Subjects -> EARTH SCIENCES (Total: 771 journals)
    - EARTH SCIENCES (527 journals)
    - GEOLOGY (94 journals)
    - GEOPHYSICS (33 journals)
    - HYDROLOGY (29 journals)
    - OCEANOGRAPHY (88 journals)

EARTH SCIENCES (527 journals)            First | 1 2 3     

Showing 401 - 371 of 371 Journals sorted alphabetically
Physical Geography     Hybrid Journal   (Followers: 8)
Physical Science International Journal     Open Access  
Physics in Medicine & Biology     Full-text available via subscription   (Followers: 15)
Physics of Life Reviews     Hybrid Journal   (Followers: 1)
Physics of Metals and Metallography     Hybrid Journal   (Followers: 18)
Physics of Plasmas     Hybrid Journal   (Followers: 10)
Physics of the Earth and Planetary Interiors     Hybrid Journal   (Followers: 34)
Physics of the Solid State     Hybrid Journal   (Followers: 4)
Physics of Wave Phenomena     Hybrid Journal  
Physics World     Full-text available via subscription   (Followers: 18)
Physik in unserer Zeit     Hybrid Journal   (Followers: 9)
Pirineos     Open Access  
Planet     Open Access   (Followers: 4)
Plasma Physics and Controlled Fusion     Hybrid Journal   (Followers: 6)
Plasma Physics Reports     Hybrid Journal   (Followers: 7)
Polar Record     Hybrid Journal   (Followers: 2)
Positioning     Open Access   (Followers: 4)
Pramana     Open Access   (Followers: 13)
Precambrian Research     Hybrid Journal   (Followers: 7)
Preview     Hybrid Journal  
Proceedings of the Geologists' Association     Full-text available via subscription   (Followers: 6)
Proceedings of the Linnean Society of New South Wales     Full-text available via subscription   (Followers: 2)
Proceedings of the Yorkshire Geological Society     Hybrid Journal   (Followers: 1)
Progress in Earth and Planetary Science     Open Access   (Followers: 15)
Pure and Applied Geophysics     Hybrid Journal   (Followers: 12)
Quarterly Journal of Engineering Geology and Hydrogeology     Hybrid Journal   (Followers: 4)
Quaternary     Open Access  
Quaternary Australasia     Full-text available via subscription  
Quaternary Geochronology     Hybrid Journal   (Followers: 8)
Quaternary International     Hybrid Journal   (Followers: 14)
Quaternary Research     Full-text available via subscription   (Followers: 19)
Quaternary Science Advances     Open Access  
Quaternary Science Reviews     Hybrid Journal   (Followers: 26)
Radiocarbon     Hybrid Journal   (Followers: 12)
Remote Sensing     Open Access   (Followers: 57)
Remote Sensing Applications : Society and Environment     Full-text available via subscription   (Followers: 9)
Remote Sensing in Earth Systems Sciences     Hybrid Journal   (Followers: 5)
Remote Sensing Letters     Hybrid Journal   (Followers: 45)
Remote Sensing Science     Open Access   (Followers: 29)
Rendiconti Lincei     Hybrid Journal  
Reports on Geodesy and Geoinformatics     Open Access   (Followers: 8)
Reports on Mathematical Physics     Full-text available via subscription   (Followers: 2)
Research & Reviews : Journal of Space Science & Technology     Full-text available via subscription   (Followers: 18)
Resource Geology     Hybrid Journal   (Followers: 6)
Resources, Environment and Sustainability     Open Access   (Followers: 1)
Results in Geochemistry     Open Access  
Results in Geophysical Sciences     Open Access  
Reviews in Mineralogy and Geochemistry     Hybrid Journal   (Followers: 4)
Reviews of Modern Physics     Full-text available via subscription   (Followers: 31)
Revista Cerrados     Open Access  
Revista de Ciências Exatas Aplicadas e Tecnológicas da Universidade de Passo Fundo : CIATEC-UPF     Open Access  
Revista de Ingenieria Sismica     Open Access  
Revista de Investigaciones en Energía, Medio Ambiente y Tecnología     Open Access  
Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales     Open Access  
Revista de Teledetección     Open Access  
Revista Geológica de Chile     Open Access  
Revue Française de Géotechnique     Hybrid Journal  
Rock Mechanics and Rock Engineering     Hybrid Journal   (Followers: 7)
Rocks & Minerals     Hybrid Journal   (Followers: 3)
Russian Geology and Geophysics     Hybrid Journal   (Followers: 2)
Russian Journal of Mathematical Physics     Full-text available via subscription  
Russian Journal of Pacific Geology     Hybrid Journal  
Russian Physics Journal     Hybrid Journal   (Followers: 1)
Science China Earth Sciences     Hybrid Journal   (Followers: 3)
Science News     Hybrid Journal   (Followers: 11)
Science of Remote Sensing     Open Access   (Followers: 7)
Scientific Annals of Stefan cel Mare University of Suceava. Geography Series     Open Access  
Scientific Journal of Earth Science     Open Access   (Followers: 1)
Scientific Reports     Open Access   (Followers: 85)
Sedimentary Geology     Hybrid Journal   (Followers: 20)
Sedimentology     Hybrid Journal   (Followers: 15)
Seismic Instruments     Hybrid Journal   (Followers: 1)
Seismological Research Letters     Full-text available via subscription   (Followers: 12)
Soil Dynamics and Earthquake Engineering     Hybrid Journal   (Followers: 14)
Soil Security     Open Access   (Followers: 3)
Solid Earth     Open Access   (Followers: 5)
Solid Earth Discussions     Open Access   (Followers: 1)
Solid Earth Sciences     Open Access   (Followers: 1)
South African Journal of Geomatics     Open Access   (Followers: 2)
Standort - Zeitschrift für angewandte Geographie     Hybrid Journal   (Followers: 2)
Stratigraphy and Geological Correlation     Full-text available via subscription   (Followers: 2)
Studia Geophysica et Geodaetica     Hybrid Journal   (Followers: 1)
Studia Geotechnica et Mechanica     Open Access  
Studia Universitatis Babes-Bolyai, Geologia     Open Access  
Survey Review     Hybrid Journal   (Followers: 6)
Surveys in Geophysics     Hybrid Journal   (Followers: 3)
Swiss Journal of Palaeontology     Hybrid Journal   (Followers: 4)
Tectonics     Full-text available via subscription   (Followers: 15)
Tectonophysics     Hybrid Journal   (Followers: 24)
Tellus A     Open Access   (Followers: 21)
Tellus B     Open Access   (Followers: 20)
Terra Latinoamericana     Open Access  
Terra Nova     Hybrid Journal   (Followers: 5)
The Compass : Earth Science Journal of Sigma Gamma Epsilon     Open Access  
The Holocene     Hybrid Journal   (Followers: 16)
The Leading Edge     Hybrid Journal   (Followers: 1)
Transportation Infrastructure Geotechnology     Hybrid Journal   (Followers: 8)
Turkish Journal of Earth Sciences     Open Access  
UD y la Geomática     Open Access  
Unconventional Resources     Open Access  
Underwater Technology: The International Journal of the Society for Underwater     Full-text available via subscription   (Followers: 1)
Universal Journal of Geoscience     Open Access  
Unoesc & Ciência - ACET     Open Access  
Vadose Zone Journal     Open Access   (Followers: 5)
Volcanica     Open Access  
Water     Open Access   (Followers: 10)
Water International     Hybrid Journal   (Followers: 19)
Water Resources     Hybrid Journal   (Followers: 21)
Water Resources Research     Full-text available via subscription   (Followers: 94)
Watershed Ecology and the Environment     Open Access  
Weather, Climate, and Society     Hybrid Journal   (Followers: 15)
Wiley Interdisciplinary Reviews - Climate Change     Hybrid Journal   (Followers: 33)
World Environment     Open Access   (Followers: 1)
Yearbook of the Association of Pacific Coast Geographers     Full-text available via subscription   (Followers: 2)
Yugra State University Bulletin     Open Access   (Followers: 1)
Zeitschrift der Deutschen Gesellschaft für Geowissenschaften     Full-text available via subscription   (Followers: 3)
Zeitschrift für Geomorphologie     Full-text available via subscription   (Followers: 5)
Zitteliana     Open Access  
Землеустрій, кадастр і моніторинг земель     Open Access   (Followers: 1)

