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Fish otoliths from three localities in northern Italy (Piedmont), Grazzano, Rio Freddo di Albugnano and Valle Ceppi, ranging in age from late Oligocene (Chattian) to Early Miocene (Burdigalian) are described herein. One of these localities, Rio Freddo di Albugnano, straddles the Oligocene/Miocene boundary, and the otoliths are interpreted to reflect a late Oligocene age. The other two localities are from the upper Burdigalian (Lower Miocene). The otolith assemblages described herein complement previously described associations from the northern Mediterranean region and contain a total of 68 species-level taxa, 16 of which are new and 12 remain in open nomenclature. The upper Oligocene strata yielded 24 species and the Lower Miocene strata 48 species; four species are shared. The results are compared with previous studies and discussed. Deepwater taxa are abundant in the assemblages, particularly those pertaining to the mesopelagic family Myctophidae. The otolith assemblage fills a stratigraphic gap in the record of this family in Europe and thus contributes to refinement of stratigraphic ranges of myctophid species. The otolith assemblages are also compared with coeval assemblages known from other regions of the world and their paleobiogeographic significance is discussed. Myctophid species particularly show often a very wide geographic distribution pattern across ocean basins during the Miocene similar to that characteristic of this family today. In combination with refined stratigraphic ranges of myctophid species, this wide geographic distribution could ultimately become useful as a biostratigraphic tool in a supra-regional perspective. [ABSTRACT FROM AUTHOR]

New evidence for a biostratigraphic assessment of the limestone succession comprising K-bentonite levels exposed in the Yılanlı Formation of the Istanbul-Zonguldak Terrane are provided from conodonts at the Gavurpınarı quarry in Bartın area (NW Turkey). The succession depicts a shallow marine, nearshore facies setting that comprises rare and low diversity conodont associations mainly exemplified by the species of Ctenopolygnathus, Icriodus and Polygnathus. Conodont faunas from the lower part of the section are of late Frasnian age, including the taxa Icriodus subterminus Youngquist, 1947, Polygnathus aff. xylus Stauffer, 1940, Icriodus iowaensis iowaensis Youngquist & Peterson, 1947 and Ctenopolygnathus brevilaminus Branson & Mehl, 1934, and the upper part is assigned to early Famennian marked by the first appearance of Icriodus cornutus Sannemann, 1955. The local biostratigraphic framework of the Yılanlı Formation is correlated with the upper Frasnian Lower rhenana to the lower Famennian Middle triangularis standard conodont zonations. Considering the described species, the Frasnian-Famennian boundary corresponds to a slight change in conodont fauna and is assigned within the local Icriodus iowaensis iowaensis Zone. Accordingly, the novel K-bentonite age data potentially indicates the evidence for the Kellwasser events in northern Turkey, improving paleogeographic correlations of the Istanbul-Zonguldak Terrane with other terranes in Laurasia and Peri-Gondwana. [ABSTRACT FROM AUTHOR]

