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Niedzwiedzki, GrzegorzORCID iD iconorcid.org/0000-0002-4775-5254
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Publications (10 of 53) Show all publications
Sulej, T. & Niedzwiedzki, G. (2019). An elephant-sized Late Triassic synapsid with erect limbs. Science, 363(6422), 78-80
Open this publication in new window or tab >>An elephant-sized Late Triassic synapsid with erect limbs
2019 (English)In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 363, no 6422, p. 78-80Article in journal (Refereed) Published
Abstract [en]

Here, we describe the dicynodont Lisowicia bojani, from the Late Triassic of Poland, a gigantic synapsid with seemingly upright subcursorial limbs that reached an estimated length of more than 4.5 meters, height of 2.6 meters, and body mass of 9 tons. Lisowicia is the youngest undisputed dicynodont and the largest nondinosaurian terrestrial tetrapod from the Triassic. The lack of lines of arrested growth and the highly remodeled cortex of its limb bones suggest permanently rapid growth and recalls that of dinosaurs and mammals. The discovery of Lisowicia overturns the established picture of the Triassic megaherbivore radiation as a phenomenon restricted to dinosaurs and shows that stem-group mammals were capable of reaching body sizes that were not attained again in mammalian evolution until the latest Eocene.

Place, publisher, year, edition, pages
AMER ASSOC ADVANCEMENT SCIENCE, 2019
National Category
Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-375225 (URN)10.1126/science.aal4853 (DOI)000455315800064 ()30467179 (PubMedID)
Funder
Swedish Research Council, 2017-05248
Available from: 2019-01-29 Created: 2019-01-29 Last updated: 2019-01-29Bibliographically approved
Qvarnström, M., Vikberg Wernström, J., Piechowski, R., Talanda, M., Ahlberg, P. E. & Niedzwiedzki, G. (2019). Beetle-bearing coprolites possibly reveal the diet of a Late Triassic dinosauriform. Royal Society Open Science, 6(3), Article ID 181042.
Open this publication in new window or tab >>Beetle-bearing coprolites possibly reveal the diet of a Late Triassic dinosauriform
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2019 (English)In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 3, article id 181042Article in journal (Refereed) Published
Abstract [en]

Diets of extinct animals can be difficult to analyse if no direct evidence, such as gut contents, is preserved in association with body fossils. Inclusions from coprolites (fossil faeces), however, may also reflect the diet of the host animal and become especially informative if the coprolite producer link can be established. Here we describe, based on propagation phase-contrast synchrotron microtomography (PPC-SRμCT), the contents of five morphologically similar coprolites collected from two fossil-bearing intervals from the highly fossiliferous Upper Triassic locality at Krasiejow in Silesia, Poland. Beetle remains, mostly elytra, and unidentified exoskeleton fragments of arthropods are the most conspicuous inclusions found in the coprolites. The abundance of these inclusions suggests that the coprolite producer deliberately targeted beetles and similar small terrestrial invertebrates as prey, but the relatively large size of the coprolites shows that it was not itself a small animal. The best candidate from the body fossil record of the locality is the dinosauriform Silesaurus opolensis Dzik, 2003, which had an anatomy in several ways similar to those of bird-like neotheropod dinosaurs and modern birds. We hypothesize that the beak-like jaws of S. opolensis were used to efficiently peck small insects off the ground, a feeding behaviour analogous to some extant birds.

Keywords
coprolites, palaeoecology, Dinosauromorpha, beetle elytra, insectivore
National Category
Geosciences, Multidisciplinary Other Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:uu:diva-383880 (URN)10.1098/rsos.181042 (DOI)000465470300008 ()31031991 (PubMedID)
Funder
Swedish Research Council, 2017-05248
Available from: 2019-06-11 Created: 2019-06-11 Last updated: 2019-06-11Bibliographically approved
Mörs, T., Niedzwiedzki, G., Crispini, L., Laeufer, A. & Bomfleur, B. (2019). First evidence of a tetrapod footprint from the Triassic of northern Victoria Land, Antarctica. Polar Research, 38, Article ID 3438.
Open this publication in new window or tab >>First evidence of a tetrapod footprint from the Triassic of northern Victoria Land, Antarctica
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2019 (English)In: Polar Research, ISSN 0800-0395, E-ISSN 1751-8369, Vol. 38, article id 3438Article in journal (Refereed) Published
Abstract [en]

Here, we report on a tetrapod footprint from the Transantarctic Basin in the far north of Victoria Land, which marks the first record of terrestrial vertebrates for this region. The single specimen derives from a previously unknown lithological unit of Middle or Late Triassic age of the Beacon Supergroup in the Helliwell Hills in the central Rennick Glacier area. It differs in both size and morphology clearly from Middle Triassic trackway types from the upper Fremouw Formation of the Queen Alexandra Range in southern Victoria Land, and likely represents a primitive amniote, procolophonid or therapsid. The footprint is the third evidence of fossil vertebrate trackways in Antarctica.