  First | 1 2 3     

Similar Journals
Journal Cover
Swiss Journal of Palaeontology
Journal Prestige (SJR): 0.396
Citation Impact (citeScore): 1
Number of Followers: 4  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1664-2376 - ISSN (Online) 1664-2384
Published by Springer-Verlag Homepage  [2469 journals]
  • The first Jurassic coelacanth from Switzerland

    • Free pre-print version: Loading...

      Abstract: Abstract Coelacanths form a clade of sarcopterygian fish represented today by a single genus, Latimeria. The fossil record of the group, which dates back to the Early Devonian, is sparse. In Switzerland, only Triassic sites in the east and southeast of the country have yielded fossils of coelacanths. Here, we describe and study the very first coelacanth of the Jurassic period (Toarcian stage) from Switzerland. The unique specimen, represented by a sub-complete individual, possesses morphological characteristics allowing assignment to the genus Libys (e.g., sensory canals opening through a large groove crossed by pillars), a marine coelacanth previously known only in the Late Jurassic of Germany. Morphological characters are different enough from the type species, Libys polypterus, to erect a new species of Libys named Libys callolepis sp. nov. The presence of Libys callolepis sp. nov. in Lower Jurassic beds extends the stratigraphic range of the genus Libys by about 34 million years, but without increasing considerably its geographic distribution. Belonging to the modern family Latimeriidae, the occurrence of Libys callolepis sp. nov. heralds a long period, up to the present day, of coelacanth genera with very long stratigraphic range and reduced morphological disparity, which have earned them the nickname of ‘living fossils’.
      PubDate: 2022-09-22
       
  • Integrated palynology and sedimentology of the Mississippian of the
           Tisdafine Basin (Eastern Anti-Atlas, Morocco)

    • Free pre-print version: Loading...