New data (onshore, offshore) on the Upper Cretaceous Ilam Formation of southwestern Iran are provided concerning the common presence of dasycladalean green algae (families Triploporellaceae, Polyphysaceae) that have so far been treated mostly in open nomenclature. The assemblage consists of the five taxa Salpingoporella ubaiydhi Radoičić, 1979, Dissocladella ondulata (Raineri, 1922), Trinocladus tripolitanus Raineri, 1922, Clypeina cf. dusanbrstinai Radoičić, 1997, and gen. et sp. indet. The taxa typically prevail in wackestones-packstones but exhibit different distributional patterns. While S. ubaiydhi and T. tripolitanus, rarely associated with D. ondulata, form a characteristic assemblage in a distal infralittoral facies (more diverse assemblage; zone no. 31 of Wynd, 1965), C. cf. dusanbrstinai occurs in a proximal infralittoral facies associated with miliolids among also complex forms (rhapydioninids) (assemblage zone no. 30 of Wynd, 1965). It is concluded that the two assemblage zones refer to different palaeoenvironments, instead of different ages ('lower' and 'upper'). Based on benthic foraminifera, the main part of the Ilam Formation can be ascribed to the Santonian. For the lower part, a late Coniacian age is suggested implied indirectly by the comparably long vertical range of the rotaliid Orbitokathina vonderschmitti Hottinger, 1966 of the studied core. This would be in conformity with the K 150 Arabian Plate K 150 sequence boundary referring to a late Turonian?-early Coniacian hiatus. From a palaeobiogeographic perspective, T. tripolitanus is a cosmopolitan species, S. ubaiydhi is restricted to the area of the former Arabian Plate (subsurface Iraq, Saudi Arabia and Egypt), while C. dusanbrstinai has been recorded only from Serbia (type-locality). In addition to the algae, the stratigraphic discussion includes the occurrence of the benthic foraminifera Reticulinella? kaeveri Cherchi, Radoičić & Schroeder, 1989 and Orbitoides mid-orientalis (Eames & Smout, 1956) in the Ilam Formation. [ABSTRACT FROM AUTHOR]

The acritarch genus Cyclopsiella is extant and ranges back to the Middle Jurassic. This genus cannot be assigned to any of the established acritarch subgroups and has a relatively simple morphology; species are often referred to using open nomenclature. This study provides a comprehensive analysis of Cyclopsiella and its different morphotypes and species, outlining their characteristics and similarities. Through an extensive literature review, this study identifies previous sources of taxonomic confusion, reevaluates the characteristics and stratigraphical utility of this genus, and discusses the significance of the constituent species for Mesozoic and Cenozoic biostratigraphy. A series of synonymies and emendations are proposed, and 10 species of Cyclopsiella are maintained. One new species, Cyclopsiella reticulata sp. nov., is described. This robust morphological investigation strengthens the biostratigraphical and palaeoecological potential of Cyclopsiella. [ABSTRACT FROM AUTHOR]

A study in Simeh-Kuh, northern Iran, focuses on Ordovician strata, documenting acritarchs and chitinozoa, and has helped to understand ancient environments. The aim is chronostratigraphical calibration, using palaeontological data including brachiopods, trilobites, and graptolites. Ninety-three surface samples were collected and analysed, yielding a rich collection of 117 morphotypes, including 59 acritarch species and 58 chitinozoan species. Eight acritarch assemblage biozones (A–H) and 14 chitinozoan biozones (1–14) were established. Biozones A–F indicate Late Cambrian to Middle Ordovician ages in the Lashkarak Formation, while biozones G–H indicate the Late Ordovician in the Ghelli Formation. The Eremochitina brevis-Linochitina pissotensis biozones suggest late Floian to late Darriwilian ages, and the Belonechitina robusta-Armoricochitina nigerica biozones support a Late Ordovician age. These findings place the Alborz Mountains in the North Gondwana Domain during the Ordovician. Palynomorphs with a thermal alteration index of 4.0–4.5 indicate overmature organic matter in Lower Palaeozoic deposits, potentially linked to the Ordovician metamorphic event in the southern Caspian Sea. Additionally, four new species were identified: Cyathochitina sp. A, Tanuchitina hosseini-nezhadi sp. nov., Dactylofusa kazzazii sp. nov., and Inflatarium alborzensis sp. nov. Highlights: A palynological study at Simeh-Kuh in the Alborz Mountains, northern Iran has uncovered a richly preserved assortment of Cambrian–Ordovician acritarchs and chitinozoa. Fifty-eight chitinozoan species, spanning 22 genera, were identified from the Lashkarak and Ghelli formations at Simeh-Kuh. This facilitated the delineation of 14 distinct chitinozoan biozones. Fifty-nine acritarch species across 33 genera were identified from the Late Cambrian to Late Ordovician strata, contributing to recognising eight distinct assemblage biozones. The Lashkarak Formation has yielded four distinctive acritarch genera: Arbusculidium, Coryphidium, Striatotheca, and Arkonia. These genera hold notable significance as they are characteristic elements of the Peri-Gondwanan palaeoprovince. The identification of chitinozoans in the Lashkarak and Ghelli formations has facilitated the establishment of 14 chitinozoan biozones. Notably, these biozones are considered classical elements of the Northern Gondwana Domain/Peri-Gondwana palaeoprovince. The Belonechitina robusta, Tanuchitina fistulosa, Acanthochitina barbata, and Armoricochitina nigerica biozones were recognised in the Ordovician deposits at Simeh-Kuh. This discovery marks the region's first confirmation of Sandbian–Katian strata. A significant hiatus exists between the Ghelli and Geirud formations, spanning the Late Ordovician (latest Katian–Hirnantian), Silurian, and Early–Middle Devonian periods. Four new species have been established: Cyathochitina sp. A, Tanuchitina hosseini-nezhadi sp. nov., Dactylofusa kazzazii sp. nov., and Inflatarium alborzensis sp. nov. [ABSTRACT FROM AUTHOR]

