Results 21 to 30 of about 814 (192)
TAXONOMY,STRATIGRAPHY AND PHYLOGENY OF THE NEW GENUS LANCEOPTYCHITES (AMMONOIDEA, ANISIAN)
For the first time a population analysis of compressed Ptychitidae (Ammonoidea) bed-by-bed collected from Prezzo Limestone (Upper Anisian, Southern Alps) is performed.
MARCO BALINI
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Postmortem transport in fossil and modern shelled cephalopods [PDF]
The chambered shells of cephalopod mollusks, such as modern Nautilus and fossil ammonoids, have the potential to float after death, which could result in significant postmortem transport of shells away from living habitats. Such transport would call into
Margaret M. Yacobucci
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3D-Analysis of a non-planispiral ammonoid from the Hunsrück Slate: natural or pathological variation? [PDF]
We herein examine the only known non-planispirally coiled early Devonian ammonoid, the holotype specimen of Ivoites opitzi, to investigate if the host was encrusted in vivo and if these sclerobionts were responsible for the trochospiral coiling observed ...
Julia Stilkerich +2 more
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VILLANIA'NIN (AMMONOIDEA) TÜRKİYE'DEKİ VARLIĞI HAKKINDA
Türkiye'deki varlığı ilk kez saptanan Villania bugüne değin Macaristan'a özgü bilinen bir ammonit cinsidir. Bilecik yöresinde bulunan iki örnek, Villania cf.
Füsun ALKAYA
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Extreme abundance of ammonoids in mass accumulations from the Late Devonian of the Moroccan Anti-Atlas [PDF]
The eastern Anti-Atlas is renowned for its highly fossiliferous outcrops of Devonian rocks. Ammonoids occur in rock-forming numbers at many localities in the Tafilalt and Maïder.
MERLE GREIF +2 more
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Dimorphism in tetragonitid ammonoid Tetragonites minimus from the Upper Cretaceous in Hokkaido, Northern Japan [PDF]
Mature modifications, ontogeny, and dimorphism of the small-sized tetragonitid ammonoid Tetragonites minimus were investigated in 43 specimens from the Santonian, Upper Cretaceous of the northwestern area of Hokkaido, Japan.
DAISUKE AIBA
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Abstract The ammonoid genus Arctoceras (Hyatt) occurs across all palaeolatitudes, and is a key genus for middle Smithian biostratigraphical correlations globally. In this study, intraspecific variations in conch morphology, ornamentation and allometry are examined in relation to stratigraphic position.
Bitten B. Hansen +4 more
wiley +1 more source
Recent advances in heteromorph ammonoid palaeobiology
ABSTRACT Heteromorphs are ammonoids forming a conch with detached whorls (open coiling) or non‐planispiral coiling. Such aberrant forms appeared convergently four times within this extinct group of cephalopods. Since Wiedmann's seminal paper in this journal, the palaeobiology of heteromorphs has advanced substantially.
René Hoffmann +9 more
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Early Cretaceous ammonites and dinoflagellates from the Western Tatra Mountains, Poland [PDF]
The first Early Cretaceous (Valanginian–Hauterivian) ammonite fauna from the lower part of the Kościeliska Marl Formation (Wściekły Żleb Member) of the Lower Sub-Tatric (Krížna) Nappe, in the Lejowa Valley of the Tatra Mountains are described.
Zdeněk Vašíček +6 more
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Fossils of Devonian ammonoids are abundant and well-preserved in the Anti-Atlas of Morocco; as such they provide an invaluable record of regional morphological disparity changes (diversity of shapes) that characterise the first steps of ammonoid ...
NINON ALLAIRE +6 more
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