      Abstract: Abstract The Mississippian (Tournaisian–Visean) of the Jbel Asdaf area in the Tisdafine Basin (Eastern Anti-Atlas, Morocco) has been, for the first time, the subject of a palynological study. This work aims first to describe the lithological and the paleontological composition of the Aït Yalla and Tinerhir Formations, then to refine the age, reconstruct the paleoenvironment and assess the thermal maturity of the organic matter. The studied section is subdivided, from oldest to youngest, into three intervals, according to their lithological and paleontological compositions. Lithologically, the lower interval (lower part of the Aït Yalla Formation) and middle interval (upper part of the Aït Yalla Formation and basal part of the Tinerhir Formation) consist mostly of clay shales and green shales, respectively, both alternating with limestone or sandstone beds. The upper interval (upper part of the Tinerhir Formation) is dominated by sandstones, also alternating with pelitic-sandstone or limestone beds. The kerogen delivered by the analyzed samples is mostly of continental origin, composed mainly of opaque phytoclasts, while translucent phytoclasts and miospores are less represented. Marine fraction, consisting mainly of granular amorphous organic matter and some phytoplankton, are rare. Biostratigraphically, the late Visean Tripartites vetustus–Rotaspora fracta (VF) miospore Zone of the Western Europe biozonal scheme is recognized with some regards in the Tinerhir Formation, based on the first occurrence of the miospore Rotaspora cf. knoxi. Vallatisporites aff. ciliaris is another biostratigraphic marker taxon of the assemblage, whose the last occurrence marks the end of the VF Biozone at the top of the analyzed section. Qualitative and quantitative parameters of the different palynofacies constituents (e.g., shape, size, % of opaque and translucent phytoclasts) show, from the base to the top of the section, a gradual transition from a distal marine environment generally recognized in the Aït Yalla Formation towards an intermediate marine environment in the Tinerhir Formation, suggesting a sea-level fall. Optical analyses performed on the color of palynomorphs, mainly spores, suggest a thermal maturity, ranging from late mature to early post-mature stage for most of the analysed samples, with a burial depth and a temperature of at least 3300 m and 90 °C, respectively.
      PubDate: 2022-08-24
       
  • A study on benthic molluscs and stable isotopes from Kutch, western India
           reveals early Eocene hyperthermals and pronounced transgression during
           ETM2 and H2 events

    • Free pre-print version: Loading...

      Abstract: Abstract The early Eocene greenhouse Earth experienced several transient global warming events, indicated by sharp negative excursions in the stable isotope ratios of carbon and oxygen. A huge amount of CO2, enriched with 12C, was released in the ocean–atmosphere system leading to warming. The Paleocene–Eocene boundary is demarcated by the most significant and well-known hyperthermal event, Paleocene–Eocene thermal maximum (PETM). The PETM is documented to be accompanied by a transgression. The later hyperthermals are relatively less studied. Information on the hyperthermals from the palaeo-tropical basins are relatively few. Here, we present a high-resolution litho-, bio- and isotope–stratigraphic analysis of the early Eocene succession from the Kutch Basin, western India. Stable isotopes of carbon and oxygen were analysed from sediments (δ13Corg) and mollusc shells (δ13Ccarb and δ18Ocarb). The succession, prevailingly with lignite, along with carbonaceous black shale and plenty of fossil plant remains, is primarily a product of terrestrial environment. A pronounced marine transgression, characterised by marine mollusc bearing glauconitic shale in the middle of the succession, indicates a coastal transitional setting between the ocean and land. The δ13C curve of organic carbon reveals five negative excursions, which are identified as the PETM, Eocene thermal maximum 2 (ETM2)/H1, H2, I1 and I2 in ascending order. The hyperthermal pair of ETM2–H2 corresponds with the marine interval. δ13Ccarb and δ18Ocarb from the middle part of the succession reveal concomitant negative excursions. The association between these hyperthermals and transgression appears to be regionally and globally valid, which strongly suggests a causal link between them.
      PubDate: 2022-07-26
       
  • A new pachypleurosaur from the Early Ladinian Prosanto Formation in the
           Eastern Alps of Switzerland

    • Free pre-print version: Loading...

