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The Middle–Upper Triassic Aghdarband Basin, NE Iran, consists of a strongly deformed marine and non-marine stratigraphic succession, deposited along the southern margin of Asia in a highly complex tectonic context related to a back-arc setting. The youngest deformed units of the Aghdarband area consist of a rather monotonous sequence of brown-colored shales, with intercalations of siltstones and fine-grained sandstones forming the Miankuhi Formation. The shale-dominated Miankuhi Formation rests on an unconformity surface, separating it from the underlying Sina Formation. A multidisciplinary study based on sedimentological, palynological, and paleobotanical data permits to reconstruct the depositional environments, sedimentary evolution, and paleoclimate conditions of the upper Sina and the lowermost Miankuhi formations. The palynological association of the lowermost part of the Miankuhi Formation yielded sporomorphs of the latest early Carnian to early late Carnian age. Qualitative and quantitative analyses document a shift from xerophytic associations in the upper Ladinian (upper Sina Formation) to hygrophytic assemblages in the Carnian (lower Miankuhi Formation). This increase in hygrophytic elements is also observed in coeval Tethyan outcrops at the same latitudinal belt, suggests a more humid climate in the lower part of the Miankuhi Formation, and correlates this part of the succession with a record of the Carnian Pluvial Episode. The sedimentological and stratigraphical analyses show an evolution from prodelta to delta setting in the upper Sina Formation, then an unconformity enhanced by an interval of fluvial deposits with histosol levels in the basal Miankuhi Formation, in correspondence with the hygrophytic assemblages. The unconformable boundary between the Miankuhi and the Sina formations is, consequently, interpreted as a result of the sea-level fall associated with the humid climate shift, occurring in close association with the first effects of the Eo-Cimmerian Orogeny along the suture zone, taking to a regional reorganization of the basins architecture and the end of volcanic activity in the back-arc region. The main deformations related to the Eo-Cimmerian event thus, correspond in the Aghdarband Basin to the tectonic event that deformed the Miankuhi Formation. This event is probably older than the middle Norian (217.1 ± 1.7 Ma) but younger than the late Carnian, testifying to a diachronicity in the record of collision along the Iranian Cimmerian blocks and Southern Laurasia according to the different considered structural positions.

Spores or pollen from a single species or even an individual plant or sporangium may vary in morphology and size to a point that equivalent forms found dispersed in the sediment have been described as different species or even genera. In addition, not all these organs were mature at the moment of burial, and therefore they do not always contain completely developed microspores. To understand these variations better, we studied the intraspecific and interspecific morphological variability of in situ spores of leptosporangiate ferns (belonging to the Osmundales, possible Osmundales, and Gleicheniales) from the Triassic of Europe. The material comes from the Anisian Kuhwiesenkopf/Monte Pra della Vacca flora of Italy and the Carnian Lunz flora of Austria. Our analysis is aimed at distinguishing the normal range of variability, differentiating developmental stages, and determining the frequency of abnormal spores. Results show significant variation in both size and surface ornamentation of spores from the same sporangia, as well as between sporangia and individuals, which may have various causes. Abortive spores are usually rare but occurwith higher frequency in different samples from some specimens, suggesting that they can serve to identify systemic defects in the plants. (C) 2021 Published by Elsevier B.V.

The Anisian amber from the "Voltzia beds" of the Recoaro area, produced by Voltzia recubariensis, represents the most ancient Triassic amber known so far. The discovery of amber in the Anisian localities of Kühwiesenkopf/Monte Prà della Vacca and Piz da Peres, in the Dolomites area, fills a gap in the amber fossil record and contributes to the knowledge of Triassic amber. The finding of amber droplets, both dispersed in the sediment and anatomically connected to shoot fragments of V. recubariensis, demonstrates that during the Anisian this species was a resin-producer and that the favorable conditions for the preservation of resin and plant remains were present at regional scale. The contribution of Voltziales to Middle Triassic resin production in Northern Italy is also testified by the Ladinian amber from the "Wengener Schichten" of Wengen Formation, produced by Voltzia ladinica, whereas the Upper Triassic amber from Heiligkreuz Formation was mainly produced by cheirolepidiaceous conifers. The finding of an unidentified inclusion in the amber of Kühwiesenkopf/Monte Prà dalla Vacca is noteworthy, although difficult to interpret, and shows once again its capability to entrap and preserve witnesses of past life. Moreover, the correspondence between the Triassic amber occurrences and regional/global scale humid shifts, suggests a cause-and effect relationship, in which the rise of amber production/preservation potential is related to climate/environmental changes, particularly in marginal marine/coastal environments.

