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The Late Jurassic Slottsmøya Member Lagerstätte on Spitsbergen preserves a diverse array of marine reptiles, including four named taxa of ophthalmosaurid ichthyosaurs. One of these, Palvennia hoybergeti, is based on the single holotype... more
The Late Jurassic Slottsmøya Member Lagerstätte on Spitsbergen preserves a diverse array of marine reptiles, including four named taxa of ophthalmosaurid ichthyosaurs. One of these, Palvennia hoybergeti, is based on the single holotype specimen (SVB 1451) with an incomplete skull. A newly discovered specimen (PMO 222.669) with a disarticulated but largely complete skull and anterior postcranium is described, which considerably expands our knowledge of this taxon. Two additional
new ophthalmosaurid specimens with pectoral girdles from the same member are described. The taxonomic utility of the ophthalmosaurid pectoral girdle is contentious, and an assessment of seven pectoral girdles from the Slottsmøya Member provides a basis for addressing this question via a 2D landmark principal component analysis of baracromian coracoids. The analysis reveals a taxonomic
signal in the coracoids but also highlights the degree of individual variation. Commonly used phylogenetic characters do not fully encapsulate the degree of variation seen in coracoids and in some cases combine analogous features.
Jaw elements of Omphalosaurus sp. are described from the Early Triassic (Spathian) of Marmierfjellet, Spitsbergen. The elements are from the Grippia and the Lower Saurian niveaus in the Vendomdalen Member of the Vikinghøgda Formation. In... more
Jaw elements of Omphalosaurus sp. are described from the Early Triassic (Spathian) of Marmierfjellet, Spitsbergen. The elements are from the Grippia and the Lower Saurian niveaus in the Vendomdalen Member of the Vikinghøgda Formation. In the Grippia niveau a bonebed was excavated in 2014–15 and a large number of ichthyopterygian elements were recovered. Together with the omphalosaurian jaw elements a collection of large vertebral centra were recognized as different from the smaller Grippia centra and more than 200 large vertebral centra are referred to Ichthyopterygia indet. and tentatively assigned to regions of the vertebral column. We refrain from further assignment due to the systematic position and the difficulty of defining criteria for recognizing postcranial elements of Omphalosaurus.
A new specimen of Phalarodon from the Middle Triassic Botneheia Formation on Svalbard, although not complete, is well preserved with both cranial and postcranial elements. Uncompressed preservation of the rostrum reveals the dental groove... more
A new specimen of Phalarodon from the Middle Triassic Botneheia Formation on Svalbard, although not complete, is well preserved with both cranial and postcranial elements. Uncompressed preservation of the rostrum reveals the dental groove divided by alveolar bone between the teeth. The right opisthotic has a thin and plate-like paroccipital process, a structure which has only been observed in Mixosaurus cornalianus among mixosaurids. The rare preservation of the atlas-axis complex, being nearly complete and articulated, is very similar to that of Phalarodon callawayi. The interclavicle, although not complete, is preserved with detailed structures which have previously not been described in Mixosauridae. Contrary to earlier studies, the shoulder girdle, with an articulated scapula and coracoid, reveals a coracoid facet on the scapula. Using comparative morphological and phylogenetic analyses, similarities between the new specimen and the known species of Mixosauridae are addressed. We assign the new specimen to Phalarodon fraasi. With its uncompressed preservation, the new specimen contributes to the knowledge of our morphology
of the species. This study suggests a reassignment of the specimen PMO 219.250 to the genus Mixosaurus, and opens up for the possibility of Mixosaurus on Svalbard. This would imply a wider geographical distribution of the genus than previously recognised. Additionally, it would prove the coexistence of Mixosaurus and Phalarodon in a shared habitat at the same point in time, a hypothesis that is strengthened by the differences in dentition which reflects separate feeding habits, and thus different niches.
Humeri of Pessopteryx nisseri and vertebrae referred to Cymbospondylus sp. are described from the Lower Saurian niveau at Marmierfjellet, Spitsbergen. This is the most well-preserved Cymbospondylus material described from the Early... more
Humeri of Pessopteryx nisseri and vertebrae referred to Cymbospondylus sp. are described from the Lower Saurian niveau at Marmierfjellet, Spitsbergen. This is the most well-preserved Cymbospondylus material described from the Early Triassic so far, and the first description of new material of Pessopteryx nisseri since the species was established. The taxa are not represented by articulated or overlapping material. Herein, the most diagnostic material of both taxa is described and discussed, and the possibility that there is only one large-sized taxon present is suggested. Several specimens of Ichthyosauria indet. are also described. Comparisons are made to previously described specimens from the Lower Saurian niveau, including the disputed Merriamosaurus hulkei. The Boreal Ocean of Svalbard is of particular interest due to its position at the northern margin of Pangea, between the Early Triassic localities of today’s British Colombia and Nevada, and South China. More than 2000 three-dimensional and disarticulated fragments show that large-sized ichthyosaurs had evolved and were numerous by the Early Triassic.