      Abstract: Abstract The Alpine Prosanto Formation (Middle Triassic) cropping out in the Ducan region in eastern Switzerland has yielded a rich fish and reptile fauna. Here, we present new pachypleurosaur remains from the upper part of the formation (Early Ladinian), similar to the previously known pachypleurosaurs from the Middle Triassic UNESCO World Heritage Site of Monte San Giorgio in southern Switzerland/northern Italy. From these remains, a new pachypleurosaur species, Prosantosaurus scheffoldi nov. gen. et spec., is described on the basis of six fairly complete skeletons, one disarticulated specimen and an isolated skull. As is typical for pachypleurosaurs and most other Triassic marine reptiles, the new taxon is based to a large degree on a combination of characters (e.g., nasals articulating broadly with the anterior margins of the prefrontals and lacking posterior processes; postorbitals with rounded anterior processes that articulate with the postfrontals anterolaterally) rather than on many unambiguous autapomorphies, although a few of the latter were found including (1) a premaxilla which is excluded from entering both the external and internal nares and (2) a parietal, which is distinctly longer than wide and carrying distinct anterolaterally angled processes. Phylogenetic relationships of the new taxon are tested within European Pachypleurosauria, revealing that the new species is the sister taxon to a clade including Serpianosaurus, Proneusticosaurus, and the monophyletic Neusticosaurus spp. Mapping of palaeogeographic and stratigraphical distribution of valid European pachypleurosaurs shows that a formerly proposed scenario of migration of pachypleurosaurs from the eastern Palaeotethys during the Olenekian into the Germanic Basin and a subsequent diversification and invasion during the Anisian into the intraplatform basins of the South Alpine realm must be re-assessed. The exceptional preservation and preparation of the Ducan fossils further allow the description of tooth replacement patterns for the first time in a European pachypleurosaur species. The “alveolarization” of replacement teeth, the horizontal replacement pattern, and the subsequent remodelling of the functional alveoli during tooth replacement supports the monophyly of Sauropterygia as discussed before.
      PubDate: 2022-07-13
      DOI: 10.1186/s13358-022-00254-2
       
  • Damaged glyptodontid skulls from Late Pleistocene sites of northwestern
           Venezuela: evidence of hunting by humans'

    • Free pre-print version: Loading...

      Abstract: Abstract The Muaco and Taima-Taima sites, in Falcón State of northwestern Venezuela, are among the earliest sites of human occupation in South America containing artifacts associated with preserved megafaunal remains and dating between 19,810 and 15,780 calybp. Here we report novel visual and CT scanning analysis of six glyptodont skulls of Glyptotherium cf. cylindricum from these sites, of which four exhibit distinct and similar patterns of breakages in the fronto-parietal region that suggest intentional blows by direct percussion by humans, with fractures not being diagenetic but instead antemortem or transmortem. This hypothesized and unreported hunting technique focused in an area of the skull where the cephalic shield becomes thin, thus increasing the effectiveness of the blow. From Taima-Taima other glyptodont remains included an inverted carapace, also previously reported as probable evidence of human–glyptodont interaction during the latest Pleistocene. We estimated that roughly 150-170 Kg of potentially accessible muscles and fat of an adult Glyptotherium cylindricum could be used as food sources.
      PubDate: 2022-06-16
      DOI: 10.1186/s13358-022-00253-3
       
  • Phosphatized adductor muscle remains in a Cenomanian limid bivalve from
           Villers-sur-Mer (France)

    • Free pre-print version: Loading...

      Abstract: Abstract Soft-tissue preservation in molluscs is generally rare, particularly in bivalves and gastropods. Here, we report a three-dimensionally preserved specimen of the limid Acesta clypeiformis from the Cenomanian of France that shows preservation of organic structures of the adductor muscles. Examination under UV-light revealed likely phosphatisation of organic remains, which was corroborated by EDX-analyses. We suggest that the parts of the adductor muscles that are very close to the attachment are particularly resistant to decay and thus may be preserved even under taphonomic conditions usually not favouring soft-tissue fossilisation.
      PubDate: 2022-06-03
      DOI: 10.1186/s13358-022-00252-4
       
  • A new ichnotaxonomic name for burrows in vertebrate coprolites from the
           Miocene Chesapeake Group of Maryland, U.S.A

    • Free pre-print version: Loading...

      Abstract: Abstract A new ichnotaxonomic name, Transexcrementum cuniculus, is applied to tubular (cylindrical) tunnelings in coprolites. The type series of T. cuniculus consists of burrowed vertebrate (probably crocodilian) coprolites that originate from the Miocene Chesapeake Group of Maryland, U.S.A. These complex trace fossils exhibit the following combination of characters: burrows not lined nor backfilled; opening and transverse sections sub-circular; diameter supra-millimetric, up to ca. 20 mm, rather constant throughout; inner termination(s) rounded/conical; tunnel morphology straight or gently curved, sometimes branching; internal sculpturing sometimes present in form of short and irregularly oriented scratches and gouges. Clusters of the same kinds of gouges may also mark the outer surface of the coprolite. The tunneling tracemaker likely engaged in coprophagy; however, it is unclear what kind of organisms could have produced these burrows. Judging from the overall rarity of Transexcrementum cuniculus occurrences in the fossil record, the tracemaker responsible for the burrows might also have been rare, or fed on faeces only occasionally.
      PubDate: 2022-05-31
      DOI: 10.1186/s13358-022-00250-6
       
  • Revision of the genus Protadelomys, a middle Eocene theridomyoid rodent:
           evolutionary and biochronological implications

    • Free pre-print version: Loading...

