0000000000117989

AUTHOR

John W.m. Jagt

Turonian marine amniotes from the Opole area in southwest Poland

A few isolated plesiosaurian and mosasauroid squamate teeth were collected from the Opole area in southwest Poland during the late nineteenth century. Calcareous nannofossil analysis of their associated rock matrix indicates an early Turonian age (nannofossil zone UC7; Mytiloides ex gr. labiatus and Inoceramus apicalis inoceramid zones), which is significant because this constitutes a globally enigmatic interval of marine amniote evolution. The Opole plesiosaurian teeth are attributable to polycotylids, but an indeterminate mesopodial was also recovered. They are similar to specimens from the Cenomanian-Turonian in the Saxonian Cretaceous Basin of Germany and the Chalk succession of England…

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Ammonite extinction and nautilid survival at the end of the Cretaceous

One of the puzzles about the end-Cretaceous extinctions is why some organisms disappeared and others survived. A notable example is the differential extinction of ammonites and survival of nautilids, the two groups of co-occurring, externally shelled cephalopods at the end of the Cretaceous. To investigate the role of geographic distribution in explaining this outcome, we compiled a database of all the occurrences of ammonites and the nautilid genus Eutrephoceras in the last 0.5 m.y. of the Maastrichtian. We also included recently published data on ammonite genera that appear to have briefly survived into the Paleocene. Using two metrics to evaluate the geographic range of each genus (first…

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The Gemmellaro Collection: first record of an anomuran from the Tithonian of Sicily, Italy

A recent field trip to Sicily and an examination of decapod crustacean collections at the Museo Geologico G.G. Gemmellaro in the centre of Palermo, Sicily (Italy), has demonstrated that most of the anomuran and brachyuran material described by Gemmellaro (Gemmellaro GG. 1869. Studi paleontologici sulla fauna del Calcare àTerebratula janitordel nord di Sicilia. Palermo: Lao, vol. 1, pp. 11–18) from the Tithonian of that island is still present. Interestingly, a single specimen in this lot was never mentioned, described or illustrated by that author. The species to which this particular individual is here shown to belong,Gastrosacus tuberosus, was first described and named 26 years later, in …

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Notes on selected Cretaceous echinoids from south-central Sakhalin, Far East Russia

AbstractFrom Albian, Santonian and Campanian strata in south-central Sakhalin, four echinoid taxa are described, illustrated and discussed. In Far East Russia, echinoids are rare constituents amongst mid- and Late Cretaceous macrofaunal assemblages in which inoceramid and non-inoceramid bivalves, plus heteromorph and non-heteromorph ammonites predominate. The sole regular species in the present lot is represented by an incomplete external mould of a primary spine of a rhabdocidarid,Polycidaris(?) sp., from the lower Campanian. Irregular taxa include a fragmentary, specifically indeterminate ‘pygurid’,Echinopygus(?) sp., of late Albian age, as well as two spatangoids. One of these, a toxaste…

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Distribution of late Maastrichtian pachydiscid and scaphitid ammonites in the Maastricht and Kunrade formations of the southeast Netherlands

Abstract The pachydiscid Pachydiscus ( Pachydiscus ) gollevillensis (d'Orbigny, 1850), long held to be confined to the ‘Kunrade Limestone’ (nowadays Kunrade Formation) in the eastern part of southern Limburg (Kunrade–Benzenrade area, the Netherlands), is now recorded from the basal Nekum Member (Maastricht Formation) at the ENCI-HeidelbergCement Group quarry, Sint-Pietersberg (Maastricht). Here we review the stratigraphic distribution of pachydiscid and scaphitid ammonites in outcrops west of the River Maas (Maastricht Formation) and in the Kunrade–Benzenrade area (Kunrade Formation). The latter unit has been correlated with part of the Lanaye Member (Gulpen Formation) up to the basal Emael…

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Ernst Julius Öpik’s (1916) note on the theory of explosion cratering onthe Moon’s surface—The complex case of a long-overlooked benchmark paper

High-velocity impact as a common phenomenon in planetary evolution was ignored until well into the twentieth century, mostly because of inadequate understanding of cratering processes. An eight-page note, published in Russian by the young Ernst Julius Opik, a great Estonian astronomer, was among the key selenological papers, but due to the language barrier, it was barely known and mostly incorrectly cited. This particular paper is here intended to serve as an explanatory supplement to an English translation of Opik's article, but also to document an early stage in our understanding of cratering. First, we outline the historical–biographical background of this benchmark paper, and second, a …

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Ammonite faunas from condensed Cenomanian-Turonian sections (‘Tourtias’) in southern Belgium and northern France

AbstractIn southern Belgium (Mons Basin and Tournai region) and northern France (area between Lille, Valenciennes and Maubeuge), condensed sequences have been referred to as ‘tourtias’ since the start of the nineteenth century. These levels correspond to a succession of trangressive systems tracts and generally appear as dark green, glauconitic and microconglomeratic facies. They are distributed all along the base of the more important transgressive systems tracts of the Cenomanian and basal Turonian from the Boulonnais (northwest France) to the Mons Basin (southern Belgium), through the Artois and Douaisis. Their age can now be determined more accurately by identification of their ammonite…

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Ammonites on the Brink of Extinction: Diversity, Abundance, and Ecology of the Order Ammonoidea at the Cretaceous/Paleogene (K/Pg) Boundary

