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Tytuł:
Anatomy and relationships of the Triassic temnospondyl Sclerothorax
Autorzy:
Schoch, R R
Fastnacht, M.
Fichter, J.
Keller, T.
Powiązania:
https://bibliotekanauki.pl/articles/20469.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
terrestrial vertebrate
Temnospondyli
Stereospondyli
Triassic
Buntsandstein
anatomy
Sclerothorax
Germany
Sclerothorax hypselonotus
paleontology
Opis:
Recently, new material of the peculiar tetrapod Sclerothorax hypselonotusfrom the Middle Buntsandstein (Olenekian) of north−central Germany has emerged that reveals the anatomy of the skull and anterior postcranial skeleton in detail. Despite differences in preservation, all previous plus the new finds of Sclerothorax are identified as belonging to the same taxon. Sclerothorax is characterized by various autapomorphies (subquadrangular skull being widest in snout region, extreme height of thoracal neural spines in mid−trunk region, rhomboidal interclavicle longer than skull). Despite its peculiar skull roof, the palate and mandible are consistent with those of capitosauroid stereospondyls in the presence of large muscular pockets on the basal plate, a flattened edentulous parasphenoid, a long basicranial suture, a large hamate process in the mandible, and a falciform crest in the occipital part of the cheek. In order to elucidate the phylogenetic position of Sclerothorax, we performed a cladistic analysis of 18 taxa and 70 characters from all parts of the skeleton. According to our results, Sclerothorax is nested well within the higher stereospondyls, forming the sister taxon of capitosauroids. Palaeobiologically, Sclerothorax is interesting for its several characters believed to correlate with a terrestrial life, although this is contrasted by the possession of well−established lateral line sulci.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ontogeny of a new cyrtosymboline trilobite from the Famennian of Morocco
Autorzy:
Loresey-Aubril, R
Feist, R.
Powiązania:
https://bibliotekanauki.pl/articles/20463.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
trilobite
cyrtosymboline trilobite
Famennian
Trilobita
ontogenesis
Proetoidea
Cyrtosymbolinae
protaspis
remains
Morocco
paleontology
Opis:
Abundant trilobite remains were recovered from late mid−Famennian marlstones from various sites in Eastern Tafilalet, southeast Morocco. All belong to a single taxon previously identified as Cyrtosymbole (Waribole) prima. This taxon is designated the type species of Osmolskabole gen. nov. A redefinition of this species, including the description of newly discovered, disarticulated exuviae both in limestone and silicified state of preservation, is given. In particular, silicified sclerites of various sizes allow the first complete growth series of a cyrtosymboline proetid to be presented. The close morphological resemblance of its protaspid stages to known proetoid larvae emphasizes the homogeneity of the early ontogeny in this superfamily. The Famennian proetoid anaprotaspis is also of comparable size to that of other Devonian proetoid larvae. However, their size−range is much less than that observed in Carboniferous larvae. This suggests that the survival of proetoid trilobites at the Frasnian−Famennian Kellwasser crisis did not result from a modification of the developmental strategy, as it might have been the case at the terminal Devonian extinction event. Moreover, O. prima possesses a plectrum from the metaprotaspid to the mid meraspid periods. This implies that the natant hypostomal condition is not steadily acquired early in the ontogeny of the Proetida. Thus we preclude the use of this character in the diagnosis of this order.
Źródło:
Acta Palaeontologica Polonica; 2005, 50, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trilobites from the latest Frasnian Kellwasser crisis in North Africa [Mrirt, Central Moroccan Meseta]
Autorzy:
Feist, R
Powiązania:
https://bibliotekanauki.pl/articles/20541.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
trilobite
fauna
Frasnian
Trilobita
location
Kellwasser crisis
biogeography
Africa
Morocco
paleontology
Opis:
Latest Frasnian trilobites are recorded for the first time from North Africa. They occur in oxygenated limestones between the Lower and Upper Kellwasser horizons at Bou Ounabdou near Mrirt, central Moroccan Meseta. The faunas are very close to the contemporaneous associations in European sections both by their taxonomic composition and by patterns of evolutionary behavior towards eye reduction. Two new taxa are described: Gondwanaspis mrirtensis gen. et sp. nov., which is the last known representative of the Odontopleuridae before its extinction at the base of the Upper Kellwasser horizon, and Pteroparia ziegleri maroccanica subsp. nov., a geographical variant of the nominal subspecies from Sessacker in the Rhenish Slate Mountains.
