Results 11 to 20 of about 2,224 (181)
Reproductive biology and anatomy of ammonites [PDF]
Scientific ReportsAmmonoid anatomy is still poorly known and every new record of a specimen with soft tissue-preservation yields valuable information. In view of the impressive morphological disparity of ammonoids, we can also expect some disparity in soft tissue anatomy.
Christian Klug +6 more
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Postmortem transport in fossil and modern shelled cephalopods [PDF]
PeerJ, 2018 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
doaj +3 more sources
NEW EARLY BATHONIAN BIGOTITINAE AND ZIGZAGICERATINAE (AMMONOIDEA, MIDDLE JURASSIC)
Rivista Italiana di Paleontologia e Stratigrafia, 2007 Several tens of Lower Bathonian Bigotites from Digne-Castellane region (SE France) and Cabo Mondego area (Portugal) have been reviewed. Three species have been distinguished in the lowermost subzone of the Zigzag Zone (Parvum Subzone) just above the ...
SIXTO R. FERNÁNDEZ-LÓPEZ +3 more
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VILLANIA'NIN (AMMONOIDEA) TÜRKİYE'DEKİ VARLIĞI HAKKINDA
Bulletin of the Mineral Research and Exploration, 1982 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
doaj +1 more source
About the stratigraphic position of the Lower Aptian Roloboceras hambrovi (Ammonoidea) level
Carnets de Géologie, 2008 In the stratotype of the Lower Aptian substage the position of the assemblage that includes Roloboceras spp. and Megatyloceras spp. has been clearly established as being in the middle part of the upper Bedoulian. Some authors have erected this horizon as
Conte Gabriel +3 more
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3D-Analysis of a non-planispiral ammonoid from the Hunsrück Slate: natural or pathological variation? [PDF]
PeerJ, 2017 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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Extreme abundance of ammonoids in mass accumulations from the Late Devonian of the Moroccan Anti-Atlas [PDF]
Acta Palaeontologica Polonica, 2022 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]
Acta Palaeontologica Polonica, 2022 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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Papers in Palaeontology, Volume 7, Issue 3, Page 1435-1457, August 2021., 2021 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
Biological Reviews, Volume 96, Issue 2, Page 576-610, April 2021., 2021 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
wiley +1 more source