This is the first time since the collections of Carl Wiman that the Lower Saurian niveau has been systematically sampled and placed in the
modern stratigraphy.
The Grippia bonebed is located at Marmierfjellet in Flowerdalen, Isfjorden area of Spitsbergen. The bonebed occurs in the Vendomdalen Member, Vikinghøgda Formation, Early Triassic (Spathian). It is unique in Spitsbergen because of the... more
The Grippia bonebed is located at Marmierfjellet in Flowerdalen, Isfjorden area of Spitsbergen. The bonebed occurs in the Vendomdalen
Member, Vikinghøgda Formation, Early Triassic (Spathian). It is unique in Spitsbergen because of the richness of chondrichthyans,
osteichthyes, amphibians and ichthyopterygians. This paper focuses on the chondrichthyans with more than 550 chondrichthyan teeth
studied, together with three fin spines and one cephalic spine, assigned to 7 genera and 15 species, 8 of which are new from the Grippia
niveau. The Hybodontiformes represent five of the identified genera, where most of the identified species belong to Hybodus and Acrodus.
Hybodus sasseniensis, previously recorded from the older Dienarian substage, and is now shown to occur in the younger Spathian substage,
and suggested to be the senior synonym of H. rapax. The possibility of Acrodus scaber and A. spitzbergensis being morphospecies, and the
Acrodus genus in general, is further discussed. The occurrence of Hybodus microdus in the material is uncertain since it is shown that the
mesio-distal length of the teeth is much larger than described by Stensiö in 1921. The Neoselachii (modern shark), previously only known from
a fin spine of Nemacanthus from the Triassic of Spitsbergen, is now described from teeth belonging to possibly two new neoselachian species. They are referred to Synechodontiformes 1 and 2, awaiting more material to be processed.
The palaeontology of the Lower to Middle Triassic succession in Spitsbergen has been studied for more than a century and a half. Our ability to properly interpret the evolutionary and ecological implications of the faunas requires precise... more
The palaeontology of the Lower to Middle Triassic succession in Spitsbergen has been studied for more than a century and a half. Our ability to properly interpret the evolutionary and ecological implications of the faunas requires precise stratigraphic control that has only recently become available. Within such a detailed stratigraphic framework, the Spitsbergen fossil material promises to contribute to our understanding of the faunal recovery after the end-Permian mass extinction.
The Agardhfjellet Formation (Middle Jurassic to lowermost Cretaceous) of Svalbard (Norwegian Arctic) is well known for its abundant and unique marine reptile fauna, of ichthyosaurs and plesiosaurs. In an attempt to reconstruct the... more
The Agardhfjellet Formation (Middle Jurassic to lowermost Cretaceous) of Svalbard (Norwegian Arctic) is well known for its abundant and unique marine reptile fauna, of ichthyosaurs and plesiosaurs. In an attempt to reconstruct the palaeoecology and palaeoenvironment of the Agardhfjellet Formation, a study of the invertebrate fauna, geochemistry and stratigraphy was conducted. During this study numerous small vertebrate fossils were encountered. Only a few reports of Jurassic teleost from the Arctic were known previously, from the Agardhfjellet Formation on Svenskøya, Kong Karls Land, described as Leptolepis nathorsti, and at Lardyfjellet, East Spitsbergen. We describe more teleost material from the Kimmeridgian and Volgian of the Agardhfjellet Formation in central Spitsbergen and assign a new age, Kimmeridgian, to the original material. This new material also provides more information on the palaeoecology of the Jurassic of Svalbard, showing that fish were probably common in the pelagic fauna of central Spitsbergen together with the better known cephalopods, and could have been important elements of the diet of the marine reptiles.