Altres ajuts: CERCA Programme/Generalitat de Catalunya The Cisuralian-Guadalupian (early-middle Permian) was a period of climate transition between the Carboniferous icehouse conditions to the latest Permian-Early Triassic hothouse. The landmasses had coalesced in the supercontinent Pangaea and the climate was progressively becoming more arid, especially in a belt over the palaeoequator. The deposits of present-day Mallorca (Balearic Islands, western Mediterranean) were located in those low palaeolatitudes, in the western margin of the Tethys Sea, and correspond to alluvial systems with meandering rivers. The present study divides the stratigraphic succession into three main units, formally described herein as the Bec de s'Àguila Formation, Port des Canonge Formation and Pedra de s'Ase Formation. Based on an exhaustive review of the literature and new magneto- and biostratigraphic data, the sequence has been dated between the early and middle Permian (Artinskian-Wordian). Moreover, the detailed study of the fossils has provided a complete account of the denizens of those ecosystems. Tetrapod tracks occur abundantly in the Port des Canonge Formation, with morphotypes attributed to moradisaurine captorhinid eureptiles, araeoscelidian diapsids/non-varanodontine varanopids, possible pareiasauromorph parareptiles, "pelycosaur"-grade synapsids and indeterminate synapsids. Spores and pollen grains from the Pedra de s'Ase Formation indicate an overall dominance of conifers, accompanied by sphenophytes, ferns and seed ferns. Overall, apart from providing the first detailed interpretation of the ecosystems of the Permian of Mallorca, these new data have made it possible to improve the characterisation of the Permian-Triassic tectonosedimentary cycle in the Balearic Islands, which contribute to the understanding of the evolution of the western peri-Tethys ecosystems.

The Aghdarband Basin in the Kopeh-Dagh Range (NE Iran) is one of the most important areas for unraveling the evolution of the Turan plate (southern margin of Eurasia) during the last phase of the closure of the Paleotethys and to reconstruct the history of the Cimmerian blocks just before their collision with Eurasia during the early Late Triassic. The youngest sediments affected by the Early Cimmerian orogeny are those of the Upper Triassic Miankuhi Formation, which covers unconformably the Upper Triassic (lower Carnian) marine beds of the Sina Formation by an interval of continental facies including local conglomerates, cross-bedded sandstones, mudstone layers, silty shales, an up to one-meter thick coal layer with plant remains, and shales. The plant assemblages represent a relatively wide variety of different forms (sphenophytes, ginkgophytes, conifers, and incertis sedis), documenting wetlands with lush vegetation typical of warm and humid environments. In this study, we describe a plant fossil assemblage from the base of the Miankuhi Fm., dominated by roots and vegetative organs of Neocalamites iranensis n. sp., with few plant fossils of uncertain botanical affinity. Palynological investigations of the basal part of the Miankuhi Formation confirm a latest early Carnian to late Carnian age for this interval and reveal, for the first time, a clear link between this plant-bearing bed, and a time of global environmental changes, the Carnian Pluvial Episode. This is the first report of the Carnian Pluvial Episode in the Turan plate (southern margin of Eurasia) and Iran., RIVISTA ITALIANA DI PALEONTOLOGIA E STRATIGRAFIA , V. 127 N. 2 (2021)

