Temat: Maastrichtian - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Theropod teeth from the upper Maastrichtian Hell Creek Formation “Sue” Quarry: New morphotypes and faunal comparisons
Autorzy:: Gates, T.A.
Zanno, L.E.
Makovicky, P.J.
Powiązania:: https://bibliotekanauki.pl/articles/945614.pdf
Data publikacji:: 2015
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: paleontology
theropod
tooth
Upper Maastrichtian
Maastrichtian
Hell Creek Formation
morphotype
Dinosauria
morphometry
paleoecology
Cretaceous
North America
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2015, 60, 1; 131-139
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 2.

Tytuł:: Terminal Maastrichtian ammonites from Turkmenistan, Central Asia
Autorzy:: Machalski, M.
Jagt, J.W.M.
Alekseev, A.S.
Jagt-Yazykova, E.A.
Powiązania:: https://bibliotekanauki.pl/articles/20971.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: paleontology
Maastrichtian
ammonite
Turkmenistan
Central Asia
Ammonoidea
extinction
paleobiogeography
Cretaceous
Paleogene
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2012, 57, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 3.

Tytuł:: The last Cretaceous ammonites in Latin America
Autorzy:: Stinnesbeck, W.
Ifrim, C.
Salazar, C.
Powiązania:: https://bibliotekanauki.pl/articles/20513.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: paleontology
Cretaceous
ammonite
Latin America
Ammonoidea
Paleogene
Maastrichtian
Chile
Argentina
South America
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2012, 57, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 4.

Tytuł:: The lambeosaurine dinosaur Amurosaurus riabinini, from the Maastrichtian of Far Eastern Russia
Autorzy:: Godefroit, P
Bolotsky, Y.L.
Van Itterbeeck, J.
Powiązania:: https://bibliotekanauki.pl/articles/21185.pdf
Data publikacji:: 2004
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: phylogenesis
Late Cretaceous
Dinosauria
Russia
dinosaur
Amurosaurus riabinini
paleogeography
Maastrichtian
paleontology
Lambeosaurinae
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2004, 49, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 5.

Tytuł:: New frogs from the latest Cretaceous of Hateg Basin, Romania
Autorzy:: Venczel, M
Csiki, Z.
Powiązania:: https://bibliotekanauki.pl/articles/22784.pdf
Data publikacji:: 2003
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: terrestrial microvertebrate
aquatic microvertebrate
Romania
Cretaceous
fluvio-lacustrine deposit
anuran
Amphibia
frog
Anura
Hateg Basin
Maastrichtian
paleontology
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2003, 48, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 6.

Tytuł:: Theropod tooth assemblages from the Late Cretaceous Maevarano Formation and the possible presence of dromaeosaurids in Madagascar
Autorzy:: Fanti, F
Therrien, F.
Powiązania:: https://bibliotekanauki.pl/articles/20343.pdf
Data publikacji:: 2007
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: theropod diversity
Cretaceous
Late Cretaceous
dromaeosaurid
tooth
Maastrichtian
theropod tooth
paleobiogeography
Abelisauridae
Dinosauria
Madagascar
Campanian
paleontology
Dromaeosauridae
Maevarano Formation
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2007, 52, 1
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 7.

Tytuł:: First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters
Autorzy:: Claeson, K.M.
O'Leary, M.A.
Roberts, E.M.
Sissoko, F.
Bouare, M.
Tapanila, L.
Goodwin, D.
Gottfried, M.D.
Powiązania:: https://bibliotekanauki.pl/articles/20545.pdf
Data publikacji:: 2010
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: paleontology
first record
Mesozoic
stingray
Myliobatis wurnoensis
Mali
phylogenetic analysis
Myliobatidae
dentition
Chondrichthyes
Myliobatiformes
batoid fish
fish
Cretaceous
Maastrichtian
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2010, 55, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 8.