Barneboka som er grunnen til at jeg er den jeg er i dag www.barnebokkritikk.no/barneboka-som-er-grunnen-til-at-jeg-er-den-jeg-er-i-dag/ Da jeg var seks år i 1973 var jeg allerede en hyppig gjest på Nedre Eiker bibliotek i Mjøndalen. Jeg... more
Barneboka som er grunnen til at jeg er den jeg er i dag www.barnebokkritikk.no/barneboka-som-er-grunnen-til-at-jeg-er-den-jeg-er-i-dag/ Da jeg var seks år i 1973 var jeg allerede en hyppig gjest på Nedre Eiker bibliotek i Mjøndalen. Jeg var full av grublerier – «hvem er jeg», «hvorfor er jeg akkurat meg og ingen andre», «hvor kommer jeg fra» var spørsmål som surret rundt i hodet mitt. Jeg kunne ikke lese ennå, men ble lest høyt for hver kveld. James Fenimore Coopers cowboy-og
Geo/ogistudenter pa UN!S-kurset AG-323 (sekvensstratigrafi) logger seg gjennom nedre kritt-lagrekken pa U/laberget iVan Ke-ulenjjorden. Den tykke sandsteinsbenken ble avsatt i en tidevannskanal som .ble dannet i en periode hvor kystlinjen... more
Geo/ogistudenter pa UN!S-kurset AG-323 (sekvensstratigrafi) logger seg gjennom nedre kritt-lagrekken pa U/laberget iVan Ke-ulenjjorden. Den tykke sandsteinsbenken ble avsatt i en tidevannskanal som .ble dannet i en periode hvor kystlinjen gradvis trakk seg til bake. UN IS-professor Snorre Olaussen jubler for endelig a ha sett sola gjennom det tykke skydekket. 1 bakgrunnen skimtes den tertir.ere lagrekken. Foto: Sten-Andreas Grundvag
En 95 millioner år gammel blekksprut forteller sin historie med sitt eget blekk. Når du tenker på gammel kunst, er det kanskje romerske statuer eller hulemalerier du ser for deg. Kunst som er laget for lenge siden. Jeg fikk en ide om å... more
En 95 millioner år gammel blekksprut forteller sin historie med sitt eget blekk. Når du tenker på gammel kunst, er det kanskje romerske statuer eller hulemalerier du ser for deg. Kunst som er laget for lenge siden. Jeg fikk en ide om å gjøre det motsatte, altså lage kunst i dag med et gammelt utgangspunkt. Blekksprut på ønskelisten Helt siden jeg så bilde av en fossil blekksprut i 2009, har jeg hatt et slikt fossil på ønskelisten til Naturhistorisk museum sine utstil-linger. De typene av blekkspruter som har harde skall, slik som de utdødde ammonittene og den nålevende perlemorsblekkspruten Nautilus, kan enkelt bli til fossiler. I hvert fall det harde skallet. Andre blekkspruter har kroker av kitin (nesten som det du har i neglene) i armene sine. De kan også bli funnet som fossiler. Men blekkspruter som de åttearmede blekksprutene og akkaren blir som regel aldri til fossiler. De kan ha levd i alle hav i hundrevis av millioner år uten at vi finner et eneste fossil av dem. De bare råtner og blir resirkulert når de dør. Heldigvis finnes det ingen regler uten unntak. Noen få fossilfore-komster i verden har også oppbevaring av bløtvev. Dette skjer bare under helt spesielle forhold under vann, ofte er en total mangel på oksygen i bunnvannet viktig, kanskje også høyt saltinnhold. Vi forstår det faktisk ikke helt. Blekkspruten jeg var ute etter finnes kun i et steinbrudd i Libanon. For 95 millioner år siden var dette en grunn lagune der det yrte av liv. Dyrene som døde og sank ned til bunnen ble forseglet i sedimentene uten at de råtnet. Her er det funnet alt fra beinfisk og haier til reker og maneter. I 2014 fikk jeg en telefon fra en fossilhandler jeg kjenner godt. Mike ringte meg fra en stein-og fossilmesse i Frankrike. Han fortalte at han sto og så på fossilet som sto på min fossilønskeliste. Det var i Foto: Charlotte Bjorå Sugekopper og blekk De neste ukene fikk jeg jevnlig oppdatering av hvordan han pre-parerte fram og limte sammen delene til en hel blekksprut. Det var like spennende hver gang det kom en e-post med nye bilder. Detaljene på dette fossilet var utrolige. Armene viste til og med sugekoppene! Og da jeg endelig fikk fossilet til museet, oppdaget jeg en ting til. På bildene så den mørke ringen med blekksekken helt flat ut. Det var den ikke. Det var masse svart materiale i en stor klump. Det minnet mest om hard asfalt. Jeg visste at noen forskere fra blant annet England og Danmark hadde analysert en slik blekksekk for et par år siden og funnet ut at pigmentene fra blekket var bevart. Her var det masse av det! mange biter, men han trodde det kunne bli komplett. Han kunne kjøpe det og bruke noen uker på å lime det sammen. I mellomtiden snakket jeg med PalVenn, Paleontologisk museums Venner, og de sa seg villige til å finansiere hele prosjektet. Når vi ser naermere på detaljene i fossilet, ser vi både sugekoppene (bildet til venstre) og rester av blekket (bildet til høyre), med pigmenter som fremdeles er bevart etter så mange millioner år! Foto: Mike Bäätjer Det vakre fossilet begynner som et puslespill. Foto: Mike Bäätjer
Hurum, J.H., Roberts, A.J., Dyke, G.J., Grundvåg, S.-A., Nakrem, H.A., Midtkandal, I., Śliwińska, K.K., and Olaussen, S. 2016. Bird or maniraptoran dinosaur? A femur from the Albian strata of Spitsbergen. Palaeontologia Polonica 67,... more
Hurum, J.H., Roberts, A.J., Dyke, G.J., Grundvåg, S.-A., Nakrem, H.A., Midtkandal, I., Śliwińska, K.K., and Olaussen, S. 2016. Bird or maniraptoran dinosaur? A femur from the Albian strata of Spitsbergen. Palaeontologia Polonica 67, 137–147.