In 2016, two fossil marine reptiles were re-discovered in the collections of the Museo Civico di Storia Naturale di Verona. Originally recovered near Asiago, Vicenza province (northern Italy) from an outcrop of the Rosso Ammonitico Veronese Fm. (Middle-Upper Jurassic), they were never described. Morphological analysis carried out under UV-light allowed enhancing contrast with the surrounding matrix and better identifying some anatomical details. Both specimens consist of partially articulated postcranial elements from two distinct ichthyosaurs, including vertebrae, ribs, and some fragmentary elements of the appendicular skeleton. The first specimen V7101 is here tentatively assigned to Ophthalmosauridae based on a combination of features shared with other taxa in this family, such as the regionalization of the vertebral column. Taphonomical analysis suggests a long exposure of the carcass on the sea floor before burial; two teeth of the hexanchiform shark Notidanodon found near the ribcage could indicate scavenging. An ichthyosaur tooth most probably not belonging to the same specimen was found stuck on a rib and can also be attributed to scavenging - the first ever record of this interaction between two ichthyosaurs. The second specimen V7102 is represented by a poorly preserved partial vertebral column and is here referred to Ichthyosauria indet. due to the absence of taxonomically significant characters. Calcareous nannofossil data and microfacies analyses allow us to assign both specimens to the basal Kimmeridgian. This makes the two Notidanodon teeth associated with V7101 the oldest recorded occurrence of this genus.

The Carnian Pluvial Episode was a phase of global climatic change and biotic turnover that occurred during the early Late Triassic. In marine sedimentary basins, the arrival of huge amounts of siliciclastic sediments, the establishment of anoxic conditions, and a sudden change of the carbonate factory on platforms marked the Carnian Pluvial Episode. The sedimentary changes are closely associated with abrupt biological turnover among marine and terrestrial groups as, for example, an extinction among ammonoids and conodonts in the ocean, and a turnover of the vertebrate fauna and the flora on land. Multiple negative carbon-isotope excursions were recorded during the Carnian Pluvial Episode in both organic matter and marine carbonates, suggesting repeated injection of 13C-depleted CO2 into the ocean–atmosphere system, but their temporal and causal links with the sedimentological and palaeontological changes are poorly understood. We here review the existing carbon-isotope records and present new data on the carbon-isotope composition of organic carbon in selected sections of the western Tethys realm that record the entire Carnian Pluvial Episode. New ammonoid, conodont and sporomorph biostratigraphic data were collected and coupled to an extensive review of the existing biostratigraphy to constrain the age of the sampled sections. The results provide biostratigraphically constrained composite organic carbon-isotope curves for the Carnian, which sheds light on the temporal and causal links between the main carbon-isotope perturbations, and the distinct environmental and biotic changes that mark the Carnian Pluvial Episode. The carbon-isotope records suggest that a series of carbon-cycle perturbations, possibly recording multiple phases of volcanic activity during the emplacement of the Wrangellia Large Igneous Province, disrupted Carnian environments and ecosystems repeatedly over a remarkably long time interval of about 1 million years.

A transition from widespread humid to more drought tolerant floras characterized tropical terrestrial ecosystems during the Permian (Cisuralian). Tregiovo (Southern Alps, N-Italy) is one of the very few well dated Kungurian (late Cisuralian) plant localities in Euramerica. It was located in eastern palaeoequatorial Pangea. Two units bearing fossil plant assemblages occur in finely laminated sediments deposited in a playa-lake environment. In this paper, the sedimentology of the Tregiovo Basin is reviewed, and new palaeobotanical, palynological and stable isotopic data are presented, in order to reconstruct the palaeoclimatic and palaeoenvironmental conditions of the Kungurian in the Southern Alps. Both fossil plant assemblages are dominated by conifers (Hermitia, Feysia, Quadrocladus, Dolomitia), together with sphenophytes (Annularia), ginkgophytes (Sphenobaiera), pteridosperms (Peltaspermum), taeniopterids and sphenopterids. These taxa, which occur with different abundances in the two plant assemblages, both indicate semi-arid conditions. Associated palynofiora, dominated by bisaccate pollen, and extremely rare spore occurrences, is consistent with the xerophytic character of the macroflora, and suggests that the fossil plant record was not affected by collection or preservation bias. Stable isotopic analyses of two stratigraphic sections reveal an upward trend of increasingly negative delta C-13(org) (VPDB), which may correlate with roughly coeval records from marine and continental successions such as in North China and South Africa. This isotopic shift may be attributed to a global perturbation of atmospheric delta C-13, although the influence of local environmental factors cannot be excluded.