      Abstract: Abstract The generic status of the species referred to Protadelomys has long been problematic. Most Protadelomys species are now considered paraphyletic, except for the type species P. cartieri and for P. lugdunensis. Here, we revised these two species from their type locality, Egerkingen (Swiss Jura) for P. cartieri and Lissieu (Rhône, France) for P. lugdunensis. For the latter species, we also consider the locality of Laprade (Tarn-et-Garonne, Quercy, France). Additionally, we revised the material attributed to Protadelomys species that is now considered paraphyletic: 'P. alsaticus from Bouxwiller (Bas-Rhin, France) and Cuzal (Lot, Quercy, France), 'P. maximini from St-Maximin (Gard, France), and 'P. nievesae from Casa Ramon (Huesca, Spain). Our detailed morphological analysis enables us to better characterize the extent of the morphological and size variability in all Protadelomys and 'Protadelomys species. We show that both P. cartieri and P. lugdunensis co-existed in Egerkingen, Lissieu, and Laprade. We also erected a new genus and species, Homœtreposciurus egerkingensis, and reported the presence of Eoelfomys from Egerkingen. Eoelfomys is here described as a new genus and species from Laprade. Size and morphological comparisons enabled us to detect large intraspecific variation in the material of 'P. alsaticus from Bouxwiller, as well as in the type population of 'P. maximini. The co-occurrence of the two Protadelomys species, at least in two localities, in addition to the revision of the features characterizing the three species of 'Protadelomys, led us to question the existence of a single evolutionary lineage (chronospecies), as previously recognized from 'P. maximini to P. lugdunensis.
      PubDate: 2022-05-30
      DOI: 10.1186/s13358-022-00245-3
       
  • Cephalopod palaeobiology: evolution and life history of the most
           intelligent invertebrates

    • Free pre-print version: Loading...

      Abstract: Abstract Sigurd von Boletzky was a cephalopod researcher who was world-renowned for his enthusiasm for his field of research, for his friendly and calm personality, and, of course, his publications. He dedicated most of his life as active researcher on the development, biology and evolution of coleoids. Nevertheless, he was always curious to learn about other cephalopods as well. Sigurd passed away in Switzerland on September 28th 2020. We dedicate this text and volume to his memory.
      PubDate: 2022-05-19
      DOI: 10.1186/s13358-022-00247-1
       
  • Morphological disparity in extant and extinct sepiid phragmocones:
           morphological adaptions for phragmocone strength compared to those related
           to cameral liquid emptying hypotheses

    • Free pre-print version: Loading...

      Abstract: Abstract The phragmocone-bearing coleoid cephalopods Sepia, Sepiella, Metasepia and Hemisepius (sepiids) are the most diverse of all extant chambered cephalopods and show the highest disparity. As such, they have a great potential to serve as model organisms to better understand the paleobiology not only of extinct coleoids, but of extinct nautiloids and ammonoids as well. Here, we present new measurements from the phragmocones of Sepia and Sepiella and relate these to known maximum depths. While these latter data remain few for some species, in aggregate they provide progress allowing this work. In so doing, we expand upon the great legacy of Sigurd von Boletzky. We show that deep water-inhabiting sepiids have phragmocones with a higher number of septa per length, a smaller area covered by the last chamber in relation to the volume of all previous phragmocone chambers, are smaller in size (length and volume), and bear dorsal shields that have strengthening central rib(s) compared to most species from shallower water; the very small endemic species of South Africa may be an exception. We show that the various subgenera defined by Khromov (1987) are not monophyletic clades but morphological groupings explicitly related to depth, partially evolved convergently. We conclude with analyses of Australian sepiid assemblages and show that these are depth related in ways analogous to ammonite and/or nautiloid assemblages of the past that are later commingled through post-mortal drift.
      PubDate: 2022-05-03
      DOI: 10.1186/s13358-022-00248-0
       
  • Relationships of growth increments of internal shells and age through
           entire life cycles in three cultured neritic cephalopods (Mollusca:
           Cephalopoda) with re-evaluation as application for age determination

    • Free pre-print version: Loading...