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We reexamine a Lower Cretaceous dinosaur tracksite at Boltodden in the Kvalvågen area, on the east coast of Spitsbergen, Svalbard. The tracks are preserved in the Helvetiafjellet Formation (Barremian). A sedimentological characterization... more
We reexamine a Lower Cretaceous dinosaur tracksite at Boltodden in the Kvalvågen area, on the east coast of Spitsbergen, Svalbard. The tracks are preserved in the Helvetiafjellet Formation (Barremian). A sedimentological characterization of the site indicates that the tracks formed on a beach/margin of a lake or interdistributary bay, and were preserved by flooding. In addition to the two imprints already known from the site, we describe at least 34 additional, previously unrecognized pes and manus prints, including one trackway. Two pes morphotypes and one manus morphotype are recognized. Given the range of morphological variation and the presence of manus tracks, we reinterpret all the prints as being from an ornithopod rather than a thero-pod, as previously described. We assign the smaller (morphotype A, pes; morphotype B, manus) to Caririchnium billsarjeanti. The larger (morphotype C, pes) track is assigned to Caririchnium sp., differing in size and interdigital angle from the two described ichnospecies C. burreyi and C. bill-sarjeanti. The occurrence of a quadrupedal, small to medium-sized ornithopod in Svalbard is puzzling , considering the current palaeogeographical reconstructions and that such dinosaur tracks have mainly been described from Europe but not North America. Gold Open Access: This article is published under the terms of the CC-BY 3.0 license.
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J 0 R N H. HURUM Hurum, J.H. 1994. Snout and orbit of Cretaceous Asian multitiuberculates studied by serial sections. Acta Palaeontologica Polonica 39, 2, 181-221. The orbital wall in Nemegtbaatar gohiensis and Chulsanbaatar vulgaris,... more
J 0 R N H. HURUM Hurum, J.H. 1994. Snout and orbit of Cretaceous Asian multitiuberculates studied by serial sections. Acta Palaeontologica Polonica 39, 2, 181-221. The orbital wall in Nemegtbaatar gohiensis and Chulsanbaatar vulgaris, from the Late Crrtaceous of the Gobi Desert, Mongolia, comprises a small lacrimal anteriorly , large orbital process of the frontal dorsally, orbitosphenoid posteriorly and maxilla ventrally. Nemegtbaatar also posesses an orbital process of the palatine ventrally, not recognized in Chulsanbaatar. Large frontal sinuses of both taxa are interpreted as related to lack of the sagittal crest. Other anatomical characters found in this study, such as orbital process of the frontal, ossified turbinals, ossified ethmoid and vomer, frontal, sphenoidal and maxillary sinuses, and the presence of the orbital process of palatine in Nemegtbaatar suggest a close relationship of multituberculates to monotremes and therian mammals. By the new data obtained from the serial sections the diagnostic character: orbital process of the palatine absent in Multituberculata, is no longer valid. Ossified ethmoid and maxillary turbinals, characteristic for Monotremata, Vincekstes, Marsupialia and Placentalia, are also present in Multituberculata. The precence of a cribiform plate and the precence of an ossified plate of ethmoid in Multituber-c~data is shared with Monotremata, Vincelestes, Marsupialia and Placentalia. K e y w o r d s:
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Denne våren har mange kost seg med å bli skremt av Den sjette utryddelsen av Elizabeth Kolbert (sjå s. 105). Det er all grunn til å ta det ho skriv på alvor. Men samstundes syner tittelen hennar at det har vore helvete på jord tidlegare.... more
Denne våren har mange kost seg med å bli skremt av Den sjette utryddelsen av Elizabeth Kolbert (sjå s. 105). Det er all grunn til å ta det ho skriv på alvor. Men samstundes syner tittelen hennar at det har vore helvete på jord tidlegare. Livet har gått gjennom mange større og mindre utrenskingar. Fem av desse har sidan 1982 vore rekna som dei fem store, men det har vore mange mindre masseutdøyingar òg. Det er ikkje eingong sik-kert at dei «fem store» er dei fem største. No er det jo slik at normaltilstanden for ein art er å vera utdøydd. At artar oppstår og forsvinn er ein lovmessig konsekvens av evo-lusjonen. Nokre artar utviklar seg til nye artar, slik Homo sapiens har erstatta artane vi har utvikla oss frå. Andre artar og grupper har vist seg å vera evolusjonaere blindspor. Dei har bukka under for endringar i det miljøet dei hadde tilpassa seg. Dei kan ha blitt utkonkurrert av nye artar, eller ikkje klart