Place, publisher, year, edition, pages
TAYLOR & FRANCIS LTD, 2019
Keywords
Beacon Supergroup, Helliwell Hills, ichnotaxon, Procolophonichnium, Rennick Glacier, Transantarctic Basin
National Category
Other Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:uu:diva-390290 (URN)10.33265/polar.v38.3438 (DOI)000474229100001 ()
Funder
Swedish Research Council, 2012-5323
Available from: 2019-09-09 Created: 2019-09-09 Last updated: 2019-09-09Bibliographically approved
Scholze, F., Golubev, V. K., Niedzwiedzki, G., Schneider, J. W. & Sennikov, A. G. (2019). Late Permian conchostracans (Crustacea, Branchiopoda) from continental deposits in the Moscow Syneclise, Russia. Journal of Paleontology, 93(1), 72-97
Open this publication in new window or tab >>Late Permian conchostracans (Crustacea, Branchiopoda) from continental deposits in the Moscow Syneclise, Russia
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2019 (English)In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 93, no 1, p. 72-97Article in journal (Refereed) Published
Abstract [en]

The Moscow Syneclise on the East European Platform is an important area for the study of the continental biota of late Permian to Early Triassic age in continuous sections. This study attempts a taxonomic description of the late Permian conchostracan fauna of this area. The rich, new material was collected, bed by bed, during geological and paleontological excavations of lacustrine and fluvial deposits of the Obnora Formation and Vokhma Formation of the late Permian Zhukovian Regional Stage near the towns of Vyazniki and Gorokhovets. The conchostracan fauna of the Zhukovian Regional Stage consists predominantly of Pseudestheria and less frequently of Palaeolimnadiopsis. In the earliest Triassic Vokhmian Regional Stage, a more diverse fauna including Euestheria, Magniestheria, Cornia, Palaeolimnadiopsis, and Rossolimnadiopsis was already recorded. The preliminary taxonomic determination of the pseudestheriids from the Zhukovian Regional Stage is intended to serve as a prerequisite for future studies of late Permian conchostracan biostratigraphy on the regional to interregional scale.

National Category
Other Earth and Related Environmental Sciences Geology
Identifiers
urn:nbn:se:uu:diva-375842 (URN)10.1017/jpa.2018.58 (DOI)000455719500005 ()
Funder
German Research Foundation (DFG), SCHN408/22-1
Available from: 2019-02-01 Created: 2019-02-01 Last updated: 2019-02-01Bibliographically approved
Elgh, E., Pienkowski, G. & Niedzwiedzki, G. (2019). Pterosaur track assemblages from the Upper Jurassic (lower Kimmeridgian) intertidal deposits of Poland: Linking ichnites to potential trackmakers. Palaeogeography, Palaeoclimatology, Palaeoecology, 530, 32-48
Open this publication in new window or tab >>Pterosaur track assemblages from the Upper Jurassic (lower Kimmeridgian) intertidal deposits of Poland: Linking ichnites to potential trackmakers
2019 (English)In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 530, p. 32-48Article in journal (Refereed) Published
Abstract [en]