      Abstract: Abstract Relationships between growth increments of internal shell and age was studied in three neritic decapod cephalopods cultured in laboratory through their entire life cycles. The studied cephalopods were the nektic Sepioteuthis lessoniana d’Orbigny, 1826, Sepia pharaonis Ehrenberg, 1831 and Sepiella inermis Van Hasselt, 1835. Most of the relationship models are in cubic parabolic, except when numbers of increments were estimated from age in S. pharaonis. Differences of numbers of increments from the real age were higher in the pelagic S. lessoniana when compared to the benthic sepiids. The differences were higher in juvenile stages (< 60 days after hatching) than adult stages (> 60 days) in the three species. The increment rate is close to the “one day one increment” assumption. The differences of numbers of increments from the ages and the rate of increment apposition revealed the transition point of the life cycle from 60 days of age, corresponding to the sexual maturity or adult stages. Numbers of increments with higher accuracy are reevaluated to be reliable for age determination at least for the neritic species in the tropical zone, where environmental conditions are more stable, regarding the life styles and stages in life cycles of each species.
      PubDate: 2022-04-18
      DOI: 10.1186/s13358-022-00249-z
       
  • Is the relative thickness of ammonoid septa influenced by ocean
           acidification, phylogenetic relationships and palaeogeographic
           position'

    • Free pre-print version: Loading...

      Abstract: Abstract The impact of increasing atmospheric CO2 and the resulting decreasing pH of seawater are in the focus of current environmental research. These factors cause problems for marine calcifiers such as reduced calcification rates and the dissolution of calcareous skeletons. While the impact on recent organisms is well established, little is known about long-term evolutionary consequences. Here, we assessed whether ammonoids reacted to environmental change by changing septal thickness. We measured the septal thickness of ammonoid phragmocones through ontogeny in order to test the hypothesis that atmospheric pCO2, seawater pH and other factors affected aragonite biomineralisation in ammonoids. Particularly, we studied septal thickness of ammonoids before and after the ocean acidification event in the latest Triassic until the Early Cretaceous. Early Jurassic ammonoid lineages had thinner septa relative to diameter than their Late Triassic relatives, which we tentatively interpret as consequence of a positive selection for reduced shell material as an evolutionary response to this ocean acidification event. This response was preserved within several lineages among the Early Jurassic descendants of these ammonoids. By contrast, we did not find a significant correlation between septal thickness and long-term atmospheric pCO2 or seawater pH, but we discovered a correlation with palaeolatitude.
      PubDate: 2022-04-18
      DOI: 10.1186/s13358-022-00246-2
       
  • Scleractinian corals from the Lower Cretaceous of the Alpstein area
           (Anthozoa; Vitznau Marl; lower Valanginian) and a preliminary comparison
           with contemporaneous coral assemblages

    • Free pre-print version: Loading...

      Abstract: Abstract From the Vitznau Marl (lower Valanginian) at the locality Wart in northeastern Switzerland (Alpstein area), 18 species from 17 genera and 13 families are described, including the genera Actinaraea, Actinastrea, Adelocoenia, Aplosmilia, Axosmilia, Complexastrea, Cyathophora, Dermosmilia, Fungiastraea, Heterocoenia, Latiastrea, Montlivaltia, Placophyllia, Pleurophyllia, Stylophyllopsis, Thamnoseris, and specimens showing affinities to solitary stylophyllids. The corals from the Vitznau Marl were derived from a limestone–marl alternation that is fossiliferous and clay-rich at the base (Vitznau Marl), containing crinoids, bryozoans, and sparse reworked corals and sponges. The coral fauna is distinctly dominated by forms belonging to the category of lowest to no polyp integration (50%), followed by species of the cerioid-plocoid group (33%) and forms having the highest polyp integration (thamnasterioid; 17%). With regard to polypar size, the Wart fauna is dominated by corals having large-size (> 9 mm) polyps (= 39%), followed by corals having medium- (> 2.5‒9 mm; 33%) and small-size polyps (up to 2.5 mm; 28%). Based on morphological features, the fauna from the Vitznau Marl closely corresponds to coral assemblages that are subjected to near-chronic, moderate sediment-turbidity stress that is punctuated by high-stress events, and that are largely or entirely heterotrophic. No coral fabric was observed that would suggest a biohermal development. But in a very small number of places, structures are present which might be fragments of crusts of microbialites, pointing to the hypothesis that at least a few of the corals might have been a part of some kind of bioconstruction. At the species-level, the fauna of the Vitznau Marl shows either no or very little affinities to other Valanginian assemblages such as to the fauna of Hungary (4.3%), followed by the associations of Ukraine, Switzerland (non-Vitznau), Spain (SpII), and Bulgaria. At the genus-level, the Wart fauna shows low correspondence to the fauna of Spain (SpII) (14.5%), followed by the assemblages of Hungary, Bulgaria, and Ukraine. In addition to the Vitznau Marl corals, an account of all Valanginian coral faunas published before early 2021 is given, including their paleogeographic distribution, as well as their taxonomic and morphological characterization. For this preliminary study, a total of 206 coral species belonging to 97 genera found in the coral assemblages of the Valanginian were included. At both the genus- and the species-levels, colonial taxa are most abundant (colonial genera: 89%; colonial species 90%). The vast majority of the Valanginian genera already occurred in older strata. Only 11 genera (out of 97 = 11%) are newly recorded. The Valanginian faunas having the largest number of solitary taxa lived in both (sub-) paratropical to warm-temperate areas, and in arid regions. The coral faunas of the Valanginian are distinctly dominated by corals of well-established microstructural groups. Only 13% of the species from 24% of the genera belong to “modern” groups. Compared to the situation in the Berriasian which showed that 9% of the species and 17% of the genera belonged to modern microstructural groups, the occurrence of “modern” groups significantly increased during the Valanginian.
      PubDate: 2022-03-12
      DOI: 10.1186/s13358-021-00238-8
       
  • Fish otoliths from the middle Miocene Pebas Formation of the Peruvian
           Amazon

    • Free pre-print version: Loading...