å tilpassa seg gradvise endringar i det fysiske miljøet. Men ved det som vert kalla mas-seutdøyingar, endrar miljøet seg så hurtig at svaert mange artar ikkje klarar å tilpassa seg og vert borte. Den mest kjende masseut-ryddinga er utdøyinga som skjedde mellom kritt og paleogen (og som derfor vert kalla kritt-paleogen-utdøyinga) for 66 millionar år sidan, og mange veit at ein meteor som slo ned utanfor Mexico var ei av årsakene til at dinosaurane døydde ut. Eit meteornedslag høyrest jo hurtig nok ut det, men det var jo ikkje slik at når meteo-ritten slo ned, fekk alle dinosaurane kvar sin bit av den i knollen og strauk med. Sjølv om meteoritten hadde god hjelp av ein serie samtidige vulkanutbrot i India til å fylla atmosfaeren med støv og oske, reknar vi med at utdøyingsperioden varte rundt 1 million år. Når kritt/paleogen-utdøyinga er den hurtigaste av dei fem store, skjønar vi at dette med masseutdøyingar er seige greier. Men så er det svaere ting på gang òg. Dystre spådomar seier at ved midten av dette århundret kjem halvparten av artane på jorda til å vera utrydda, dei fleste som fylgje av menneskeleg aktivitet. Likevel har Det høyrest jo veldig trist og leit ut med alle desse artane som berre forsvinn, og på ein måte er det jo det. Når dei fyrst er borte, er dei borte for evig og alltid. Men kvar av masseutdøyingane er som ei omvend trakt, der dei artane som klarar seg gjennom nålauget, vert opphav til ei mengd nye artar som kan breia seg utover kloden. Dei fyrste millionane år etter ei utrydding er det ganske ville evolusjo-naere tilstandar, livet kjem ut på den andre sida av katastrofen som ein full mann på sykkel. Nokre artar og grupper er raskt ute med å tilpassa seg, og kan verta dominerande over kortare eller lengre periodar. Men etter kvart kan dei oppleva å bli pressa ut av artar som brukar lengre tid på å tilpassa seg, men som gjer det betre. Nye katastrofar, nye muligheiter, med andre ord. Og det skal vi vera kisteglade for. Som kjent har vi alle ei ubroten rekkje av for-gjengarar heilt tilbake til livet oppstod, og vi stammar dermed frå artar som kom seg gjennom alle dei fem store og ei mengd mindre små utdøyingar. Dermed kan vi ordna masseutdøyingane kronolo-gisk på ein meir positiv måte, ved å peika ut kven vi kan takka for at det er vi som er her i dag og ikkje trilobittane: Ordovicium-silur: fiskane som firbeinte virveldyr (tetrapo-dane) stamma frå Slutten av devon: fortsatt fisk, men nokon av dei har begynt å få bryst-og bukfinner som likna på lemer, og kunne kanskje kravla seg opp på land Perm-trias: cynodontane, ei landlevande gruppe pattedyrlig-nende reptil som var oppstått relativt kort tid før masseutdøy-inga Slutten av trias: cynodontane vart kraftig redusert av utdøy-ingane, men vi og alle andre pattedyr stammar frå dei få små som klarte seg Kritt-paleogen: små spissmusliknande pattedyr som ikkje nølte med å utvikla seg til ei lang rekkje artar som kunne fylla dei ledige nisjene som dei landlevande dinosaurane etterlot seg Så hurra for masseutdøyingar og dei fem omvende traktene, utan dei ville ikkje vi vore her! The history of life is a story of massive removal followed by differentiation within a few surviving stocks, not the conventional tale of steadily increasing excellence, complexity, and diversity. vi endå eit stykke att før vi karrar oss inn blant topp fem. Dette er tabelltoppen så langt vi kjenner den i dag, rangert etter omfang: 1. Perm-trias: 96 % av alle artar i havet, 70 % av landlevande arter Tidspunkt: ca. 252 mill. år sidan Varigheit: usikkert Årsak: vulkanutbrot, klimaforverring Farvel til: sjøskorpionar, trilobittar, pigghaiar, blastoidar, det meste faktisk 2. Ordovicium-silur: 85 % Tidspunkt: ca. 440 mill. år sidan Varigheit: 10 mill. år Årsak: endring i havnivå og istid Farvel til: rundt 100 havlevande familiar 3. Slutten av devon: 82 % Tidspunkt: ca. 365 mill. år sidan Varigheit: 3 mill. år Årsak: kaldare klima og oksygenfattig hav Farvel til: mange fiskeartar, korallar, trilobittar og armføtingar 4. Slutten av trias: 76 % Tidspunkt: ca. 210 mill. år sidan Varigheit: 3–4 mill. år Årsak: vulkanutbrot og global oppvarming Farvel til: conodontar, mange landlevande artar som gav plass til dinosaurane 4. Kritt-paleogen: 76 % Tidspunkt: 66 mill. år sidan Varigheit: 1 mill. år Årsak: meteoritt og vulkanutbrot Farvel til: alle dinosaurar som ikkje kunne fly
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Norge er ikke det landet man først tenker på når det gjelder dinosaurer. Men faktisk har vi noen verdenssensasjoner. På Svalbard ble verdens første dinosaurspor i Arktis funnet, og i Nordsjøen ligger verdens dypeste dinosaurfunn.
