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Bulogites multinodosus (Hauer, 1892) (Ammonoida, Triassic: Ceratitida) is revised in the context of a re-evaluation of the types of B. mojsvari (Arthaber, 1896), B. reiflingensis (Arthaber, 1896) and B. sondershusanus (Picard, 1892) together with a faunule mentioned by Spath (1934). We conclude herein that B. mojsvari and B. reiflingensis are synonyms of B. multinodosus. This relates also to B. pseudovindelicus (Arthaber, 1896) and B. reiflingensis var. exigua (Arthaber, 1896). B. sondershusanus is preliminarily kept as a separate species. [ABSTRACT FROM AUTHOR]

Deep-sea macrobenthic body fossils are scarce due to the lack of deep-sea sedimentary archives in onshore settings. Therefore, hypothesized migrations of shallow shelf taxa into the deep-sea after phases of mass extinction (onshore-offshore pattern in the literature) due to anoxic events is not constrained by the fossil record. To resolve this conundrum, we investigated 1,475 deep-sea sediment samples from the Atlantic, Pacific and Southern oceans (water depth ranging from 200 to 4,700 m), providing 41,460 spine fragments of the crown group Atelostomata (Holasteroida, Spatangoida). We show that the scarce fossil record of deep-sea echinoids is in fact a methodological artefact because it is limited by the almost exclusive use of onshore fossil archives. Our data advocate for a continuous record of deep-sea Atelostomata back to at least 104 Ma (late early Cretaceous), and literature records suggest even an older age (115 Ma). A gradual increase of different spine tip morphologies from the Albian to the Maastrichtian is observed. A subsequent, abrupt reduction in spine size and the loss of morphological inventory in the lowermost Paleogene is interpreted to be an expression of the "Lilliput Effect", related to nourishment depletion on the sea floor in the course of the Cretaceous-Paleogene (K-Pg) Boundary Event. The recovery from this event lasted at least 5 Ma, and post-K-Pg Boundary Event assemblages progress—without any further morphological breaks—towards the assemblages observed in modern deep-sea environments. Because atelostomate spine morphology is often species-specific, the variations in spine tip morphology trough time would indicate species changes taking place in the deep-sea. This observation is, therefore, interpreted to result from in-situ evolution in the deep-sea and not from onshore-offshore migrations. The calculation of the "atelostomate spine accumulation rate" (ASAR) reveals low values in pre-Campanian times, possibly related to high remineralization rates of organic matter in the water column in the course of the mid-Cretaceous Thermal Maximum and its aftermath. A Maastrichtian cooling pulse marks the irreversible onset of fluctuating but generally higher atelostomate biomass that continues throughout the Cenozoic. [ABSTRACT FROM AUTHOR]

Bithynian and Pelsonian (Anisian, Middle Triassic) Ammonoidea are generally rare in the Germanic Basin. Here, we describe ammonoids from the Jena and Rüdersdorf formations (Lower Muschelkalk) of Rüdersdorf (Brandenburg, Germany). This locality is peculiar in its isolated situation and its comparatively high diversity in ammonoids. This outcrop yielded several assemblages encompassing eight species: Balatonites ottonis (Buch, 1849), B. balatonicus (Mojsisovics, 1873), B. egregius (Arthaber, 1896), Beneckeia buchi (Alberti, 1834), Bulogites zoldianus (Mojsisovics, 1882), "Ceratites" antecedens (Beyrich, 1858), Discoptychites dux (Giebel, 1853) and Noetlingites strombecki (Griepenkerl, 1860). When the geographic distribution of these species are compared, it becomes evident that immigrants from the southeast and the southwest met in that region. Such immigrations were only possible during transgressions. Balatonites balatonicus, B. egregius and B. zoldianus are recorded from the area for the first time. Beneckeia is revised with a focus on Ben. buchi, one of the few true endemites of the Germanic Basin, using synchrotron data to describe its early ontogeny. The holotype of "Ceratites" antecedens is figured for the first time and a lectotype for Balatonites egregius is designated. [ABSTRACT FROM AUTHOR]