Two distinct tetrapod track assemblages, dominated by pterosaur traces, are reported from Upper Jurassic (lower Kimmeridgian, Hypselocyclum Zone) tidal flat carbonate deposits exposed in Wierzbica Quarry, 20 km south of Radom, Poland. The pterosaur tracks, tentatively assigned to Pteraichnus isp. are well preserved as a positive hyporelief in intertidal facies. Some are preserved with anatomical details (e.g., skin, claw or digital pad impressions) and quality sufficient to make preliminary ichnotaxonomic assignment. Nearly all collected specimens are larger than most other pterosaurian ichnites of the Late Jurassic age, thus adding to the growing diversity of pterosaur traces known from this time period. Morphometrical and anatomical analyses show that ctenochasmatoids or possibly non-pterydactyloid monofenestratans or rhamphorhynchids were most likely the trackmakers. Anatomical comparisons give new insights into the morphology of the pes of pterydactyloids and the most closely related non-pterodactyloids which may be correlated with a niche expansion into marginal marine and lacustrine environments by Middle and Late Jurassic pterosaurs. The palaeoenvironmental interpretation as tidal flat is confirmed by presence of vertically accreted tidal bundles, each representing deposition in one tidal cycle. Most likely then, this was one of the environments frequented by these pterosaurs and other small tetrapods. The wider palaeoecological significance of the tracks is evaluated in the context of other similar reports from the Late Jurassic of Europe, Africa and North America.

Place, publisher, year, edition, pages
ELSEVIER, 2019
Keywords
Pteraichnus, Trace fossils, Ctenochasmatoids, Rhamphorhynchids, Marginal marine
National Category
Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-393323 (URN)10.1016/j.palaeo.2019.05.016 (DOI)000478712100003 ()
Available from: 2019-09-27 Created: 2019-09-27 Last updated: 2019-09-27Bibliographically approved
Qvarnström, M., Ahlberg, P. & Niedzwiedzki, G. (2019). Tyrannosaurid-like osteophagy by a Triassic archosaur. Scientific Reports, 9, Article ID 925.
Open this publication in new window or tab >>Tyrannosaurid-like osteophagy by a Triassic archosaur
2019 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 925Article in journal (Refereed) Published
Abstract [en]

Here we present evidence for osteophagy in the Late Triassic archosaur Smok wawelski Niedzwiedzki, Sulej and Dzik, 2012, a large theropod-like predator from Poland. Ten medium to large-sized coprolites are matched, by their dimensions and by association with body fossils and footprints, to S. wawelski. The coprolites contain fragments of large serrated teeth as well as up to 50 percent by volume of bone fragments, with distinct fragmentation and angularity, from several prey taxa. This suggests pronounced osteophagy. Further evidence for bone-crushing behaviour is provided by isolated worn teeth, bone-rich regurgitalites (fossil regurgitates) and numerous examples of crushed or bite-marked dicynodont bones, all collected from the same bone-bearing beds in the Lipie Slaskie clay-pit. Several of the anatomical characters related to osteophagy, such as a massive head and robust body, seem to be shared by S. wawelski and the tyrannosaurids, despite their wide phylogenetic separation. These large predators thus provide evidence of convergence driven by similar feeding ecology at the beginning and end of the age of dinosaurs.

National Category
Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-377342 (URN)10.1038/s41598-018-37540-4 (DOI)000457128700002 ()30700743 (PubMedID)
Funder
Swedish Research Council, 2017-05248Knut and Alice Wallenberg Foundation
Available from: 2019-02-25 Created: 2019-02-25 Last updated: 2019-02-25Bibliographically approved
Piechowski, R., Niedzwiedzki, G. & Talanda, M. (2019). Unexpected bird-like features and high intraspecific variation in the braincase of the Triassic relative of dinosaurs. Historical Biology, 31(8), 1065-1081
Open this publication in new window or tab >>Unexpected bird-like features and high intraspecific variation in the braincase of the Triassic relative of dinosaurs
2019 (English)In: Historical Biology, ISSN 0891-2963, E-ISSN 1029-2381, Vol. 31, no 8, p. 1065-1081Article in journal (Refereed) Published
Abstract [en]

Silesaurus opolensis Dzik, 2003 from the Late Triassic (late Carnian) of Poland is a key taxon for understanding the evolution of early dinosaurs. High intraspecific variation observed in the S. opolensis braincase brings caution in taxonomic and diversity studies of early dinosauromorphs. The external and internal osteology of three almost complete braincases of S. opolensis show that this taxon shares several similarities with other early dinosauriforms, which supports a close relationship among these forms. However, the paroccipital processes of S. opolensis are directed ventrally like in birds, reaching the level of the ventral margin of the basioccipital condyle. In dinosauromorphs, these processes usually have an almost horizontal orientation (presumed to be the plesiomorphic condition). Modifications observed in birds and S. opolensis have resulted in the dorsoventral expansion of M. complexus and M. depressor mandibulae, which occupy the dorsolateral part of the posterior side of the skull. In adult birds, these muscles act strongly on the initial upstroke of the head during drinking. Therefore, the inferred condition of these muscles in S. opolensis may imply that Silesauridae evolved toward bird-like feeding behaviour.