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The limb posture in early mammals is a matter of controversy. Kielan−Jaworowska and Gambaryan presented arguments for a sprawling posture in multituberculates, based mainly on three characters of the hind limbs (deep pelvis, mediolateral... more
The limb posture in early mammals is a matter of controversy. Kielan−Jaworowska and Gambaryan presented arguments for a sprawling posture in multituberculates, based mainly on three characters of the hind limbs (deep pelvis, mediolateral diameter of the tibia larger than the craniocaudal, and position of MtV, which fits the peroneal groove on the calcaneus and is not aligned with the axis of tuber calcanei). Here we present two more arguments for sprawling hind limbs in early mammals. One is the presence of an os calcaris, supporting the probably venomous spur in hind legs of docodontans, multituberculates, eutriconodontans, and " symmetrodontans " , similar to those of extant monotremes. We argue that early mammals (except for boreosphenidans) had sprawling limb posture and venomous spur; acquisition of the parasagittal stance was apparently characteristic only of boreosphenidans, in which the spur has not been found. The second argument is based on taphonomic evidence from lacustrine conditions (e.g., Early Cretaceous Jehol Biota), in which the mamma− lian skeletons, except for boreosphenidans (Sinodelphys and Eomaia), have been preserved compressed dorso−ventrally, suggesting sprawling stance. In similar conditions of the Eocene Messel Biota the skeletons of boreosphenidan mammals (except for bats and pangolins) are preserved lying on flanks, suggesting parasagittal stance. Sereno argued that forelimbs in multituberculates were parasagittal, based on the stated presence of a ventrally facing glenoid, a mobile shoulder joint, and an elbow joint with enhanced flexion−extension capability. However, these characters are not unequivocally indica− tive of parasagittalism. We demonstrate that the structure of the distal end of the multituberculate humerus is condylar, with no tendency for developing a trochlea. We reconstruct multituberculates and other early mammals with sprawling stance in resting position as plantigrade.
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2003. Skull structure and evolution in tyrannosaurid dinosaurs. Acta Palaeonto− logica Polonica 48 (2): 227–234. Tyrannosauridae can be subdivided into two distinct subfamilies—the Albertosaurinae and the Tyrannosaurinae. Previ− ously... more
2003. Skull structure and evolution in tyrannosaurid dinosaurs. Acta Palaeonto− logica Polonica 48 (2): 227–234. Tyrannosauridae can be subdivided into two distinct subfamilies—the Albertosaurinae and the Tyrannosaurinae. Previ− ously recognized subdivisions Aublysodontinae and Shanshanosaurinae are rejected because they are based on insuffi− cient material and juvenile specimens. Our results are based upon a phylogenetic analysis using PAUP program (Swofford 1999) of 77 skull characters and seven genera (Albertosaurus, Alioramus, Daspletosaurus, Gorgosaurus, Nanotyrannus, Tarbosaurus, and Tyrannosaurus); with Allosaurus as outgroup. Of the 77 characters used, more than half were parsimony informative. A single most parsimonious tree was obtained with the Tree Length being 88. The analysis of cranial characters and comparison of postcranial features reveal that Tarbosaurus bataar is not the sister taxon of Tyrannosaurus rex (contra Holtz 2001). Their similarities are partially due to the fact that both are extremely large ani− mals. Thus, Tarbosaurus should be considered a genus distinct from Tyrannosaurus.
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Hurum, J.H. and Sabath, K. 2003. Giant theropod dinosaurs from Asia and North America: Skulls of Tarbosaurus bataar and Tyrannosaurus rex compared. Acta Palaeontologica Polonica 48 (2): 161–190. The skull of a newly prepared Tarbosaurus... more
Hurum, J.H. and Sabath, K. 2003. Giant theropod dinosaurs from Asia and North America: Skulls of Tarbosaurus bataar and Tyrannosaurus rex compared. Acta Palaeontologica Polonica 48 (2): 161–190. The skull of a newly prepared Tarbosaurus bataar is described bone by bone and compared with a disarticulated skull of Tyrannosaurus rex. Both Tarbosaurus bataar and Tyrannosaurus rex skulls are deep in lateral view. In dorsal view, the skull of T. rex is extremely broad posteriorly but narrows towards the snout; in Ta. bataar the skull is narrower (especially in its ventral part: the premaxilla, maxilla, jugal, and the quadrate complex), and the expansion of the posterior half of the skull is less abrupt. The slender snout of Ta. bataar is reminiscent of more primitive North American tyrannosaurids. The most obvious difference between T. rex and Ta. bataar is the doming of the nasal in Ta. bataar which is high between the lacrimals and is less attached to the other bones of the skull, than in most tyrannosaurids. This is because of a shift in the handling of the crushing bite in Ta. bataar. We propose a paleogeographically based division of the Tyrannosaurinae into the Asiatic forms (Tarbosaurus and possibly Alioramus) and North American forms (Daspletosaurus and Tyranno− saurus). The division is supported by differences in anatomy of the two groups: in Asiatic forms the nasal is excluded from the major series of bones participating in deflecting the impact in the upper jaw and the dentary−angular interlocking makes a more rigid lower jaw.