Spines of irregular echinoids occur in very high abundance in each specimen, and display distinct architecture as a result of the specialized functions of the spines; however, studies on spine microstructure in atelostomate echinoids have rarely been carried out. Accordingly, little is known about their specific morphology. This work aims to elaborate differences in the spine morphology of selected Atelostomata (Spatangoida and Holasteroida) in detail, and to discuss spine microstructure for its potential systematic value. Based on 82 atelostomate species (56 spatangoids and 26 holasteroids), we show that the perforation pattern in the internal cylinder of the spine (helicoidal versus horizontal pattern) provides a safe distinction between the Spatangoida and Holasteroida. According to this character we discuss the geological history of atelostomate echinoids, in particular their migration into the deep sea, based on well-preserved records of fossil spines. © 2015 The Linnean Society of London [ABSTRACT FROM AUTHOR]

Sulfide-rich environments in shallow water were considered as sites where animals acquired preadaptations enabling them to colonize deep-sea hydrothermal vents and seeps or where they survived extinction events in their deep-sea habitats. Here we document late Cenomanian shallow-water seep communities from the Tropic Shale in the Western Interior Seaway, United States, as a possible refutation of these hypotheses. The late Cenomanian was a time of extremely warm deep-water temperatures, which supposedly facilitated adaptations to the deep sea, and of widespread oceanic anoxia (oceanic anoxic event 2) that supposedly extinguished deep-water vent and seep faunas. Contrary to the expectations, the taxa of the Tropic Shale seeps were not found at coeval or younger deep-water seep or vent deposits. Furthermore, a cluster analysis of faunal similarity among Cretaceous vent and seep faunas revealed no distinction between pre- and post-Cenomanian seep faunas, but instead strong similarities among Aptian to Late Cretaceous seep faunas. This suggests that a low temperature gradient from shallow to deep water did not facilitate invasions of deep-sea vents and seeps from shallow water and that preadaptation for living at deep-sea vents and seeps did not evolve at shallow-water methane seeps. The vast majority of adaptations to successfully colonize deepsea vents and seeps were most likely acquired below the photic zone. [ABSTRACT FROM AUTHOR]

Abstract: The “An der Schanz quarry” near Burgberg exhibits parts of the Helvetic Seewen Formation. Its base is dated as Cenomanian, its top as Late Santonian by planktonic foraminifera by previous authors. A re-sampling of the section for inoceramid and δ13C stratigraphy gave an Early Coniacian age for the uppermost parts of the Seewen Formation. A literature review suggests that the top of Seewen Formation of the Allgäu (Bavaria) and Vorarlberg (Austria) is never younger than the Middle or terminal Middle Coniacian. δ13C data confirm the biostratigraphic dating by inoceramids. Furthermore, although only 28m thick, the section exhibits all important δ13C events for interbasinal correlation previously recognized in sections of England and northwestern Germany. The δ13C calibration of the LO of H. helvetica is shown to be diachronous and not of value for isochronous zonations. The Caburn δ13C event is suggested as a marker for the Middle-Upper Turonian boundary due to the concomitant FO of I. perplexus. The re-dating of the facies turnover from a calcareous biosedimentary system towards a marl dominated system (succeeding Amden Formation) is briefly compared with the situation observed in northwestern Germany, where comparable trends are mapable. [Copyright &y& Elsevier]

We reviewed the global stratigraphic and palaeobiogeographic distribution of Mytiloides incertus (Jimbo, 1894) in the context of a newly proposed standard inoceramid zonation for the central European upper Turonian (perplexus, striatoconcentricus, labiatoidiformis, scupini, waltersdorfensis waltersdorfensis interval zones). Where available, δ13C curves aided an interbasinal correlation. M. incertus enters first in the striatoconcentricus IZ. Last well-dated occurrences are from the lower scupini IZ. An acme of the species in the terminal labiatoidiformis IZ appears to be isochronous in Europe and the Western Interior of the United States. The occurrence of M. incertus together with other central European species (I. perplexus, M. striatoconcentricus) marks the end of an inoceramid endemic phase in the Western Interior. [ABSTRACT FROM AUTHOR]