Tytuł:: Fusiteuthis polonica, a rare and unusual belemnite from the Maastrichtian
Autorzy:: Christensen, W K
Powiązania:: https://bibliotekanauki.pl/articles/21101.pdf
Data publikacji:: 2002
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: belemnitellid
belemnite
Polska
Fusiteuthis polonica
Belemnitellidae
Germany
Crimea
new genus
Maastrichtian
taxonomy
new species
paleontology
Belemnella lanceolata
Fusiteuthis
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2002, 47, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 9.

Tytuł:: Teeth of multituberculate mammals from the Late Cretaceous of Romania
Autorzy:: Csiki, Z
Grigorescu, D
Powiązania:: https://bibliotekanauki.pl/articles/22922.pdf
Data publikacji:: 2000
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: Hainina
Maastrichtian Sinpetru Formation
mammal
Romania
Late Cretaceous
Densus-Ciula Formation
tooth
Hateg Basin
Europe
paleontology
multituberculate mammal
Źródło:: Acta Palaeontologica Polonica; 2000, 45, 1
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 10.

Tytuł:: A symbiotic association of a boring polychaete and an echinoid from the Late Cretaceous of Germany
Autorzy:: Wisshak, M.
Neumann, C.
Powiązania:: https://bibliotekanauki.pl/articles/21643.pdf
Data publikacji:: 2006
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: paleontology
Germany
Cretaceous
Late Cretaceous
trace fossil
fossil
polychaete
Polychaeta
Spionidae
bioerosion
Maastrichtian
symbiotic association
echinoid
Caulostrepsis
Polydora
Echinocorys
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2006, 51, 3
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 11.

Tytuł:: A new Maastrichtian species of the centrosaurine ceratopsid Pachyrhinosaurus from the North Slope of Alaska
Autorzy:: Fiorillo, A.R.
Tykoski, R.S.
Powiązania:: https://bibliotekanauki.pl/articles/23291.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: Maastrichtian species
new species
centrosaurine ceratopsid
ceratopsid
Pachyrhinosaurus
Alaska
dinosaur
Pachyrhinosaurus perotorum
Dinosauria
Centrosaurinae
Cretaceous
Prince Creek Formation
Arctic
paleontology
remains
Opis:: The Cretaceous rocks of the Prince Creek Formation contain the richest record of polar dinosaurs found anywhere in the world. Here we describe a new species of horned dinosaur, Pachyrhinosaurus perotorum that exhibits an apomorphic character in the frill, as well as a unique combination of other characters. Phylogenetic analysis of 16 taxa of ceratopsians failed to resolve relationships between P. perotorum and other Pachyrhinosaurusspecies (P. canadensis and P. lakustai). P. perotorum shares characters with each of the previously known species that are not present in the other, including very large nasal and supraorbital bosses that are nearly in contact and separated only by a narrow groove as in P. canadensis, and a rostral comb formed by the nasals and premaxillae as in P. lakustai. P. perotorum is the youngest centrosaurine known (70–69 Ma), and the locality that produced the taxon, the Kikak−Tegoseak Quarry, is close to the highest latitude for recovery of ceratopsid remains.
Źródło:: Acta Palaeontologica Polonica; 2012, 57, 3
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 12.