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A section of bone is described from a well core retrieved from a depth of 2615 m MD (measured depth RKB; 2590 m mean sea level) in the Lunde Formation of the Snorre Oil Field, Norwegian North Sea. The specimen is interpreted to be the... more
A section of bone is described from a well core retrieved from a depth of 2615 m MD (measured depth RKB; 2590 m mean sea level) in the Lunde Formation of the Snorre Oil Field, Norwegian North Sea. The specimen is interpreted to be the metaphyseal region of a limb bone showing radial fibro-lamellar tissue of a type described for Plateosaurus from the Late Triassic of Germany. Associated palynomorphs suggest the Norwegian specimen to be from the Early Rhaetian (ca. 202-203 Ma).
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The Mesozoic biotas of Scandinavia have been studied for nearly two centuries. However , the last 15 years have witnessed an explosive advance in research, most notably on the richly fossiliferous Triassic (Olenekian–Carnian) and Jurassic... more
The Mesozoic biotas of Scandinavia have been studied for nearly two centuries. However , the last 15 years have witnessed an explosive advance in research, most notably on the richly fossiliferous Triassic (Olenekian–Carnian) and Jurassic (Tithonian) Lagerstätten of the Norwe-gian Arctic Svalbard archipelago, Late Cretaceous (Campanian) Kristianstad Basin and Vomb Trough of Skåne in southern Sweden, and the UNESCO heritage site at Stevns Klint in Denmark – the latter constituting one of the most complete Cretaceous–Palaeogene (Maastrichtian –Danian) boundary sections known globally. Other internationally significant deposits include earliest (Induan) and latest Triassic (Norian–Rhaetian) strata from the Danish autonomous territory of Greenland, and the Early Jurassic (Sinemurian– Pliensbachian) to Early Cretaceous (Berriasian) rocks of southern Sweden and the Danish Baltic island of Bornholm, respectively. Marine palaeo-communities are especially well documented, and comprise prolific benthic macroinvertebrates, together with pelagic cephalopods, chondrichthyans, actinopterygians and aquatic amniotes (ich-thyopterygians, sauropterygians and mosasauroids). Terrestrial plant remains (lycophytes, spheno-phytes, ferns, pteridosperms, cycadophytes, bennettitaleans and ginkgoes), including exceptionally well-preserved carbonized flowers, are also world famous, and are occasionally associated with faunal traces such as temnospondyl amphibian bones and dinosaurian footprints. While this collective documented record is substantial, much still awaits discovery. Thus, Scandinavia and its Arctic territories represent some of the most exciting prospects for future insights into the spectacular history of Mesozoic life and environments.
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A partial postcranial plesiosaurian skeleton uncovered on Svalbard in the winter of 1930-31 was described and named Tricleidus svalbardensis Persson, 1962. However, the precise geographic location and stratigraphic unit in which the... more
A partial postcranial plesiosaurian skeleton uncovered on Svalbard in the winter of 1930-31 was described and named Tricleidus svalbardensis Persson, 1962. However, the precise geographic location and stratigraphic unit in which the skeleton was found were not published. Recent fieldwork on Svalbard has uncovered two more plesiosaur skeletons that are demonstrated herein to be conspecific with the 1931 taxon. These new specimens, along with recently discovered historic documents produced by the excavation members of the 1930-31 expedition, reveal that the holotype specimen, PMO A 27745, was recovered from the Upper Jurassic Slottsmøya Member of the Agardhfjellet Formation, which is Middle Volgian in age. Collectively, the Svalbard material is neither morphologically nor stratigraphically consistent with the Callovian taxon Tricleidus Andrews, 1909 and is here referred to Colymbosaurus Seeley, 1874 from the Kimmeridge Clay Formation (Kimmeridgian to Tithonian) of the UK.