ABSTRACT This is a comment on the paper of Singh et al. (Geological Journal, 2024:1–20) on Strontium isotope stratigraphy of marine Oligocene–Miocene sedimentary successions of Kutch Basin, western India. Kutch hosts stratotypes of some lithostratigraphic and chronostratigraphic units of India. In this study, the Sr‐isotope estimated ages of the studied formations deviate significantly from their known ages based on biostratigraphy. The authors have not validated the interpreted ages with biostratigraphy. We believe a scrupulous screening of samples and validation of Sr‐isotope data with biostratigraphy are two essential requirements of Sr‐isotope stratigraphy. Unfortunately, Singh et al. made a new contribution to Kutch stratigraphy that falls short of meeting both conditions, leading to incorrect ages of the regional chronostratigraphic units of India. [ABSTRACT FROM AUTHOR]

Under Priabonian (latest Eocene) far-field compression, the major Jurassic graben systems and their proximal areas experienced domal uplift in the Netherlands and northeastern Belgium. It has been proposed that this flexural uplift was simultaneous with flexural subsidence of the surrounding areas. This hypothesis is, however, only based on the correlation of few widely spaced boreholes without supporting biostratigraphic or seismic data. For this study, a seismic line and cross-boundary borehole log correlation panel, comprising three biostratigraphically analyzed boreholes, were used to critically examine the abovementioned hypothesis. The seismic line and correlation panel run from the southern flank of the uplifted West Netherlands Basin, also known as the Voorne Trough, towards the south. They both show a gradual thickening of the Priabonian sequences towards the Voorne Trough, confirming the flexural subsidence hypothesis. The underlying Bartonian and overlying lowermost Rupelian units do not share the abovementioned thickness trend, which highlights the particularity of Priabonian basin dynamics. Within the Priabonian depocenter, plenty of reworked organic material was deposited, mostly of Bartonian age, providing further evidence of the simultaneity of subsidence and uplift in nearby regions. We consider it very likely that subsidence and uplift were part of the same vertical surface deformation process. The results of this study are consistent with the mechanism of lithospheric folding under far-field compression by the convergence between Africa and Europe. A Priabonian N-S compressional stress-field would also be consistent with fault, joint and vein analyses performed at the British Isles west of the study area. As the regional stress-field changed around the Eocene–Oligocene boundary, the vertical surface movements of the study area also changed. [ABSTRACT FROM AUTHOR]

Spalacinae are an unusual component of the fossil record around the world with a limited geographical distribution. The revisited section of Afşar includes one of the richest collections of Spalacinae in Turkey. From Afşar 1, near the base of the section we recovered Pliospalax cf. macoveii while in Afşar 2, at the top of the section we distinguish the species P. tourkobouniensis. The current research includes the first record of the last-mentioned species outside of Europe. Both spalacines indicate a dry and open space environment and, in accordance with the Arvicolinae, suggest that Afşar 1 can be attributed to MN 15 while Afşar 2 is correlated to MN 16. [ABSTRACT FROM AUTHOR]

