dominant component of this benthic community and can be considered as a suitable host for symbiotic interactions because of its size and assumed longevity.

8

New elmisaurine specimens from North America and their relationship to the Mongolian Elmisaurus rarus

67%

Funston G. F., Currie P. J., Burns M. E.

Acta Palaeontologica Polonica

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2016

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tom 61

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nr 1

New specimens from Canada confirm the presence of elmisaurines in North America and shed light on the relationship of Leptorhynchos elegans to Mongolian forms. These specimens have hindlimb elements previously unknown from elmisaurines in the Dinosaur Park Formation, including tibiae and pedal phalanges. Metatarsal anatomy is sufficiently different to merit a generic distinction from Elmisaurus rarus, and both can be distinguished from Caenagnathus collinsi and Chirostenotes pergracilis. Differences between these taxa include body size, degree of coossification of the tarsometatarsus, and development of cruciate ridges of the metatarsal III. Histological analysis confirms that these differences are not correlated with ontogenetic age of the specimens. The results support the informal separation of caenagnathids based on metatarsal structure, and allow comments on paleobiological differences between caenagnathids and oviraptorids.

9

Latest Cretaceous leaf floras from southern Poland and western Ukraine

67%

Halamski A. T.

Acta Palaeontologica Polonica

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2013

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tom 58

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nr 2

Latest Cretaceous (Campanian to Maastrichtian) leaf fossil assemblages are described from 33 exposures ranging from the southern border of the Holy Cross Mountains (southern Poland) through the Roztocze region (south−eastern Poland) to the vicinity of L’viv (western Ukraine). The fossil assemblage is allochthonous, preserved in marine sediments, yet complete compound leaves strongly argue for the transport having been short. Krasnobród and Potelych (Potylicz) are the richest localities; both are late Campanian. The abundance of angiosperm remains in this period is explained by a marine lowstand resulting in nearby emergent vegetated areas. The flora was composed of ferns (three species), conifers (five species, including the commonest Geinitzia reichenbachii), dicotyledons (seventeen taxa; Debeya paulinae sp. nov., two other species of Debeya, and Rarytkinia polonica being the most frequent), and a single presumed monocotyledon. The eudicot clade is formalised as supersubclass Eudicotyledoneae Doyle and Hotton ex Halamski, herein. The approximately equal abundance of serrate/lobate and entire−margined dicots attests to an intermediate character of the flora between more thermophilic and polar vegetation. The material may have come from at least two communities: xeromorphic mixed Debeya−conifer forests and platanoid−Lauraceae forests growing in disturbed environments along rivers. The assemblage is most similar to approximately coeval floras from Westphalia and the Netherlands.

10

First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

67%

Claeson K. M., O'Leary M. A., Roberts E. M., Sissoko F., Bouare M., Tapanila L., Goodwin D., Gottfried M. D.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 4

New specimens, including the first record of lower dental plates, of the extinct myliobatid Myliobatis wurnoensis were recovered from the Maastrichtian (Late Cretaceous) of the Iullemmeden Basin, Mali, and are the oldest record of the taxon. We evaluated the phylogenetic position of this taxon with reference to other myliobatids (extinct and extant) using osteology and dentition. Our results indicate that Myliobatinae and Myliobatis are each paraphyletic, and that Aetobatus and Rhinoptera are monophyletic. We also found that taxa known only from the Cretaceous, Brachyrhizodus and Igdabatis, are highly nested within Myliobatidae. The phylogenetic position of these taxa unambiguously extends the origin of Myliobatidae and most of its representative taxa into the Mesozoic.

11

A new Arctic hadrosaurid from the Prince Creek Formation (lower Maastrichtian) of northern Alaska

67%

Mori H., Druckenmiller P. S., Erickson G. M.

Acta Palaeontologica Polonica

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2016

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tom 61

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nr 1

The Liscomb bonebed in the Price Creek Formation of northern Alaska has produced thousands of individual bones of a saurolophine hadrosaurid similar to Edmontosaurus; however, the specific identity of this taxon has been unclear, in part because the vast majority of the remains represent immature individuals. In this study, we address the taxonomic status of the Alaskan material through a comparative and quantitative morphological analysis of juvenile as well several near adult-sized specimens with particular reference to the two known species of Edmontosaurus, as well as a cladistic analysis using two different matrices for Hadrosauroidea. In the comparative morphological analysis, we introduce a quantitative method using bivariate plots to address ontogenetic variation. Our comparative anatomical analysis reveals that the Alaskan saurolophine possesses a unique suite of characters that distinguishes it from Edmontosaurus, including a premaxillary circumnarial ridge that projects posterolaterally without a premaxillary vestibular promontory, a shallow groove lateral to the posterodorsal premaxillary foramen, a relatively narrow jugal process of the postorbital lacking a postorbital pocket, a relatively tall maxilla, a relatively gracile jugal, a more strongly angled posterior margin of the anterior process of the jugal, wide lateral exposure of the quadratojugal, and a short symphyseal process of the dentary. The cladistic analyses consistently recover the Alaskan saurolophine as the sister taxon to Edmontosaurus annectens + Edmontosaurus regalis. This phylogenetic assessment is robust even when accounting for ontogenetically variable characters. Based on these results, we erect a new taxon, Ugrunaaluk kuukpikensis gen. et sp. nov. that contributes to growing evidence for a distinct, early Maastrichtian Arctic dinosaur community that existed at the northernmost extent of Laramidia during the Late Cretaceous.