Źródło:
Acta Palaeontologica Polonica; 2002, 47, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New material of a derived ornithomimosaur from the Upper Cretaceous Nemegt Formation of Mongolia
Autorzy:
Bronowicz, R.
Powiązania:
https://bibliotekanauki.pl/articles/21203.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
ornithomimosaur
Upper Cretaceous
Cretaceous
Nemegt Formation
Mongolia
Dinosauria
Ornithomimidae
Anserimimus
paleontology
new species
Anserimimus planinychus
Opis:
New material of an ornithomimid from the Late Cretaceous deposits of Tsagan Khushu (Gobi Desert, Mongolia) is described. The material includes a partial axial skeleton, and hind and forelimb elements. The specimen is similar to Anserimimus planinychus from nearby Bugin Tsav locality in having ventrally flat, long, almost straight manual unguals. The new specimen differs from A. planinychus in the length of the penultimate manual phalanx II−2, which is only slightly shorter than Ph III−3, in a considerably lesser alae of the manual unguals, and in the height/width ratio of the proximal articular surfaces. The material suggests presence of third, hitherto unknown ornithomimid from the Nemegt Formation.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A giant skull of the temnospondyl Xenotosuchus africanus from the Middle Triassic of South Africa and its ontogenetic implications
Autorzy:
Damiani, R
Powiązania:
https://bibliotekanauki.pl/articles/21570.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Temnospondyli
Triassic
paleontology
ontogenesis
Africa
Middle Triassic
variation
temnospondyl form
Xenotosuchus africanus
South Africa
skull
Opis:
A previously unreported large skull of the mastodonsaurid temnospondyl Xenotosuchus africanus, from the Cynognathus Assemblage Zone (Early to Middle Triassic) of the Beaufort Group, Karoo Basin of South Africa, is described. The species is plesiomorphic in most aspects of its cranial anatomy, and only one autapomorphy is tentatively identified herein, namely contact between the left and right exoccipitals posterior to the parasphenoid. The new specimen permits recognition of a growth series for X. africanus from sub−adult (all previously known specimens) to fully adult (new specimen) stages. Ontogenetic changes associated with this include changes in skull proportions, and changes in the morphology of the lacrimal flexure, frontal, postfrontal, cultriform process and body of the parasphenoid, and the transvomerine tooth row.
Źródło:
Acta Palaeontologica Polonica; 2008, 53, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Moles [Talpidae] from the late Middle Miocene of South Germany
Autorzy:
Ziegler, R
Powiązania:
https://bibliotekanauki.pl/articles/21675.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Myxomygale gracilis
Leptoscaptor robustior
Middle Miocene
Mammalia
Leptoscaptor bavaricum
Talpidae
Germany
mole
Tenuibrachiatum storchi
paleontology
Opis:
The moles from the South German fissure fillings Petersbuch 6, 10, 18, 31, 35, 48 include 14 species, four of which are new: Leptoscaptor bavaricum gen. et sp. nov., Leptoscaptor robustior gen. et sp. nov., Myxomygale gracilis sp. nov. and Tenuibrachiatum storchi gen. et sp. nov. Most samples are characterised by their high species diversity. Talpa minuta is the most common species in nearly all samples. Leptoscaptor is characterised by a slender humerus and by the loss of lower antemolars. It is interpreted as a Miocene offshoot of the Scalopini. Myxomygale gracilis represents the latest record of the genus. Tenuibrachiatum storchi has a slender humerus and one lower incisor is lost. The species is structurally ancestral to the extant Urotrichus. The genus Pseudoparatalpa Lopatin, 1999 is considered a synonym of Paratalpa. The talpids of the Petersbuch fissures are in line with a Middle Miocene correlation of MN 7+8 as already indicated by the cricetids. The remains of desmans in the Petersbuch 6 fissure filling indicate the proximity of water. The presence of Urotrichini in nearly all samples, albeit scanty, suggests a forestal environment within the range of the owls, which preyed on them.
Źródło:
Acta Palaeontologica Polonica; 2003, 48, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differential preservation of the Upper Cretaceous ammonoid Anagaudryceras limatum with corrugated shell in Central Hokkaido, Japan
Autorzy:
Wani, R
Powiązania:
https://bibliotekanauki.pl/articles/21872.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Hokkaido
fossil record
Japan
Ammonoidea
Cretaceous
Upper Cretaceous
paleoecology
Anagaudryceras limatum
corrugation
paleontology
ammonoid
Opis:
The taphonomy of the Upper Cretaceous ammonite Anagaudryceras limatum differs from associated ammonites in the same horizon. This differential taphonomy is reconstructed based on fragmentation patterns and structural property of the corrugated shells of their body chamber parts. The characteristic preservation of isolated body chamber parts with corrugations is commonly observed in A. limatum from the upper Turonian of the Oyubari area, central Hokkaido, Japan. This preservation probably results from the differential internal structural properties of the hollow body chamber and septated phragmocone as well as the peculiar corrugation on body chamber of the present species: (1) fracturing along the corrugations against bending force is easier than flat material, because of the concentration of force on the tops or bottoms of corrugations, and (2) high durability against compressive forces. The separated body chamber parts were resistant to being squashed and broke into pieces due to the durability of corrugations against compressive force. The statistic test on the fossil assemblage suggests that selective destruction did not affect the fidelity of species composition and relative abundance of the studied fossil assemblage. Molluscan death assemblages in marine systems consistently show strong fidelity to relative abundances in the live community, suggesting that there was an Anagaudryceras−dominant ammonoid community during the late Turonian in the Oyubari area.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cambrian microfossils from glacial erratics of King George Island, Antarctica
Autorzy:
Wrona, R
Powiązania:
https://bibliotekanauki.pl/articles/22565.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
skeletal fossil
Antarctic
Australia
Middle Cambrian
Early Cambrian
microfossil
Cape Melville Formation
Cambrian
paleontology
Early Miocene
King George Island
Opis:
Limestone erratics in the Early Miocene glacio−marine Cape Melville Formation of King George Island, West Antarctica, have yielded Early and Middle Cambrian small skeletal fossils (SSF) accompanied by calcified cyanobacteria, archaeocyath and spiculate sponges, trilobites and echinoderms. The SSF assemblage comprises disarticulated sclerites of chancelloriids, halkieriids, tommotiids, lapworthellids, palaeoscolecids, hyolithelminths, lingulate brachiopods, helcionelloid molluscs, hyoliths, and bradoriids. All 24 described species are common to Antarctica and Australia. Most are recorded here from Antarctica for the first time, including Shetlandia multiplicata gen. et sp. nov. and two new species Byronia? bifida and Hadimopanella staurata. The lithological and fossil contents of the boulders are almost identical with autochthonous assemblages from the Shackleton Limestone in the Argentina Range and Transantarctic Mountains. Cambrian outcrops around the Weddell Sea are a plausible source of the erratics. The fauna is closely similar to that from the uppermost Botomian Wilkawillina Limestone in the Flinders Ranges and Parara Limestone on Yorke Peninsula, and Toyonian Wirrealpa and Aroona Creek Limestones in the Flinders Ranges, as well as the Ramsay Limestone on Yorke Peninsula, all in the Arrowie and Stansbury Basins of South Australia. These very similar faunal and facies successions for Antarctica and Australia strongly support their common biotic and sedimentary evolution on the same margin of a greater Gondwana supercontinent throughout the Early Cambrian.
Źródło:
Acta Palaeontologica Polonica; 2004, 49, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Graptolodendrum mutabile n.gen., n.sp. - an aberrant dendroid graptolite
Graptolodendrum mutabile n.gen., n.sp. - aberrantny graptolit dendroidowy
Graptolodendrum mutabile n.gen., n.sp. - aberrantnyjj dendroidnyjj graptolit
Autorzy:
Kozlowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/22590.pdf
Data publikacji:
1966
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
Graptolodendrum mutabile
new genus
new species
dendroid graptolite
graptolite
Polska
Dendroidea
Middle Ordovician
Ordovician
Źródło:
Acta Palaeontologica Polonica; 1966, 11, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New species of megaspores from the Trias of Poland
Nowe gatunki megaspor z triasu Polski
Novye vidy megaspor iz triasa Pol’shi
Autorzy:
Fuglewicz, R.
Powiązania:
https://bibliotekanauki.pl/articles/23161.pdf
Data publikacji:
1977
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new species
megaspore
paleontology
Otynisporites
Bothriotriletes
species list
Polska
Triassic
Źródło:
Acta Palaeontologica Polonica; 1977, 22, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phylogeny, palaeoecology, and invasion of non-marine waters by the late Miocene hemicytherid ostracod Tyrrhenocythere from Lake Pannon
Autorzy:
Pipik, R
Powiązania:
https://bibliotekanauki.pl/articles/23418.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
phylogenesis
Miocene
ostracod
Late Miocene
invasion
Ostracoda
Hemicytherinae
Lake Pannon
hemicytherid ostracod
marginal pore canal
paleoecology
non-marine water
paleontology
Tyrrhenocythere
Opis:
Species of the ostracod genus Tyrrhenocythere were found in sediments at the western margin of the Danube Basin, dated as Pannonian zone MN9/MN10 of the late Miocene, together with the euryhaline ostracods Euxinocythere, Loxoconcha, Cyprideis, Hemicytheria, Amplocypris, and Paratethyan Candoninae. Sandy and clayey deposits intercalated with lignite seams, as well as the ostracod assemblages, reflect oscillations of Lake Pannon water level and salinity, from freshwater to pliohaline. Tyrrhenocythere most probably evolved by phyletic transformation from Hemicytheria. The hinge and the central muscle scars of Tyrrhenocythere are plesiomorphic characters and the two genera differ in the arrangement of the marginal pore canals (MPC). The transformation of simple, straight and thin MPC in Hemicytheria to polyfurcate MPC in Tyrrhenocythere can be observed in sympatric and contemporaneous populations in Lake Pannon. On the basis of orna− mentation, T. pezinokensis with heavily calcified valves bearing distinct ornamentation could be a descendent of ribbed and heavily calcified Hemicytheria and possibly represents an extinct lineage, while the lightly calcified T. transitivum sp. nov., T. rastislavi sp. nov., and T.sp. 1, and T. sp. 2 are possibly related to reticulated and punctate Hemicytheria. This model assumes that more than one Hemicytheria lineage transformed their arrangement of MPC, and suggests that Tyrrhenocythere is a polyphyletic genus. After the retreat of Lake Pannon, Tyrrhenocythere species immigrated, together with other ostracod and molluscan fauna, into the Dacian Basin and Eastern Paratethys. Later, in the uppermost Messinian, they colonised the western Mediterranean. Late Miocene and Pliocene Tyrrhenocythere are found in brackish or mixed brackish/freshwater taphocoenoses, but the Pleistocene examples also adapted to freshwater/oligohaline lacus− trine environment (Griffiths et al. 2002: 252). While salinity ranges of Tyrrhenocythere have shifted, toward freshwater since the late Miocene, temperature preference did not change. The mean annual air temperature of the Pannonian (15.6–21.7℃) is close to the temperature preference of living Tyrrhenocythere, with mean annual temperature 12 to 16℃. Two new species, T. rastislavi, and T. transitivum are described.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lower Cretaceous ammonites from Sierra del Rosario (western Cuba)
Dolnokredowe amonity Sierra Del Rosario (zachodnia Kuba)
Ammonity nizhnego mela Sierra del’ Rosario (zapadnaja Kuba)
Autorzy:
Myczynski, R.
Powiązania:
https://bibliotekanauki.pl/articles/20331.pdf
Data publikacji:
1977
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
Cretaceous
Lower Cretaceous
ammonite
Karsteniceras polieri
Crioceras pinarensis
Acrioceras rosariensis
Pleurohoplites machini
Sierra del Rosario Biosphere Reserve
Cuba
Źródło:
Acta Palaeontologica Polonica; 1977, 22, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The phylogenetic position of the ornithischian dinosaur Stenopelix valdensis from the Lower Cretaceous of Germany and the early fossil record of Pachycephalosauria
Autorzy:
Butler, R J
Sullivan, R.M.
Powiązania:
https://bibliotekanauki.pl/articles/21353.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Cretaceous
Dinosauria
ornithischian dinosaur
fossil
paleontology
Pachycephalosauria
Ornithischia
Germany
phylogenetic position
Marginocephalia
Lower Cretaceous
dinosaur
Stenopelix valdensis
Opis:
The holotype of Stenopelix valdensis is the most completely known dinosaur specimen from the “Wealden” (Lower Cretaceous) of northwestern Germany, but its phylogenetic position has remained highly controversial. Most recent authors have suggested affinities with the ornithischian clade Marginocephalia, and most commonly to the marginocephalian subclade Pachycephalosauria. A pachycephalosaurian identity would make Stenopelix the only confirmed pre−Late Cretaceous member of this clade, breaking up an extensive ghost lineage which extends to the inferred origin of Pachycephalosauria in the Middle–Late Jurassic. Based upon re−examination of the holotype we here review the characters that have previously been used to assign Stenopelix to either Pachycephalosauria or Ceratopsia. All of these characters are problematic, being based upon inaccurate anatomical interpretations, or having more widespread distributions within Ornithischia than previously realised. We conclude that although the overall anatomy of Stenopelix is consistent with marginocephalian affinities, there is insufficient evidence to support referral to either Pachycephalosauria or Ceratopsia; we consider Stenopelix ?Marginocephalia. A brief review indicates that there is no compelling fossil evidence for pachycephalosaurs prior to the Late Cretaceous.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 1; 21-34
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new genus of Norian involutinid foraminifers: Its morphological, biostratigraphic, and evolutionary significance
Autorzy:
Rigaud, S.
Martini, R.
Rettori, R.
Powiązania:
https://bibliotekanauki.pl/articles/21780.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new genus
Norian involutinid foraminifer
foraminifer
morphology
biostratigraphy
evolutionary significance
Foraminifera
strengthening
shortened lamella
symbiosis
Triassic
lamella
paleontology
Opis:
The Late Triassic was a time of pronounced radiation in several groups of foraminifers. The rapid evolutionary processes in the Suborder Involutinina caused particularly high diversification of these aragonitic foraminifers, which became a key group for Upper Triassic biostratigraphy. Among them, Triasina hantkeni and Triasina oberhauseri are regarded as the most precise guide fossils. However, while these species are widely used, a poor documentation of the detailed test struc− ture of T. oberhauseri has resulted in misidentifications. The exceptional preservation and abundance of Triasina oberhauseri in the Upper Triassic deposits of the Black Marble Quarry (Wallowa terrane, Oregon, USA) has allowed us to make the first detailed observations of its coiling, innermost structure and lamellae arrangement and to recognize mor− phological features that were either wrongly interpreted or not described in the original systematic definition of the spe− cies. In this paper, we demonstrate that the species possesses characteristics that hamper its assignment to Triasina and we propose a new genus, Aulosina, to accommodate this taxon. Placing emphasis on the accuracy of the morphological de− scription, the diagnosis and the systematic definition of the species are here improved. The identification of innovative features in Aulosina oberhauseri (strengthenings, shortened lamellae) highlights new evolutionary trends for the lineage of Involutinina that have proved useful for the establishment of phylogenetic links between involutinid genera and for un− derstanding the evolutive steps leading to the formation of inner−pillars in tubular foraminifers. The increasing complex− ity of Involutinina representatives at the end of the Triassic, notably marked by the appearance of internal structures in Triasininae, leads us to regard them as probable symbiont−bearing foraminifers.
Źródło:
Acta Palaeontologica Polonica; 2013, 58, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New data on the dentition of the scincomorphan lizard Polyglyphanodon sternbergi
Autorzy:
Nydam, R L
Cifelli, R.L.
Powiązania:
https://bibliotekanauki.pl/articles/22344.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Polyglyphanodontinae
dentition
Polyglyphanodon sternbergi
Late Cretaceous
scincomorphan lizard
Squamata
lizard
North America
paleontology
Opis:
Polyglyphanodon sternbergi Gilmore, 1940 is a large−bodied lizard from the Late Cretaceous of North America distinguished by its transversely oriented, interlocking teeth. Initially the teeth of P. sternbergi were described as smooth and blade−like, but recent discoveries of new specimens from the type locality and re−examination of the original material indicate that the chisel−like teeth of P. sternbergi have small, irregular serrations along the blades. These serrations are similar in size to those found on the teeth of the modern herbivorous lizard Iguana iguana and were likely used in a similar manner to crop vegetation, but was also capable of a degree of oral food processing due to the transverse orientation and interlocking arrangement of the dentition of P. sternbergi. Additionally, the presence of transversely oriented teeth with V−shaped blades in the anterior portion of the tooth row of P. sternbergi represents an additional shared characteristic in tooth structure between P. sternbergi and Dicothodon moorensis, Bicuspidon numerosus, and Peneteius aquilonoius; all transversely−tooth polyglyphandontine lizards from the Cretaceous of North America. It appears that the unique dentitions of Polyglyphanodon sternbergi (large teeth with transverse, serrated blades) and Peneteius aquilonius (small teeth with mammal−like specializations) present by the end of the Cretaceous were derived from a bicuspid, transversely oriented precursor tooth with a V−shaped blade.
Źródło:
Acta Palaeontologica Polonica; 2005, 50, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł

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