This study presents the first U-Pb (CA-ID-TIMS) radioisotopic dating of zircon grains extracted from tonsteins within the uppermost Permian coal interval of the Minusinsk Coal Basin (Siberia, Russia). Petrographic, structural, and mineralogical analyses confirm the volcanic ash origin of the tonsteins. The parent pyroclastic materials are identified as rhyolite–pantellerite for tonstein I-22 and dacite–rhyodacite for tonstein I-12. Morphological analysis of zircon crystals, along with cathodoluminescence and melt inclusion studies, confirms their volcanic origin and crystallisation temperatures of 700–900 °C. New radioisotopic dates of 261.4 ± 0.7 Ma and 261.3 ± 0.4 Ma clarify the age of the Izykh Formation, enabling its direct correlation with the Capitanian Stage of the International Chronostratigraphic Chart. The results emphasise the possible discontinuity of the coal-bearing succession of Siberian palaeocontinent and highlight the potential for further stratigraphic refinement through continued radioisotopic dating of tonsteins. [ABSTRACT FROM AUTHOR]

To study diatoms from some Neogene stratotype sections of Southern Primorye—the Sineutesovskaya and Novokachalinskaya formations and the Shufansky Horizon, light and scanning electron microscopy were used. The data allowed corrections to the existing Zonal Diatom Scale of the Neogene of Primorye. Studies have shown the absence of some zone index species in the deposits: Alveolophora bifaria, A. jouseana, and A. areolata. As a result, the subdivisions of the scale were renamed: Alveolophora hachiyaensis–Aulacoseira elliptica Zone, Alveolophora khankaica Zone, Alveolophora khursevichiae Zone. The position of the Shufansky horizon zones has changed: the Aulacoseira praeislandica Zone now corresponds to the Early Pliocene, and the Alveolophora tscheremissinovae Zone—to the Late Pliocene. According to the International Stratigraphic Chart of the Cenozoic, the age of the upper boundary of the Alveolophora tscheremissinovae Zone is 2.58 Ma. [ABSTRACT FROM AUTHOR]

Coastal sediment stratigraphies, their physical properties and microfossil assemblages are commonly used to reconstruct sea-level change. However, coastal sediments are affected by tidal, wave, aeolian, and overwashing processes at a range of elevations both within and above the tidal frame which means that their sea-level signatures may not always be clearly identified. Saltmarsh is a common coastal sedimentary environment along the Atlantic-facing coastline of northwest Ireland where bedrock headlands and an archipelago of small offshore islands have provided accommodation space for aggradational Holocene sediment sequences. A 2.85 m-long sediment sequence was investigated at Cloughglass, northwest Ireland. This shows weathered granite bedrock overlain by glacigenic cobbles and then in situ Pinus stumps within humified peat that is exposed in the upper foreshore. Above this, organic-rich and laminated saltmarsh sediments are arranged in packages (20–80 cm thick) bounded by undulating erosional surfaces. The saltmarsh sediments are unconformably overlain by a palaeosol (30 cm thick) and 1.5 m of recent dune sand. Sediment samples were removed at 5 cm intervals through the entire logged section and analysed for grain size properties, combustible organic content, CaCO 3 content, and microfossil assemblages. Five samples were dated by the AMS 14C method. Results show organic sediment accumulated around the pine tree stumps at ∼4400 cal yr BP but that later sedimentation was episodic, as evidenced by erosional surfaces throughout the saltmarsh part of the succession that may correspond to episodic storms or flood events. Three microfossil biostratigraphic zones are identified which broadly correspond to the sediment stratigraphy. The lowermost zone has poor preservation. The middle zone contains several halophytic species in low abundance but is dominated by the ubiquitous diatom Achnanthidium minutissimum. The uppermost zone is less diverse, with low but consistent abundance of predominately freshwater species and those that can tolerate brackish conditions. Integrating these results suggests that late Holocene coastal erosion and sea-level rise brought the coastline closer to the site over time, with a concomitant increase in wave and tidal influence as recorded in both sedimentary structures and biofacies. Subsequently, the land surface became stabilized with development of a dune palaeosol and decreased abundance of A. minutissimum. This evolutionary history reflects changing patterns of wave exposure and sediment supply as a result of changes in sand accumulation around the surrounding bedrock islands. Thus, the coastal stratigraphy more strongly reflects local sediment dynamics and accommodation space rather than regional sea-level change in the late Holocene. [ABSTRACT FROM AUTHOR]