12

A unique dentary suggests a third genus of batrachosauroidid salamander existed during the latest Cretaceous in the western USA

67%

Gardner J. D.

Acta Palaeontologica Polonica

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2022

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tom 67

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nr 1

13

New mammalian remains from the Late Cretaceous La Colonia Formation, Patagonia, Argentina

67%

Rougier G. W., Forasiepi A. M., Hill R. V., Novacek M.

Acta Palaeontologica Polonica

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2009

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tom 54

|

nr 2

195-212

Knowledge of the latest Late Cretaceous mammalian fauna in the South America was, until now, mostly based on dentally known taxa recovered at Los Alamitos (Río Negro, Argentina). Here we describe new mammalian remains collected in outcrops of the La Colonia Formation (Campanian–Maastrichtian) exposed in Chubut Province, Argentina, warranting the recognition of a new mesungulatid: Coloniatherium cilinskii gen. et sp. nov. The mammalian high−level taxonomic compositions of the localities in the La Colonia Formation and at Los Alamitos are roughly similar (Reigitheriidae, Mesungulatidae, and Ferugliotheridae are represented in both localities), but gondwanatheriids and the more plesiomorphic dryolestoids from Los Alamitos are missing from La Colonia. The most abundant mammalian remains collected at La Colonia correspond to large−sized mesungulatids. Coloniatherium cilinskii is recognized by the dentition and lower jaw, and we assign five isolated petrosal bones, focusing our study primarily on the analysis of the ear regions. The morphology of the petrosals suggests a phylogenetic position similar to Vincelestes, but sharing some derived features, possibly convergent, with therians. Attribution of the petrosals to the mesungulatid Coloniatherium cilinskii is supported by overall morphology, size, and relative abundance among the mammalian remains from La Colonia.

14

Latest Maastrichtian foraminiferal Abathomphalus mayaroensis zone in the Subsilesian unit [Polish Outer Carpathians]

67%

Gasinski M. A., Lesniak T., Piotrowski M.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2001

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tom 49

|

nr 2

15

Crustacean burrows from Upper Maastrichtian deposits of South-Central Cuba

67%

Pszczolkowski A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2002

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tom 50

|

nr 2

16

Theropod tooth assemblages from the Late Cretaceous Maevarano Formation and the possible presence of dromaeosaurids in Madagascar

67%

Fanti F., Therrien F.

Acta Palaeontologica Polonica

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2007

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tom 52

|

nr 1

The latest Cretaceous (Campanian?–Maastrichtian) Maevarano Formation of the Mahajanga Basin, Madagascar, preserves one of the most diverse fossil vertebrate faunas of the Gondwanan landmasses. Over 180 isolated theropod teeth recovered from that formation were studied in order to document theropod diversity in the Madagascar insular setting. Tooth morphology and characteristics of the Maevarano teeth were compared to those of known theropod teeth for identification, including the Malagasy non−avian theropods Majungatholus atopus and Masiakasaurus knopfleri. Tooth and denticle morphologies permit the recognition of five tooth morphotypes: three morphotypes are referable to Majungatholus atopus based on variation in tooth morphology observed in teeth preserved in situ in the jaws of two specimens, and one morphotype is ascribable to Masiakasaurus knopfleri. Teeth pertaining to the fifth morphotype differ from other morphotypes in the size and orientation of the denticles, shape and orientation of blood grooves, and in general tooth morphology. Statistical analyses reveal that the fifth Maevarano tooth morphotype is similar to dromaeosaurid teeth, suggesting that a yet unknown theropod taxon inhabited Madagascar during the latest Cretaceous. This morphotype represents the first evidence of the possible presence of a dromaeosaurid in Madagascar and supports the theory that dromaeosaurids were present throughout Pangaea before the break−up of the supercontinent during the Late Jurassic and had colonized Madagascar before its separation from Africa during the Early Cretaceous.