Place, publisher, year, edition, pages
TAYLOR & FRANCIS LTD, 2019
Keywords
Silesaurus, dinosauriforms, archosauria, neuroanatomy, Carnian, Late Triassic
National Category
Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-391276 (URN)10.1080/08912963.2017.1418339 (DOI)000476682900007 ()
Available from: 2019-08-22 Created: 2019-08-22 Last updated: 2019-08-22Bibliographically approved
Qvarnström, M. & Niedźwiedzki, G. (2018). A new charophyte flora from the Upper Triassic of Skane (Sweden) and implications on biostratigraphy, taphonomy and the palaeoenvironment. Review of Palaeobotany and Palynology, 249, 61-79
Open this publication in new window or tab >>A new charophyte flora from the Upper Triassic of Skane (Sweden) and implications on biostratigraphy, taphonomy and the palaeoenvironment
2018 (English)In: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 249, p. 61-79Article in journal (Refereed) Published
Abstract [en]

The record of fossil charophytes from Sweden was previously restricted to the Ladinian-earliest Carnian Falsterbo Formation. Here, we present a charophyte assemblage from the Upper Triassic KAgerod Formation exposed at the Balteberga Gorge (Sickle, southern Sweden) from the perspectives of taxonomy, taphonomy, palaeoecology and biostratigraphy. The microfossils originate from an interval of reddish sandy mudstone and are represented by rare fossil thalli, calcium carbonate encrustations of thalli and numerous calcified fructifications, called gyrogonites. The assemblage is relatively diverse, comprising six species belonging to four genera of the family Porocharaceae (Auerbachichara cf. rhaetica, Porochara sp., Stellatochara germanica, Stellatochara aff. subsphaerica, Stenochara aff. donetziana, Stenochara aff. kisielevskyi). Both the sedimentological context and the preservation of the charophyte remains point to an autochthonous origin for the charophyte-bearing strata. An autochthonous origin together with the habitat of modern charophytes, infer that the charophyte interval was deposited in shallow ephemeral pond or lake in a terrestrial setting. Their occurrence is also indicative of low amount of nutrients and the numerous thalli encrustations suggest a rather alkaline water composition. Some of the described species (Auerbachichara cf. rhaetica and Stellatochara aff. subsphaerica) are useful for biostratigraphical correlations which attributes the assemblage to the Auerbachichara rhaetica Range zone (sensu Bilan, 1991) in the proposed Germanic Triassic charophyte zonation. This range zone is assigned to a latest Carnian to late Norian age, strengthened by an interlayering with rocks containing a characteristic assemblage of palynomorphs (Corollina meyeriana subzone a and b) in the Upper Triassic of the Polish part of the Germanic Basin. The findings of the first Triassic thalli further strengthen the suggestion that the early Mesozoic fossil record of charophytes is not solely composed of oospores and gyrogonites. A better understanding of vegetative fossil remains (silicified thalli and encrustations) of charophytes may provide important future palaeoecological implications and links between recent and extinct forms. Our findings also provide evidence that charophyte occurrences in the ICagerod Formation are strictly controlled by palaeoenvironmental factors. (C) 2017 Elsevier B.V. All rights reserved.

Place, publisher, year, edition, pages
Elsevier, 2018
Keywords
Gyrogonites, Porocharaceae, Carnian, Norian, Scandinavia
National Category
Earth and Related Environmental Sciences Ecology Botany
Identifiers
urn:nbn:se:uu:diva-346881 (URN)10.1016/j.revpalbo.2017.11.005 (DOI)000424184500006 ()
Funder
Swedish Research Council, 2017-05248
Available from: 2018-03-28 Created: 2018-03-28 Last updated: 2018-03-28Bibliographically approved
Niedzwiedzki, G. & Budziszewska-Karwowska, E. (2018). A new occurrence of the Late Triassic archosaur Smok in southern Poland. Acta Palaeontologica Polonica, 63(4), 703-712
Open this publication in new window or tab >>A new occurrence of the Late Triassic archosaur Smok in southern Poland
2018 (English)In: Acta Palaeontologica Polonica, ISSN 0567-7920, E-ISSN 1732-2421, Vol. 63, no 4, p. 703-712Article in journal (Refereed) Published
Abstract [en]