      Abstract: Abstract A small assemblage of 22 otoliths was identified from the historical collection of Bluntschli and Peyer gathered in 1912 on the Itaya riverbank at Iquitos, Peru (Amazonia), from the Pebas Formation. The Pebas Mega-Wetland System in western Amazonia during the Miocene represented a unique, albeit short-lived, biotope characterized by a pronounced endemic evolution with gigantism in some vertebrate groups (e.g., turtles, crocodylians). Thus far, fishes have mainly been recorded based on isolated skeletal remains and teeth. Here, we describe the first well-preserved otolith assemblage from the Pebas Formation. This otolith assemblage adds a new facet to the fauna by complementing the skeletal bony fish data, primarily with species of the Sciaenidae and, to a lesser extent, Ariidae and Cichlidae. The sciaenids and ariids indicate that migration must have occurred between the marginal marine environments to the north and the Pebas Wetland System. The otoliths also indicate the likelihood of endemic developments of adapted marine immigrants to the Pebas Wetland System, some of which have become extinct (Pogonias, Umbrina), while others now represent typical South American freshwater fish groups (Plagioscion). Six new species are described based on otoliths, one in the Cichlidae—Cichlasoma bluntschlii n. sp., one in the Ariidae—Cantarius ohei n. sp., and four in the Sciaenidae—Pebasciaena amazoniensis n. gen. et n. sp., Plagioscion peyeri n. sp., Pogonias tetragonus n. sp. and Umbrina pachaula n. sp.
      PubDate: 2022-02-24
      DOI: 10.1186/s13358-022-00243-5
       
  • A large osteoderm-bearing rib from the Upper Triassic Kössen Formation
           (Norian/Rhaetian) of eastern Switzerland

    • Free pre-print version: Loading...

      Abstract: Abstract An important component of the Alpine vertebrate record of Late Triassic age derives from the Kössen Formation, which crops out extensively in the eastern Alps. Here, we present an isolated and only partially preserved large rib, which carries an osteoderm on a low uncinate process. Osteological comparison indicates that the specimen likely belongs to a small clade of marine reptiles, Saurosphargidae. Members of the clade are restricted to the western (today Europe) and eastern margins of the Tethys (today China) and were so far known only from the Anisian stage of the Middle Triassic. The assignment of the new find to cf. Saurosphargidae, with potential affinities to the genus Largocephalosaurus from the Guanling Formation of Yunnan and Guizhou Provinces, China, would extend the occurrence of the clade about 35 million years into the Late Triassic.
      PubDate: 2022-02-23
      DOI: 10.1186/s13358-022-00244-4
       
  • A historical vertebrate collection from the Middle Miocene of the Peruvian
           Amazon

    • Free pre-print version: Loading...

      Abstract: Abstract The Miocene aquatic and terrestrial fossil record from western Amazonia constitute a clear evidence of the palaeoenvironmental diversity that prevailed in the area, prior to the establishment of the Amazon River drainage. During the Miocene, the region was characterized by a freshwater megawetland basin, influenced by episodic shallow-marine incursions. A fossil vertebrate collection from the middle Miocene strata of the Pebas Formation is here studied and described. This historical collection was recovered in 1912 along the banks of the Itaya River (Iquitos, Peru), during a scientific expedition led by two scientists of the University of Zurich, Hans Bluntschli and Bernhard Peyer. Our findings include a total of 34 taxa, including stingrays, bony fishes, turtles, snakes, crocodylians, and lizards. Fishes are the most abundant group in the assemblage (~ 23 taxa), including the first fossil record of the freshwater serrasalmids Serrasalmus, and Mylossoma, and the hemiodontid Hemiodus for the Pebas system, with the latter representing the first fossil be discovered for the entire Hemiodontidae. The presence of a representative of Colubroidea in the middle Miocene of Iquitos supports the hypothesis of arrival and dispersal of these snakes into South America earlier than previously expected. This fossil assemblage sheds light on the palaeoenvironments, and the geographical/temporal range of several aquatic/terrestrial lineages inhabiting the Amazonian region.
      PubDate: 2021-12-20
      DOI: 10.1186/s13358-021-00239-7
       
  • Evolutionary development of the cephalopod arm armature: a review

    • Free pre-print version: Loading...