The complex European–Adria geodynamic framework, which led to the formation of the Alpine belt, is considered responsible for the orogenic magmatism that occurred in the Central Alps along the Periadriatic/Insubric Line (late Eocene–early Oligocene) and the anorogenic magmatism that occurred in the Southeastern Alps (late Paleocene–early Miocene). While the subduction-related magmatic activities are, as expected, near convergent margins, the occurrence of the intraplate-related magmatism is still puzzling. Therefore, in this work new geochemical and geochronological data of magmatic products from the Veneto Volcanic Province (VVP, north–east Italy) are provided to constrain the Cenozoic intraplate magmatism of the Southeastern Alps. The VVP is formed by dominant basic–ultrabasic (from nephelinites to tholeiites) magmatic products and by localized acid (latitic, trachytic, and rhyolitic) volcanic and subvolcanic bodies. Trace element patterns and ratios suggest that the mantle source of the alkaline magma types was a garnet lherzolite possibly metasomatised by carbonatitic melts and with residual phlogopite. According to the biostratigraphic records and our new 40Ar/39Ar ages, VVP eruptions occurred in several pulses, reflecting the extensional phases experienced by the Eastern Alpine domain. The volcanism started in the late Paleocene in the western sector of the VVP where activity was widespread also during the Eocene (45.21 ± 0.11 Ma – 38.73 ± 0.44 Ma). In the eastern sector eruptions took place in the early Oligocene (32.35 ± 0.09 Ma – 32.09 ± 0.29 Ma) and in the early Miocene (~23–22 Ma). From the studies so far undertaken, the anorogenic magmatic activity of the VVP was interpreted as resulting from mantle upwellings through slab window(s) following the European slab break-off, which occurred at ~ 35 Ma. However, considering (i) new tomographic images evidencing a continuous subvertical (~ 500 km in depth) slab beneath the Central Alps, and (ii) the onset of magmatic activity in the VVP in the late Paleocene (i.e., before the slab break-off) and its continuation until the Miocene, a better suited geodynamic scenario is required to explain the anorogenic magmatism. The westward rollback of the European slab caused the retreat and steepening of the subducting plate. As a consequence, sub-slab mantle material escaped and upwelled from the front of the slab and created a poloidal mantle flow. The latter induced the breakdown of carbonates in calcareous metasediments and carbonated metabasics within the subducting oceanic slab, providing carbonatitic melts, which could be responsible for the metasomatism of the VVP mantle sources. After that, the poloidal mantle flow also induced (i) the extensional deformation in the overriding Adria microplate, (ii) the decompressional melting of VVP mantle sources, and (iii) the intraplate affinity of the VVP magmatism. During these processes, the Adria microplate also rotated counterclockwise, forming sedimentary basins, and allowing the poloidal mantle flow to affect different portions of the overlying lithosphere, generating syn-estensional magmatism within the VVP.

The End-Triassic Extinction event (ETE) has been recognized in numerous sections worldwide and it is usually marked by three negative carbon isotope excursions (NCIEs), named “precursor” (P-NCIE), “initial” (I-NCIE) and “main” (M-NCIE) negative carbon isotope excursions. These three NCIEs are significant characteristics of this time interval, and they are likely related to the emplacement of the Central Atlantic Magmatic Province (CAMP) that is considered the main trigger of the ETE. Stable carbon isotope excursions, commonly related to biotic turnovers and extinctions, play an important role in stratigraphic correlations, particularly around the Triassic-Jurassic boundary (TJB). This time interval records the disappearance of conodonts, elements of a feeding apparatus belonging to marine organisms that populated the Paleozoic-early Mesozoic seas, and which became extinct across the TJB. So far, the interpretation of conodont extinction has remained ambiguous, as the timing of its last occurrence was debated which in turn hindered our understanding of the main cause(s) that could have led to their disappearance. Here we present and compare integrated data of nine TJB sections from different areas, Tethys and Panthalassa, and different depositional environments, i.e. shallow vs deep water or proximal vs distal shelf. Each of these sections record both the last occurrences of latest Triassic conodont taxa and pronounced changes in the carbon isotopic composition of organic matter across the TJB interval. Our analysis of chemo- and integrated biostratigraphic correlation suggests that the final extinction of the taxon Conodonta was asynchronous.