New data obtained from core samples of two boreholes and dredged samples from the Alba Guyot in the Magellan Seamount Trail (MST), Western Pacific, including the 40Ar/39Ar age determinations of basanite, and the mineralogy of basanite, tuff, tuffite, mantle-derived inclusions in basanite and tuff (lherzolite xenolith and Ol, Cpx, and Opx xenocrysts), and calcareous nannofossil biostratigraphy, have implications for the guyot′s development and history. Volcanic units in the upper part of the Alba Guyot main edifice and its Oma Vlinder satellite, at sea depths between 3600 and 2200 m, were deposited during the Cretaceous 112 to 86 Ma interval. In the following ~60 myr, the Alba Guyot became partly submerged and denuded with the formation of a flat summit platform while the respective fragment of the Pacific Plate was moving to the Northern Hemisphere. Volcanic activity in the northeastern part of the guyot summit platform was rejuvenated in the Miocene (24–15 Ma) and produced onshore basanitic volcanoes and layers of tuff in subaerial and tuffite in shallow-water near-shore conditions. In the Middle-Late Miocene (10–6 Ma), after the guyot had submerged, carbonates containing calcareous nannofossils were deposited on the porous surfaces of tuff and tuffite. Precipitation of the Fe-Mn crust (Unit III) recommenced during the Pliocene–Pleistocene (<1.8 Ma) when the guyot summit reached favorable sea depths. The location of the MST guyots in the northwestern segment of the Pacific Plate near the Mariana Trench, along with the Miocene age and alkali-basaltic signatures of basanite, provide first evidence for petit-spot volcanism on the Alba Guyot. This inference agrees with the geochemistry of Cenozoic petit-spot basaltic rocks from the Pacific and Miocene basanite on the Alba Guyot. Petit-spot volcanics presumably originated from alkali-basaltic melts produced by decompression partial melting of carbonatized peridotite in the metasomatized oceanic lithosphere at the Lithosphere–Asthenosphere Boundary level. The numerous volcanic cones with elevations of up to 750 m high and 5.1 km in basal diameter, discovered on the Alba summit platform, provide the first evidence of voluminous Miocene petit-spot basanitic volcanism upon the Cretaceous guyots and seamounts of the Pacific. [ABSTRACT FROM AUTHOR]

Traversodontid cynodonts are one of the most abundant and diverse groups of tetrapods in the Triassic assemblages of Brazil. These cynodonts are distributed across four Brazilian Assemblage Zones (AZ), ranging from the late Ladinian to the early Norian. The most taxonomically diverse record comes from the Dinodontosaurus AZ, which has so far yielded at least six traversodontid genera. Among these taxa, Protuberum cabralense represents one of the most bizarre forms. This cynodont is characterised by the presence of enlarged and rounded protuberances along the dorsal surface of the ribs, the vertebral neural spines and dorsal portion of the iliac blades. These structures have been suggested to serve as a defensive mechanism or related to burrowing/digging habits. We report the first occurrence of P. cabralense at the Linha Várzea 1 site, located in the municipality of Paraíso do Sul, Brazil. This site is considered late Ladinian to early Carnian in age. The new material consists of five rib fragments, which possess the characteristic protuberances on their dorsal surface. A biostratigraphic investigation demonstrates the absence of P. cabralense in fossiliferous sites that yielded the cynodonts Luangwa. This observation contributes to the discussion regarding a potential subdivision within the Dinodontosaurus AZ. [ABSTRACT FROM AUTHOR]