17

Biostratigraphy and palaeoenvironmental analysis of the Zegocina marls in the Zegocina tectonic window [Subsilesian Unit, Polish Outer Carpathians

67%

Gasinski M. A., Lesniak T., Wrobel A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2003

|

tom 51

|

nr 1

18

New frogs from the latest Cretaceous of Hateg Basin, Romania

67%

Venczel M., Csiki Z.

Acta Palaeontologica Polonica

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2003

|

tom 48

|

nr 4

The latest Cretaceous (Maastrichtian) fluvio−lacustrine deposits of Haţeg Basin (Romania) have yielded a number of aquatic and terrestrial microvertebrates, including dissociated skeletal remains of the following anuran taxa: Hatzegobatrachus grigorescui gen. et sp. nov., Paralatonia transylvanica gen. et sp. nov., andAnura indet. H. grigorescui sp. nov. (type species), retaining some leiopelmatid−grade anuran features, is diagnosed as a small−sized primitive frog with still unclear relationships. P. transylvanica sp. nov. (type species) is a middle−sized discoglossine frog. Based on the characters of jaw−bones andpost−cranial skeletal elements, it appears as intermediate between primitive (Eodiscoglossus−like) andmore derived (Latonia−like) discoglossine discoglossid. In Hatzegobatrachus and Paralatonia the morphology of the hipbones shows that they differ in saltatorial abilities. Consequently, these forms may have occupied distinct ecological niches, suggesting that the latest Cretaceous microvertebrate assemblages of Haţeg Basin were connectedto more complex ecosystems than considered before.

19

Fusiteuthis polonica, a rare and unusual belemnite from the Maastrichtian

67%

Christensen W. K.

Acta Palaeontologica Polonica

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2002

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tom 47

|

nr 4

A specimen of Fusiteuthis polonica, from the basal Maastrichtian of the “Saturn” chalk pit at Kronsmoor in northwest Germany, is described. It came from the uppermost part of the Belemnella lanceolata Zone, ca. 9.5 m above the base of the Maastrichtian as defined on belemnites. Fusiteuthis was very rare, but widely distributed. Single occurrences are known from northwest Germany, Poland and Crimea. It has been recorded only from the lowest and uppermost parts of the Maastrichtian; the longevity of this genus was thus slightly less than 6 myr. Fusiteuthis belongs to the Upper Cretaceous belemnite family Belemnitellidae.

20

New Late Cretaceous microvertebrate assemblage from the Campanian-Maastrichtian Williams Fork Formation, northwestern Colorado, USA, and its paleoenvironmental implications

51%

Brand N. A., Heckert A. B., Sanchez I., Foster J. R., Hunt_Foster R. K., Eberle J. J.

Acta Palaeontologica Polonica

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2022

|

tom 67

|

nr 3

Ograniczanie wyników

Comment on “A new Arctic hadrosaurid from the Prince Creek Formation (lower Maastrichtian) of northern Alaska” by Hirotsugu Mori, Patrick S. Druckenmiller, and Gregory M. Erickson

Terminal Maastrichtian ammonites from Turkmenistan, Central Asia

The last Cretaceous ammonites in Latin America

New lissamphibians and squamates from the Maastrichtian of Hateg Basin, Romania

The lambeosaurine dinosaur Amurosaurus riabinini, from the Maastrichtian of Far Eastern Russia

Theropod teeth from the upper Maastrichtian Hell Creek Formation “Sue” Quarry: New morphotypes and faunal comparisons

A symbiotic association of a boring polychaete and an echinoid from the Late Cretaceous of Germany

New elmisaurine specimens from North America and their relationship to the Mongolian Elmisaurus rarus

Latest Cretaceous leaf floras from southern Poland and western Ukraine

First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

A new Arctic hadrosaurid from the Prince Creek Formation (lower Maastrichtian) of northern Alaska

A unique dentary suggests a third genus of batrachosauroidid salamander existed during the latest Cretaceous in the western USA

New mammalian remains from the Late Cretaceous La Colonia Formation, Patagonia, Argentina

Latest Maastrichtian foraminiferal Abathomphalus mayaroensis zone in the Subsilesian unit [Polish Outer Carpathians]

Crustacean burrows from Upper Maastrichtian deposits of South-Central Cuba

Theropod tooth assemblages from the Late Cretaceous Maevarano Formation and the possible presence of dromaeosaurids in Madagascar

Biostratigraphy and palaeoenvironmental analysis of the Zegocina marls in the Zegocina tectonic window [Subsilesian Unit, Polish Outer Carpathians

New frogs from the latest Cretaceous of Hateg Basin, Romania

Fusiteuthis polonica, a rare and unusual belemnite from the Maastrichtian

New Late Cretaceous microvertebrate assemblage from the Campanian-Maastrichtian Williams Fork Formation, northwestern Colorado, USA, and its paleoenvironmental implications