The Rotzo Formation is famous for its Lower Jurassic terrestrial flora and marine (invertebrate) and terrestrial (dinosaur footprint) fauna. However, lycophyte macrofossils were never described from this time period in Italy, although palynological analyses yielded abundant lycophyte spores. Dispersed megaspores, in association with charcoal and amber drops, were recently collected from several horizons and outcrops of the Monte Lessini area. Sedimentological and palaeontological data reconstruct the palaeoenvironment as a paralic swamp under a warm and humid (monsoonal) climate. This is the first record of Jurassic megaspores from Italy, increasing our understanding of Jurassic lycophyte diversity, since at least five microspore and five megaspore genera with selaginellalean botanical affinities can be distinguished. Moreover, this underlines how well these brackish environments were adapted for the preservation of fossil plant remains (including amber).

Amber from the Carnian succession of the Dolomites and Julian Alps (northeastern Italy) represents one of the most ancient and quantitatively substantial Triassic fossil resin records in the world. So far, the Carnian appeared to be the only Triassic stage with findings of amber remains. However, the recent reappraisal of historical collections of plant fossils led to the discovery of even older Triassic amber, found on a rock slab from the "Voltzia beds" of the Recoaro area (Anisian) and on a sample from the "Wengener Schichten" of Wengen/La Valle (Ladinian), respectively. Both specimens are associated with conifer shoots of Voltziales. To date, they are the oldest known Triassic fossil resins, demonstrating that the preservation of amber was not restricted to the sediments deposited during the Carnian as suggested before. These finds contribute to partially fill the gap in the amber record between the Carboniferous and Upper Triassic.

An integrated sporomorph and ammonoid biostratigraphy has been carried out in three upper Anisian (Middle Triassic) stratigraphic sections in the Southern Alps (Italy). Two main sporomorph assemblages have been defined and calibrated with ammonoids. The TrSM-A assemblage is marked by the co-occurrence of Stellapollenites thiergartii, Dyupetalum vicentinense, Cristianisporites triangulatus and Staropollenites antonescui. The TrSM-B assemblage is marked by the first occurrence of Cannanoropollis scheuringii. The boundary between the TrSM-A and TrSM-B assemblages falls in the upper part of the reitzi ammonoid subzone (Hungarites zone; Illyrian). The TrSM-A and TrSM-B assemblages have been compared and correlated with other existing sporomorph biozonations for the northwestern Tethys, the Germanic Basin and the Barents Sea. The first occurrence of the genus Ovalipollis is recorded within the assemblage TrSM-A, in the lower-middle reitzi ammonoid subzone. Quantitative palynological data coupled with previously published studies show a shift from hygrophytic to xerophytic elements in the trinodosus-lower reitzi ammonoid subzones. This change in precipitation range can be recognised in other sections in the northwestern Tethys but seems to have preceded a similar shift recorded in the Boreal realm.

Hemipelagic dark limestones within calciturbiditic deposits at Monte Solane in the western Lessini Mountains of northern Italy yield a fish fauna dominated by stomiiforms. A minor component of the fossil assemblage is represented by a macroalgal non-calcareous flora associated with rarer terrestrial components including few angiosperm leaves and seeds. Micropaleontological (foraminifera, dinoflagellate cysts), sedimentological and geochemical proxies (TEX86) indicate a deposition of the fossil-bearing bed in a hypoxic to possibly anoxic, warm, restricted basin. High-precision dating based on rich foraminiferal and calcareous nannoplankton content allows ascribing the site to the upper part of the Ypresian (Lower Eocene). The site is slightly older than the Ypresian worldwide-famous shallow-water Bolca Konservat-Lagerstatte located in the same region. Convergent paleoenvironmental clues based on both microfossils and ichthyofauna indicate that the sediments were deposited in the upper bathyal zone, probably between 300 and 600 m. Solane is therefore one of the rare and precious Eocene Lagerstdtte to have fossilized in a deep marine setting. The site contains the oldest Cenozoic record of an ichthyofauna dominated by meso-bathypelagic taxa. (C) 2014 Elsevier B.V. All rights reserved.