The most common age constraint for the diatomaceous sediments is biostratigraphy of siliceous microfossils. Although biostratigraphy is a powerful tool to establish stratigraphy and correlate with sedimentary sequences in other sites, biostratigraphy generally includes uncertainties difficult to evaluate. In this study, we measured zircon U–Pb ages of eight tuff beds intercalated with diatomaceous mudstone of the Nakayama Formation on Sado Island in Central Japan and integrated the U–Pb ages with diatom and radiolarian biostratigraphy, whose ages and errors were re-evaluated by this study, to establish an age model precisely representing the sedimentary age. Two tuff beds in the upper and middle part of the formation offered zircon U–Pb ages of 6.7 ± 0.2 Ma and 10.87 ± 0.07 Ma, which are consistent with biostratigraphy, and provided a good example of effective integration of zircon U–Pb ages with the biostratigraphy. On the other hand, zircon U–Pb ages of the other six tuff beds in the lower part are around 12 Ma and not distinguishable from each other. In addition, older zircon grains in the 6 tuff beds are assembled in the interval from 30 to 20 Ma, which is consistent with the age of the volcanic basement rocks forming most part of Sado Island. Similarities in chemical compositions of glass shards and age distributions of zircon grains indicate that the volcaniclastic components in the tuff beds should originate from single or associated magmatic activities. [ABSTRACT FROM AUTHOR]

The Burdigalian/Langhian (B/L) boundary has not yet been designated as a Global Stratotype Section and Point (GSSP), despite various proposed zonal schemes. In the Gulf of Suez region of Egypt, the Burdigalian-Langhian successions are notable for hosting significant hydrocarbon reservoirs within a tectonic rift setting. Therefore, biostatigraphy plays a crucial role in exploration endeavors in this area. The nannofossil biostratigraphy is investigated in two sections, Wadi Baba and Wadi Gharandel, of the lower-middle Miocene from west-central Sinai. Three biozones, NN3 (Sphenolithus belemnos) Zone, NN4 (Helicosphaera ampliaperta) Zone, and NN5 (Sphenolithus heteromorphus) Zone, are identified from the studied interval. The NN4 Zone could be divided into MNN4a/b and MNN4c. Important biovents are discussed, such as the S. heteromorphus paracme interval and the first occurrence and evolution of the Discoaster exilis and Discoaster variabilis groups. Based on the cluster analysis, the recorded taxa can be subdivided into four groups that reflect their palaeoclimatic preferences. The paleoecological interpretation of the studied Rudies Formation indicates prevailing cool and eutrophic nutrient conditions based on the dominance of taxa such as Coccolithus pelagicus, Reticulofenestra minuta, and Cyclicargolithus floridanus. The nannofossil taxa responses to sea level curve are interpreted. Fluctuations in taxa abundance and diversity indicate a slight rise in the sea level at the base of the Burdigalian followed by sudden drop in the sea level at the middle Burdigalian. High sea-level conditions prevailed again until the B/L boundary. During the Langhian period, many small-scale fluctuations in sea-level curve are detected. [ABSTRACT FROM AUTHOR]