Tytuł:: The titanosaur sauropods from the late Campanian-early Maastrichtian Allen Formation of Salitral Moreno, Rio Negro, Argentina
Autorzy:: Garcia, R.A.
Salgado, L.
Powiązania:: https://bibliotekanauki.pl/articles/20087.pdf
Data publikacji:: 2013
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: titanosaur sauropod
sauropod
Dinosauria
Saurischia
Sauropodomorpha
Sauropoda
Titanosauria
Titanosaur
Late Campanian
Early Maastrichtian
Allen Formation
Salitral Moreno
Rio Negro
Argentina
paleontology
Opis:: The dinosaur record of the Salitral Moreno locality (Río Negro Province, Argentina) is characterized by a high diversity of herbivore taxa, among them hadrosaurs, ankylosaurs, and titanosaur sauropods, but carnivores are rare, consisting of only a few fragmentary bones of small forms. Titanosaurs are represented by Rocasaurus muniozi and Aeolosaurus sp., and at least four other taxa, represented by fragmentary material. The elements preserved include a cervical, dorsal and caudal vertebrae, chevron, humerii, ulnae, radii, metacarpal, femora, tibiae, metatarsal, ischia, pubis, and ilium. The Allen Formation is thought to be correlated with the Marília Formation in Brazil, and their faunas have certain elements in common such as aeolosaurines, but saltasaurines and hadrosaurs, are known exclusively from the Allen Formation. These absences, and particularly that of the saltasaurines, may be because those sauropods originated late in the Cretaceous, probably in southern South America (Northern Patagonia?), and they did not have time to disperse to northern South America.
Źródło:: Acta Palaeontologica Polonica; 2013, 58, 2
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 13.

Tytuł:: New mammalian remains from the Late Cretaceous La Colonia Formation, Patagonia, Argentina
Autorzy:: Rougier, G W
Forasiepi, A.M.
Hill, R.V.
Novacek, M.
Powiązania:: https://bibliotekanauki.pl/articles/21844.pdf
Data publikacji:: 2009
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: paleontology
mammalian remains
Late Cretaceous
La Colonia Formation
Patagonia
Argentina
mammal fauna
Los Alamitos
Coloniatherium cilinskii
Vincelestes
Mammalia
Mesungulatidae
Cretaceous
new remains
Campanian
Maastrichtian
Opis:: 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.
Źródło:: Acta Palaeontologica Polonica; 2009, 54, 2; 195-212
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 14.

Tytuł:: Osteology and relationships of Olorotitan arharensis, a hollow−crested hadrosaurid dinosaur from the latest Cretaceous of Far Eastern Russia
Autorzy:: Godefroit, P.
Bolotsky, Y.L.
Bolotsky, I.Y.
Powiązania:: https://bibliotekanauki.pl/articles/20406.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: paleontology
osteology
relationship
Olorotitan arharensis
dinosaur
hadrosaurid dinosaur
Cretaceous
Russia
Dinosauria
Ornithischia
Hadrosauridae
Lambeosaurinae
phylogenesis
Late Cretaceous
Maastrichtian Udurchukan Formation
Corythosaurus casuarius Hypacrosaurus stebingeri
Hypacrosaurus altispinus
Opis:: The holotype of Olorotitan arharensis from the Maastrichtian Udurchukan Formation in Kundur, Far Eastern Russia, is the most complete dinosaur discovered in Russia and one of the best preserved lambeosaurines outside western North America. This taxon is diagnosed by following autapomorphies: large helmet−like hollow crest higher than the rest of the skull and extending caudally well beyond the level of the occiput; very high postorbital process of jugal (ratio height of postorbital process/length of jugal = 1); rostral portion of the jugal shorter than in other lambeosaurines, with a perfectly straight rostral margin; very asymmetrical maxilla in lateral view, with ventral margin distinctly downturned; very elongated neck composed of 18 cervical vertebrae; tibia as high as the femur; shorter cnemial crest, about one fifth of tibia length. A phylogenetic analysis, based on 118 cranial, dental, and postcranial characters, indicates that Olorotitan is a member of the Corythosaurini clade, and is the sister taxon of Corythosaurus casuarius, Hypacrosaurus stebingeri, and Hypacrosaurus altispinus. The high diversity and mosaic distribution of Maastrichtian hadrosaurid faunas in the Amur−Heilongjiang region are the result of a complex palaeogeographical history and imply that many independent hadrosaurid lineages dispersed readily between western America and eastern Asia at the end of the Cretaceous.
Źródło:: Acta Palaeontologica Polonica; 2012, 57, 3
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki