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Late Cretaceous gastropod egg capsules from the Netherlands preserved by bioimmuration

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Zaton M., Taylor P. D., Jagt J. W. M.

Acta Palaeontologica Polonica

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2013

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tom 58

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nr 2

Clusters of gastropod egg capsules, inferred to be of neritoids and attached to the inner shell wall of the ultimate whorl of a large volutid gastropod, are here recorded from the upper Nekum Member (Maastricht Formation; late Maastrichtian) of the ENCI−Heidelberg Cement Group quarry, St Pietersberg (Maastricht, southeast Netherlands). Because the aragonitic shell of the volutid has dissolved, the outlines of the egg capsules are now revealed on the steinkern of indurated biocalcarenite, having been subsequently overgrown by cheilostome bryozoan colonies and preserved as mould bioimmurations. This represents the first example of gastropod eggs preserved through bioimmuration, as well as the first record of gastropod eggs from the Cretaceous.

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New data on anatomy of the Late Cretaceous multituberculate mammal Catopsbaatar

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Kielan-Jaworowska Z., Hurum J. H., Currie P. J., Barsbold R.

Acta Palaeontologica Polonica

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2002

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tom 47

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nr 3

The Gobi Desert is famous for providing one of the worlds best preserved Cretaceous terrestrial faunas, including dinosaurs and mammals. Beginning with the Central Asiatic Expeditions in the 1920s, through the Polish−Mongolian Expeditions in the 1960s–1970s, Soviet−Mongolian Expeditions in 1970s, and finally the Mongolian Academy−American Museum Expeditions in the 1990s–2000s, the number of complete skulls (see Kielan−Jaworowska et al. 2000 for review) of Cretaceous mammals often associated with postcranial skeletons, found in Mongolia increased to several hundred. In addition to these professional expeditions, there have been other types of trips to Mongolia, also aimed at collecting fossils. The Nomadic Expeditions Company in USA organizes one of these, and has made trips to Mongolia since 1996. During the 1999 Nomadic Expedition, a skull associated with parts of the postcranial skeleton of the multituberculate mammal Catopsbaatar catopsaloides was found. The specimen is more complete than others previously known of this species and brings new data on multituberculate anatomy and ontogenetic variation. In this note we discuss the new data on the structure of C. catopsaloides; the details of its anatomy will be described in subsequent papers by the two first authors.

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Halszka Osmolska [1930-2008]

100%

Borsuk-Bialynicka M., Maryanska T.

Acta Palaeontologica Polonica

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2008

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tom 53

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nr 2

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Origin and significance of Late Cretaceous bioevents: Examples from the Cenomanian

84%

Wilmsen M.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

Palaeontological events, documented by widespread beds or thin intervals of strata with either unusual (“exotic”) or acmes of common faunal elements are a characteristic feature of Upper Cretaceous epicontinental shelf sediments in NW Europe. Their importance in stratigraphic calibration has early been recognized and these “bioevents” are widely used as correlation tools. Furthermore, it appears that there is a genetic link between sequence and event stratigraphy as most of the “classic” bioevents developed during specific intervals of a 3rd−order depositional sequence. Early transgressive bioevents (ETBs) are subdivided into two subtypes, i.e., the lag and migration subtype. The lag subtype corresponds to the transgressive surface and develops in response to winnowing and relative enrichment of robust biogenic hardparts. Taphonomic alteration and time−averaging are important features. The migration subtype is related to the disappearance of physical or ecological barriers that triggered faunal migrations. Despite their onlapping character, most ETBs are quasi−isochronous, and their preservation potential is usually high. Thus, they are very useful stratigraphic markers. Maximum flooding bioevents (MFBs) represent autochthonous biogenic concentrations with relatively low shell densities. They are related to habitat stability and ecospace expansion, and develop by population blooms of taxa well adapted to the special maximum flooding conditions of the wide epicontinental shelf of NW Europe (e.g., low food availability). Cenomanian MFBs of NW Europe are not time−averaged and may comprise stratigraphically more expanded intervals with gradational lower and upper boundaries. Their often wide palaeogeographic extent associated with very high chances of preservation results in an excellent inter−basinal correlation potential. Late highstand bioevents (LHBs) are local to regional shell concentrations deposited as a result of increasing winnowing of fines and reworking by storms, currents and waves during late highstands. LHBs usually consist of paucior even monospecific skeletal concentrations with a high degree of fragmentation. Simple shell beds related to a single (storm) event, and composite (multiple−event) shell beds are recognized. LHBs share some features of ETBs, but lack of time−averaging, are laterally restricted and have low preservation potential. Thus, their importance in interbasinal correlation is poor. The time scales of Cenomanian bioevents range through several orders of magnitude (hours–days in LHB storm event concentrations to ~100 kyr in MFBs). In terms of position within sequences, the three bioevent types correspond to shell concentrations recognized in Mesozoic–Cenozoic formations around the world. Shell beds with similar positions within cycles as well as comparable sedimentologic and taphonomic characteristics have also been described from high−frequency sequences and parasequences, suggesting that the formational processes of shell beds operate in base−level controlled sedimentary cycles of different hierarchies (i.e., 3rd−up to 7th−order).

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First record of a basal neoceratopsian dinosaur from the Late Cretaceous of Kazakhstan

84%

Averianov A., Sues H. D.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 3

553-556

The oldest known ceratopsians come from the Late Jurassic of China (Zhao et al. 1999; Xu et al. 2006). During the Early Cretaceous, the basal ceratopsian Psittacosaurus was among the most common dinosaurs in Asia but more derived basal neoceratopsians were quite rare on that continent (Xu et al. 2002; Makovicky and Norell 2006). Basal neoceratopsians became more abundant in the Late Cretaceous of Mongolia and China, although they are not known in this region from the latest Cretaceous (You and Dodson 2004; Alifanov 2008). In contrast, basal neoceratopsians are rare during the Early Cretaceous in North America but became common and diverse during the Campanian and Maastrichtian (You and Dodson 2004; Chinnery and Horner 2007). Little is known about the evolutionary history of this group in more inland regions of what are now Kazakhstan and adjoining countries. Asiaceratops documents the presence of basal neoceratopsians in the Cenomanian of Uzbekistan (Nessov et al. 1989). Here we report on the first record of a basal neoceratopsian in the Late Cretaceous of Kazakhstan, based on two cranial bones from the Turonian Zhirkindek Formation in the northeastern Aral Sea region.

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Late Cretaceous crest-bearing shrimps from the Sahel Alma Lagerstatte of Lebanon

84%

Audo D., Charbonnier S.

Acta Palaeontologica Polonica

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2013

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tom 58

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nr 2

Decapod crustaceans are the most diverse group of fossil invertebrates from the Upper Cretaceous Sahel Alma Lagerstätte (Lebanon, Middle East). They are mainly represented by abundant crest−bearing shrimps which were first described as Penaeus libanensis. We review this species applying the new systematic nomenclature and we propose a more complete description based on 54 unpublished specimens. This review leads to the erection of Palaeobenthesicymus gen. nov. and to the new combination Palaeobenthesicymus libanensis that is the oldest record of the family Benthesicymidae. A neotype is herein designated. Detailed comparisons with extant analogues suggest that the crest bearing shrimps inhabited relatively deep water settings most probably exceeding 150 m, at the transition between the lower circalittoral and the upper bathyal zones, under dysphotic or aphotic conditions.

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Ammonite faunal dynamics across bio-events during the mid- and Late Cretaceous along the Russian Pacific coast

84%

Jagt-Yazykova E. A.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

The present paper focuses on the evolutionary dynamics of ammonites from sections along the Russian Pacific coast during the midand Late Cretaceous. Changes in ammonite diversity (i.e., disappearance [extinction or emigration], appearance [origination or immigration], and total number of species present) constitute the basis for the identification of the main bio−events. The regional diversity curve reflects all global mass extinctions, faunal turnovers, and radiations. In the case of the Pacific coastal regions, such bio−events (which are comparatively easily recognised and have been described in detail), rather than first or last appearance datums of index species, should be used for global correlation. This is because of the high degree of endemism and provinciality of Cretaceous macrofaunas from the Pacific region in general and of ammonites in particular.

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The oldest Brazilian snakes from the Cenomanian (early Late Cretaceous)

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Hsiou A. S., Albino A. M., Medeiros M. A., Santos R. A. B.

Acta Palaeontologica Polonica

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2014

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tom 59

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nr 3

South American Mesozoic snake diversity is mostly represented by genera from the Cenomanian (Najash), Santonian– Campanian (Dinilysia), and Campanian–Maastrichtian (Alamitophis, Patagoniophis, Rionegrophis, and Australophis) of Patagonia, Argentina. In this paper, we describe a new snake genus and species, Seismophis septentrionalis, from the Cenomanian (early Late Cretaceous) of the Alcântara Formation, Maranhão, northeastern Brazil. The new snake comprises a posteriormost trunk vertebra and possibly a poorly preserved midtrunk vertebra. Both vertebrae share small size, zygosphene moderately thick with a rectilinear roof, absence of paracotylar foramina, presence of parazygantral foramina, and strongly marked parasagittal ridges of the neural arch. The new snake is here considered of uncertain systematic affinities, but probably close to the limbed snake Najash rionegrina. Although the material is very fragmentary and the systematic assignment is still unresolved, this snake represents the oldest, as well as probably the most primitive snake from Brazil.

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Therian femora from the Late Cretaceous of Uzbekistan

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Chester S. G. B., Sargis E. J., Szalay F. S., Archibald J. D., Averianov A. O.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 1

Femora referable to metatherians and eutherians recovered from the Bissekty Formation, Dzharakuduk, Kyzylkum Desert, Uzbekistan (90 Mya), are described. Fourteen isolated specimens were sorted based on size and morphology into groups that likely correspond to the species level or higher. Groups were then tentatively assigned to taxa known from teeth, petrosals, and/or other postcrania at these localities. One distal femur of a small arboreal metatherian, and several eutherian distal femora that probably represent zhelestids and/or zalambdalestids were identified. With the exception of one proximal femur that is similar in some aspects to the zalambdalestid Barunlestes, and a previously described multituberculate specimen, all other proximal femora from the Bissekty Formation exhibit a metatherian−like morphology. The dental record currently suggests the presence of twelve eutherian species and only one metatherian at Dzharakuduk, whereas the humeral and crurotarsal evidence supports the presence of at least two or four metatherian species, respectively. Given the sample size of the proximal femora, the morphological diversity present, and the overwhelming presence of eutherians at these localities, it is highly unlikely that the overwhelming majority of proximal femora actually represent metatherians. Therefore, this sample may suggest that the metatherian proximal femoral condition is primitive for Theria and that some eutherian taxa (probably including Zhelestidae, which are dentally most abundant at these localities) retain this condition.

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New specimens of the multituberculate mammal Uzbekbaatar from the Late Cretaceous of Uzbekistan

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Averianov A. O., Archibald J. D.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 2

Uzbekbaatar Kielan−Jaworowska and Nessov, 1992 is among the rarest mammals and the only multituberculate in the diverse, eutherian dominated Bissekty (Turonian) and Aitym (?Coniacian) local faunas, Kyzylkum Desert, Uzbekistan. New material from the Bissekty local fauna, suggests that only one multituberculate species, Uzbekbaatar kizylkumensis Kielan−Jaworowska and Nessov, 1992 is present in the Bissekty fauna. A newly collected p4 is better preserved than the holotype and demonstrates presence of the posterolabial cusp in the p4 of Uzbekbaatar. New material of Uzbekbaatar is consistent with placement of this taxon within the basal cimolodontan “Paracimexomys group.”

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Lower incisor in zalambdalestid mammals [Eutheria] and its phylogenetic implications

84%

Fostowicz-Frelik L., Kielan-Jaworowska Z.

Acta Palaeontologica Polonica

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2002

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tom 47

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nr 1

Relationships of the specialized eutherian family Zalambdalestidae (Late Cretaceous, Asia) have long been debated. Beginning with suggestion of Van Valen (1964) and including the recent phylogenetic analysis of Archibald et al. (2001), a possible close relationship of Zalambdalestidae to Glires (Lagomorpha + Rodentia) has been repeatedly suggested (but see Meng and Wyss 2001). One of the characteristics of Glires is the structure of the lower incisor, which is enlarged and open−rooted. An open−rooted incisor has been documented in the oldest known zalambdalestid, Kulbeckia, but structure of this tooth has remained unknown for the Mongolian representatives of this family, Zalambdalestes and Barunlestes. Here we present evidence on the presence of an open−rooted first lower incisor in Zalambdalestes lechei and Barunlestes butleri; we argue, however, that structure of this incisor does not necessarily indicate relationship of Zalambdalestidae to Glires.

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New data on the dentition of the scincomorphan lizard Polyglyphanodon sternbergi

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Nydam R. L., Cifelli R. L.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 1

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.

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Counting premolars in early eutherian mammals

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Cifelli R. L.

Acta Palaeontologica Polonica

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2000

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tom 45

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nr 2

The primitive number of premolars for most eutherian groups is four. A growing number of Cretaceous taxa, however, had five. Regardless of the hypothesis used to explain the discrepancy, or what the primitive condition was, it is generally agreed that the middle (third) tooth of five-premolared taxa is the one not represented in mammals that have only four premolars. Hence the current practice of labeling the teeth as the first through fifth and the first through fourth, depending on how many teeth are observed in the jaw, results in incorrect implied homologies for the last two premolars of the series. Given the long-standing tradition of referring to the premolars as the first through fourth, for most eutherian groups, together with the uncertainties involved in interpreting the difference, the most practical solution is to refer to the disputed tooth by a neutral term, 'Px', as advocated several decades ago.

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Late Cretaceous sharks Cretoxyrhina and Cardabiodon from Montana, USA

84%

Siverson M., Lindgren J.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 2

The middle part of the Cretaceous represents a time of high diversity and rapid rates of dental evolution in lamniform sharks. Several species had a very wide spatial distribution with recorded occurrences in both hemispheres. We have examined isolated teeth of Cretoxyrhina and Cardabiodon from eastern Russia, Mangyshlak in Kazakhstan, and the Western Interior of the USA. The material indicates that samples of isolated teeth of the two genera have high potential in intercontinental correlation of the upper Albian to mid−Turonian interval in mid−palaeolatitude deposits, poor in other age−diagnostic fossil groups. The utilization of these lamniforms in mid−Cretaceous biostratigraphy is currently hampered by the nearly total absence in the literature of well illustrated, well dated and sufficiently large samples of isolated teeth of the two genera. As a first step towards the establishment of an intercontinental elasmobranch zonation for mid−Cretaceous strata in temperate palaeo−regions, we describe and illustrate samples of teeth of Cardabiodon venator sp. nov. and Cretoxyrhina mantelli from the lower middle Turonian Collignoniceras woollgari regulare Zone in the Fairport Member of the Carlile Shale in east−central Montana, USA. These samples could serve as reference points for future biostratigraphic studies of Cretoxyrhina and Cardabiodon. The extinction of Cretoxyrhina may be diachronous, as regional last appearance data range from the upper Santonian (Marsupites testudinarius Zone) in Western Australia to the uppermost lower Campanian (informal Belemnellocamax mammillatus zone; a lateral equivalent to the German Gonioteuthis quadrata gracilis/Belemnitella mucronata Zone) in southern Sweden.

15

67%

Arbour V. M., Lech-Hernes N. L., Guldberg T. E., Hurum J. H., Currie P. J.

Acta Palaeontologica Polonica

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2013

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tom 58

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nr 1

A Mongolian ankylosaurid specimen identified as Tarchia gigantea is an articulated skeleton including dorsal ribs, the sacrum, a nearly complete caudal series, and in situ osteoderms. The tail is the longest complete tail of any known ankylosaurid. Remarkably, the specimen is also the first Mongolian ankylosaurid that preserves impressions of the keratinous scales overlying the bony osteoderms. This specimen provides new information on the shape, texture, and ar− rangement of osteoderms. Large flat, keeled osteoderms are found over the pelvis, and osteoderms along the tail include large keeled osteoderms, elongate osteoderms lacking distinct apices, and medium−sized, oval osteoderms. The specimen differs in some respects from other Tarchia gigantea specimens, including the morphology of the neural spines of the tail club handle and several of the largest osteoderms.

Ograniczanie wyników

Late Cretaceous gastropod egg capsules from the Netherlands preserved by bioimmuration

New data on anatomy of the Late Cretaceous multituberculate mammal Catopsbaatar

Halszka Osmolska [1930-2008]

Origin and significance of Late Cretaceous bioevents: Examples from the Cenomanian

First record of a basal neoceratopsian dinosaur from the Late Cretaceous of Kazakhstan

Late Cretaceous crest-bearing shrimps from the Sahel Alma Lagerstatte of Lebanon

Ammonite faunal dynamics across bio-events during the mid- and Late Cretaceous along the Russian Pacific coast

The oldest Brazilian snakes from the Cenomanian (early Late Cretaceous)

Therian femora from the Late Cretaceous of Uzbekistan

New specimens of the multituberculate mammal Uzbekbaatar from the Late Cretaceous of Uzbekistan

Lower incisor in zalambdalestid mammals [Eutheria] and its phylogenetic implications

New data on the dentition of the scincomorphan lizard Polyglyphanodon sternbergi

Counting premolars in early eutherian mammals

Late Cretaceous sharks Cretoxyrhina and Cardabiodon from Montana, USA

Biostratigraphy and palaeoecology of the Late Cretaceous foraminiferids at Krzyworzeka Stream Section [Subsilesian Unit, Polish Outer Carpathians]

Marsupials from the Late Cretaceous of Uzbekistan

Stagodontid marsupials from the Late Cretaceous of Canada and their systematic and functional implications

A revision of 'pediomyid' marsupials from the Late Cretaceous of North America

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

An ankylosaurid dinosaur from Mongolia with in situ armour and keratinous scale impressions