We examined the stratigraphic distribution of ammonites at a total of 29 sites around the world in the last 0.5 myr of the Maastrichtian. We demarcated this interval using biostratigraphy, magnetostratigraphy, cyclostratigraphy, and data on fossil occurrences in relation to the K/Pg boundary in sections without any facies change between the highest ammonites and the K/Pg boundary. The ammonites at this time represent all four Mesozoic suborders comprising six superfamilies, 31 (sub)genera, and 57 species. The distribution of ammonites is dependent on the environmental setting. Recent data suggest that ammonites persisted to the boundary and some species may have survived for several tens of…

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Advances in Cretaceous palaeontology and stratigraphy – Christopher John Wood Memorial Volume; editors' preface

Abstract In the last week of January 2016, the ‘Cretaceous community’ lost another of their prominent members, Chris Wood. During recent decades, Chris had been active in the United Kingdom as well as in mainland Europe, particularly in Germany and Poland. Several years ago he had been forced to leave the ranks of Associate Editors with Cretaceous Research , due to a severe illness that he was adamant to overcome. Later in 2016, two of us, fellow editors with that journal for a number of years, with the help of Rory Mortimore, approached former colleagues and friends of Chris's to contribute to a special issue. From the start, the idea has been to cover all aspects of Cretaceous stratigraph…

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First record of the enigmatic coleoid genus Longibelus from Sakhalin (Far East Russia): a contribution to our understanding of Cretaceous coleoid habitats in the Pacific Realm

AbstractA newly collected specimen of the enigmatic coleoid genus Longibelus is recorded from lower Turonian strata along the River Shadrinka in Sakhalin (Russian Far East). To date, this is the first record of Late Cretaceous coleoid cephalopods from the island and, in fact, from the entire Pacific coast of the Russian Federation. Lithological characteristics, coupled with published geochemical analyses (δ13C and Corg content), suggest the habitat of this coleoid taxon to have been the middle to outer (i.e. distal) shelf. Its provenance from the stratigraphical level that is known as the Scaphites Event, characterised by a mass occurrence of Scaphites and Yesoites, may be indicative of occ…

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A Dutch contribution to early interpretations of Meteor Crater, Arizona, USA – Marten Edsge Mulder’s ignored 1911 paper

Abstract Following the first scientific descriptions in the late nineteenth century, the origin of the curious structure currently known as Meteor Crater (or Barringer Crater) in Arizona (USA) remained controversial until well into the twentieth century. Within the context of commercial mining, Daniel Moreau Barringer’s view that it recorded a substratum-penetrative meteorite impact (with the cosmic body still preserved) was commonly discarded. Marten Edsge Mulder (1847–1928), Dutch professor of medicine, found fault with Barringer’s non-explosive model. In 1911, Mulder advanced, in an ignored paper written in Dutch, a novel model of an explosive meteorite (‘meteor’ in Mulder’s terminology)…

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Comment on the letter of the Society of Vertebrate Paleontology (SVP) dated April 21, 2020 regarding “Fossils from conflict zones and reproducibility of fossil-based scientific data”: the importance of private collections

International audience

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An unusual conchorhynch from the upper Maastrichtian of the southeast Netherlands and the distinction between nautiloid and ammonoid conchorhynchs (Mollusca, Cephalopoda)

Abstract A single, atypical conchorhynch (calcitic tip of a cephalopod lower jaw), recovered from the uppermost Meerssen Member (Maastricht Formation, upper Maastrichtian) at the former ENCI-HeidelbergCement Group quarry, south of Maastricht, is described as a new parataxon, Conchorhynchus illustris sp. nov. The specimen can be differentiated from all previous conchorhynch records on account of its large size, elongated shape and, in particular, of the structure of its apical part which is smooth and forwardly elongated. During the Late Cretaceous, conchorhynchs formed part of the jaw apparatus of nautilids and of two ammonoid suborders, Phylloceratina and Lytoceratina. Since conchorhynchs …

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Ammonite dating of latest Cretaceous mosasaurid reptiles (Squamata, Mosasauroidea) from Jordan—preliminary observations

Newly collected ammonoid material from the uppermost Cretaceous portion of the Muwaqqar Chalk Marl Formation exposed some 30 km southeast of the Qasr Al’Harrana area (east-central Jordan) includes medium-sized baculitids (Baculites ovatus auctorum, non Say), the sphenodiscid Libycoceras acutodorsatus (Noetling) and the pachydiscids Menuites fresvillensis (Seunes) and Pachydiscus (Pachydiscus) dossantosi (Maury). Of the two last named taxa, the former is a good marker species for the upper Maastrichtian, with records from Europe, central Chile, South India, Baluchistan (Pakistan), Australia, Madagascar and South Africa. The latter is known from the United Arab Emirates/Oman border area, from…

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Stratigraphical ranges of tegulated inoceramid bivalves in the type area of the Maastrichtian Stage (Belgium, the Netherlands)

Abstract Recently collected material, in fine- to medium-grained biocalcarenites and in coeval flint nodules, of the tegulated inoceramid taxa Spyridoceramus tegulatus (von Hagenow, 1842) and Tenuipteria argentea (Conrad, 1858) from various members of the Gulpen Formation and the overlying Maastricht Formation allows their stratigraphical ranges to be refined. It is concluded that the ranges correspond closely to those in east-central Poland (Vistula [Wisla] River valley region), where S. tegulatus occurs in the lower Maastrichtian and lower upper Maastrichtian ( Endocostea typica , Trochoceramus radiosus and ‘ Inoceramus ’ ianjonaensis inoceramid zones, or Belemnella occidentalis and Belem…

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