Eight seasons of fieldwork in the Upper Jurassic black shales of the Slottsmøya Member of the Agardhfjellet Formation (Upper Jurassic; Middle Volgian) in the Arctic archipelago of Svalbard have yielded numerous skeletal remains of... more
Eight seasons of fieldwork in the Upper Jurassic black shales of the Slottsmøya Member of the Agardhfjellet Formation (Upper Jurassic; Middle Volgian) in the Arctic archipelago of Svalbard have yielded numerous skeletal remains of plesiosaurs and ichthyosaurs. Among the new discoveries from the Slottsmøya Member are two very large specimens of short-necked plesiosaurians. Dental and postcranial morphology suggest that they represent a new species of the genus Pliosaurus, a taxon known from several specimens of Kimmeridgian and Tithonian-aged strata in England, France and Russia. Skeletal dimensions of this new taxon suggest that it was one of the largest members of the Pliosauridae and that it possessed comparatively longer front limbs than other known pliosaurids. A morphometric analysis of pliosaurids indicates they had a wide range of interspecific variability in relative paddle lengths compared to body size.
Kielan−Jaworowska, Z., Hurum, J. H., and Badamgarav, D. 2003. An extended range of multituberculate Kryptobaatar and distribution of mammals in the Upper Cretaceous of the Gobi Desert. Acta Palaeontologica Polonica 48 (2) 273-278. The... more
Kielan−Jaworowska, Z., Hurum, J. H., and Badamgarav, D. 2003. An extended range of multituberculate Kryptobaatar and distribution of mammals in the Upper Cretaceous of the Gobi Desert. Acta Palaeontologica Polonica 48 (2) 273-278. The Late Cretaceous multituberculate mammal Kryptobaatar dashzevegi Kielan−Jaworowska, 1970 is the most common mammalian taxon in the Upper Cretaceous (?lower Campanian) rocks of the Djadokhta Formation at
The extratarsal spur in extant monotremes consists of an os calcaris and a cornu calcaris. A poisonous extratarsal spur oc− curs only in the platypus (Ornithorhynchus); a possibly secondarily non−poisonous spur is present in echidnas... more
The extratarsal spur in extant monotremes consists of an os calcaris and a cornu calcaris. A poisonous extratarsal spur oc− curs only in the platypus (Ornithorhynchus); a possibly secondarily non−poisonous spur is present in echidnas (Tachy− glossus and Zaglossus). Some therian mammals (e.g., bats), reptiles (Chamaeleo), and amphibians have a spur−like struc− ture in the ankle, but this is not
Page 1. PHYLOGENY AND SYSTEMATICS OF MULTITUBERCULATE MAMMALS by ZOFIA KIELAN-JAWOROWSKA and JéRN H. HURUM ABSTRACT. We present a synopsis of high-rank multituberculate systematics and ...
The discovery of fragments of Asian Middle Jurassic mammals. from the Balabansai Formation (Middle Jurassic) of Kalmakerchin near the Kokart River in Kyrgyzstan is reported. The fragments consist of an upper molar with a worn crown and a... more
The discovery of fragments of Asian Middle Jurassic mammals. from the Balabansai Formation (Middle Jurassic) of Kalmakerchin near the Kokart River in Kyrgyzstan is reported. The fragments consist of an upper molar with a worn crown and a fragment of the proximal ulna. The molar, because of the presence of three roots and roughly rectangular shape, is tentatively assigned to the Docodonta. A mammalian incisor or reptilian tooth is also described. The red clays and sandstones of the Balabansai Formation, and their faunistic assemblage (plants, fish, ...
A Mongolian ankylosaurid specimen identified as Tarchia 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... more
A Mongolian ankylosaurid specimen identified as Tarchia 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 arrangement 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 specimens, including the morphology of the neural spines of the tail club handle and several of the largest osteoderms.
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ABSTRACT Latest Jurassic–earliest Cretaceous hydrocarbon seeps from Spitsbergen, Svalbard, are known to contain unusual fauna, lacking most of the species characteristic for roughly coeval seep deposits. This study summarizes and analyses... more
ABSTRACT Latest Jurassic–earliest Cretaceous hydrocarbon seeps from Spitsbergen, Svalbard, are known to contain unusual fauna, lacking most of the species characteristic for roughly coeval seep deposits. This study summarizes and analyses the fauna from 16 seep carbonate bodies from Spitsbergen to explain its composition. The seeps formed in a shallow epicontinental sea with widespread deposition of fine-grained, organic-rich sediments. They are spread over a relatively large area and are positioned roughly in the same interval, indicating seepage over extensive areas of the palaeo-Barents Sea. The seep fauna is very species rich and with low dominance, comprising 54 species, with a composition similar to that of Jurassic–Cretaceous normal-marine environments of other Boreal seas. Seep-restricted fauna is not abundant and is represented by four species only. Hokkaidoconchids and possible siboglinid worm tubes characteristic for high sulphide fluxes are rare. Apart from seep-restricted sulphide-mining lucinid and thyasirid bivalves, chemosymbiosis was also a source of nourishment for background solemyid and nucinellid bivalves, all of which take sulphide from infaunal sources. This all suggests a relatively weak sulphide flux. The high diversity and low dominance of the fauna and significant richness and abundance of background species is typical for shallow water seeps. □