Two isolated teeth, a dorsal vertebra, fragments of a humerus and femur, a fragmentary pubic "boot" and part of an ischium shaft, identified here as belonging to a large predatory archosaur were discovered in the Upper Triassic site at Marciszow near Zawiercie (southern Poland). Comparisons of the new fossils from Marciszow with the dorsal vertebrae, pubic "boot", ischium and femur of the theropod-like Smok wawelski from Lisowice (Silesia) reveal that the two taxa are very similar. Nevertheless, due to the lack of more diagnostic elements (e.g., braincase or cranial elements), we prefer to consider all described specimens from Marciszow as Smok sp. Smok sp. shares a low mound-like, anterior trochanter with trochanteric shelf on the femur, a massive pubic "boot" with a distinct depression (= bevelled area), and a transversely lenticular ischium shaft in cross-section with S. wawelski. Some observed characters of the dorsal vertebra (e.g., lack of some lamina, shape and position of zygapophyses), however, are different from S. wawelski and may also suggest that the new findings represent a second species of the genus in the Upper Triassic of Poland. The discovery of Smok sp. at Marciszow is significant because it is the second example of the co-occurrence of this genus with: (i) bones of a large dicynodont; and (ii) record of gnawed tetrapod bones. The discovery of Smok sp. and the lack of significant morphologic divergence from S. wawelski suggest that this taxon is the only large-bodied predator currently known from the Upper Triassic of Poland. This new evidence expands the record of the genus and contributes, in some measure, to our knowledge of the stratigraphical distribution of large predatory archosaurs from the Polish Upper Triassic bone-bearing levels.

Place, publisher, year, edition, pages
INST PALEOBIOLOGII PAN, 2018
Keywords
Diapsida, Archosauromorpha, Archosauria, Late Triassic, Poland, Silesia
National Category
Other Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:uu:diva-372915 (URN)10.4202/app.00505.2018 (DOI)000452781900007 ()
Funder
Swedish Research Council, 2017-05248
Available from: 2019-01-10 Created: 2019-01-10 Last updated: 2019-01-10Bibliographically approved
Skrzycki, P., Niedzwiedzki, G. & Talanda, M. (2018). Dipnoan remains from the Lower-Middle Triassic of the Holy Cross Mountains and northeastern Poland, with remarks on dipnoan palaeobiogeography. Palaeogeography, Palaeoclimatology, Palaeoecology, 496, 332-345
Open this publication in new window or tab >>Dipnoan remains from the Lower-Middle Triassic of the Holy Cross Mountains and northeastern Poland, with remarks on dipnoan palaeobiogeography
2018 (English)In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 496, p. 332-345Article in journal (Refereed) Published
Abstract [en]

Here we present a revision of dipnoans from the Middle-Upper Buntsandstein and the Lower Muschelkalk (Lower-Middle Triassic) of the Holy Cross Mountains (southeastern Poland) and from the Middle Buntsandstein of northeastern Poland. Two genera are identified: Arganodus and Ptychoceratodus. Specimens resemble synchronous species from the European part of Russia. It is the first Middle Triassic finding of Arganodus worldwide. Ptychoceratodus is reported for the first time from the Lower Triassic of Poland. It is its oldest known occurrence in Europe. The Holy Cross Mountains stands between the area of European Russia and the Central European Basin which were both inhabited by Arganodus and Ptychoceratodus in the Early-Middle Triassic. Resulting from a summary of palaeobiogeographic data of these two genera their distributional patterns are hypothesized herein. In the Early Triassic both genera often co-occurred in many regions. Starting from the Middle Triassic their ranges split into two almost separate ones. They reflect the palaeolatitudinal belts in the Late Triassic with Arganodus in the northern tropic belt and Ptychoceratodus along the palaeolatitudes 30 degrees.

Keywords
Lungfish, Tooth plates, Buntsandstein, Muschelkalk, Palaeobiogeography
National Category
Other Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:uu:diva-351618 (URN)10.1016/j.palaeo.2018.01.049 (DOI)000428973000025 ()
Funder
Knut and Alice Wallenberg Foundation
Available from: 2018-06-13 Created: 2018-06-13 Last updated: 2018-06-13Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0002-4775-5254

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