      Abstract: Abstract The cephalopod arm armature is certainly one of the most important morphological innovations responsible for the evolutionary success of the Cephalopoda. New palaeontological discoveries in the recent past afford to review and reassess origin and homology of suckers, sucker rings, hooks, and cirri. Since a priori character state reconstructions are still ambiguous, we suggest and discuss three different evolutionary scenarios. Each of them is based on the following assumptions: (1) Neocoleoidea uniting extant Decabrachia and Octobrachia is monophyletic (= proostracum-bearing coleoids); (2) extinct Belemnitida and Diplobelida are stem decabrachians; (3) proostracum-less coleoids (Hematitida, Donovaniconida, Aulacoceratida) represent stem-neocoleoids; (4) Ammonoidea and Bactritoidea are stem coleoids. We consider a scenario where belemnoid hooks derived from primitive suckers as well-supported. Regarding belemnoid hooks and suckers as homologues implies that belemnoid, oegopsid, and probably ammonoid arm hooks arose through parallel evolution. Our conclusions challenge the widespread opinion, whereupon belemnoid hooks evolved de novo, and instead support earlier ideas formulated by Sigurd von Boletzky.
      PubDate: 2021-12-20
      DOI: 10.1186/s13358-021-00241-z
       
  • The impact of the Pliensbachian–Toarcian crisis on belemnite
           assemblages and size distribution

    • Free pre-print version: Loading...

      Abstract: Abstract The second-order Pliensbachian–Toarcian crisis affected major groups of marine organisms. While its impact has been intensively studied for ammonites, the response of belemnites is only currently emerging through quantitative studies. Novel overall and regional diversity analyses suggest that belemnite richness in the NW-Tethys drops at the Pliensbachian–Toarcian boundary, while overall diversity slightly increases in NW-Tethys assemblages during the Toarcian Oceanic Anoxic event (T-OAE), mostly driven by NW European assemblages (e.g., Yorkshire). The T-OAE coincides with marked taxonomic turnover within individual basins, which is associated with an increase in median rostrum size of specimens in taxa at most localities. The changes in median body size across the Pliensbachian–Toarcian boundary are less consistent and driven by changes in body size within individual lineages crossing the boundary. However, our analyses also illustrate differences in sampling across the Pliensbachian–Toarcian crisis, which needs to be considered in further studies.
      PubDate: 2021-12-20
      DOI: 10.1186/s13358-021-00242-y
       
  • Novel insights into early life stages of finned octopods (Octopoda:
           Cirrata)

    • Free pre-print version: Loading...

      Abstract: Abstract The finned or dumbo octopods (Octopoda: Cirrata) constitute a cephalopod (Mollusca: Cephalopoda) taxon almost exclusively comprising organisms that inhabit the deep-sea. This renders studying the general biology of adult cirrate specimens a difficult task, but even more so when it comes to gathering knowledge on their early life stages. During his comprehensive research exploits on cephalopod development, the late Sigurd von Boletzky (1942–2020) also sought to shed light on specific adaptations that eggs and embryos of these enigmatic deep-sea octopods might show. Based on his seminal work, the present article sets out to provide additional data on a broad range of early cirrate life stages, including egg capsules without any obvious embryonic stage as well as those containing embryos. These previously unreported specimens obtained from museum collections were analyzed using conventional morphological as well as modern three-dimensional imaging techniques. The present overview includes specimens from four of the five oceans, i.e., the Atlantic, Pacific, Indian, and Southern Ocean. Based on information on cirrate ovum, chorion, and egg capsule size as well as shape gathered from the literature, an attempt is made here for the first time to identify von Boletzky's as well as the specimens introduced here down to at least genus level. The combined data provide novel insights into early life stages of finned octopods, aiming to continue von Boletzky's legacy with regard to developmental research on a still largely enigmatic taxon of extant deep-sea cephalopods.
      PubDate: 2021-12-20
      DOI: 10.1186/s13358-021-00240-0
       
  • A redescription of the Late Jurassic (Tithonian) turtle Uluops uluops and
           a new phylogenetic hypothesis of Paracryptodira

    • Free pre-print version: Loading...

      Abstract: Abstract We study the Late Jurassic (Tithonian) turtle Uluops uluops using micro-computed tomography scans to investigate the cranial anatomy of paracryptodires, and provide new insights into the evolution of the internal carotid artery and facial nerve systems, as well as the phylogenetic relationships of this group. We demonstrate the presence of a canalis caroticus lateralis in Uluops uluops, the only pleurosternid for which a palatine artery canal can be confidently identified. Our phylogenetic analysis retrieves Uluops uluops as the earliest branching pleurosternid, Helochelydridae within Pleurosternidae, and Compsemydidae including Kallokibotion bajazidi within Baenidae, which suggests at least two independent losses of the palatine artery within paracryptodires. We expect future studies will provide additional insights into the evolution of the circulation system of paracryptodires, as well as clarifying relationships along the turtle stem.
      PubDate: 2021-10-06
      DOI: 10.1186/s13358-021-00234-y
       
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
 


Your IP address: 18.208.187.128
 
Home (Search)
API
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-