Lithological cycles with a repetitive pattern of sandstone overlain by limestone or shale comprise the middle Minnelusa Formation in the Black Hills region, USA. At least eight lithological cycles were observed at Boulder Canyon Road (BCR), eight at Vanocker Canyon Road (VCR) and four at Hot Brook Canyon (HBC). These rocks were deposited in a nearshore to offshore marine environment, and the shale and limestone intervals at the top of these cycles yielded conodonts. Five biostratigraphically distinct Middle to Upper Pennsylvanian conodont faunas were recovered from these marine units. An upper Desmoinesian assemblage was recovered from VCR cycle 1. Two Missourian assemblages were recovered, one indicative of the Idiognathodus cancellosus Zone from VCR cycle 3 and the other indicative of the Streptognathodus gracilis Zone from VCR cycle 6. Two Virgilian assemblages were recovered, one indicative of the Heckelina simulator Zone from VCR cycle 7, VCR cycle 8 and HBC cycle 2 and the other indicative of the lower part of the "Streptognathodus" group 4 virgilicus Zone from HBC cycle 3. Two conodont biofacies were recognized within the middle Minnelusa, the low energy, offshore, Idiognathodontidae-Idioprioniodus biofacies and the higher energy, nearshore Idiognathodontidae-Hindeodus biofacies. [ABSTRACT FROM AUTHOR]

A reliable character system is crucial to taxonomy and systematics, and it promises valid downstream inferences, e.g., estimates of diversity and disparity, reconstruction of evolutionary history, and even stratigraphic correlations. Modern taxonomy and systematics of extant cockroaches requires an integrative study involving multiple lines of evidence with emphasis on genital and reproductive characteristics and molecular data. In contrast, many fossil cockroach taxa published recently are based solely on forewings. Many studies have shown that forewing-based taxa are questionable. In order to find out how much of the phylogenetic signal we could ascertain from venational similarity, and how confident we could be, this study used forewing characters to reconstruct phylogenies of the genera of well-recognized family-group taxa. The intuitively reconstructed phylogeny of 75 extant genera failed to recover those taxa or their relationships. Parsimony analyses of various datasets all yielded strong polyphyly and chaotic relationships. In conclusion, the forewing of cockroaches is not a universally competent character system. The underlying causes are the complicated nature of veins and the limitations of current analytical techniques. The uncertainty in forewing-based taxonomy and systematics has been underestimated in the literature. Forewing-based fossil taxa warrant re-evaluation; some of them are herein deemed nomina dubia in their current state. [ABSTRACT FROM AUTHOR]

The rich micromammal fossils from Early, Middle, and Late Miocene horizons of the Damiao sequence in Nei Mongol provide an opportunity to study Miocene biostratigraphy and faunal turnover in Asia. In this study, we describe thirteen dipodid species from the Damiao sequence, including two new species, Sinozapus damiaoensis sp. nov. and Lophocricetus parvus sp. nov. Sinozapus damiaoensis sp. nov. is characterized by the metaloph connecting to the central hypocone on M1-M2, the absence of the anterior arm of the protoconid, and the posterior arm of the protoconid merging with the metaconid on m2. Lophocricetus parvus sp. nov. displays a set of transitional morphological traits between Heterosminthus and Lophocricetus. It resembles Heterosminthus in its small size, the presence of the mesocone and mesoloph on M1-M2, the vestigial pseudomesolophid, and the posterior crest of the protoconid on m1. Meanwhile, it has the characteristics of Lophocricetus, including the protostyle on M1 and the hypoconid-entoconid connection on the m1. These two new species represent the earliest records of their respective genera. The Damiao dipodid fossil records improve our understanding of Neogene dipodid diversity, and refine the biostratigraphic framework in the central Nei Mongol. The new fossil records reveal a shift from small, low-crowned, humid-adapted early taxa to ecologically diverse late Middle Miocene forms, including desert-adapted jerboas, indicating a trend towards regional aridification. Nonetheless, relict sicistines and zapodines suggest localized persistence of humid refugia within broader dry environments during the late Middle Miocene, which sheltered pliopithecids in the Mongolia Plateau. [ABSTRACT FROM AUTHOR]

Cuttings and logs from four boreholes in the Mediterranean Sea, offshore the northwestern side of the Nile Delta, Egypt (30°00'–30°24' N, 31°18'–31°30' E), were examined lithostratigraphically, biostratigraphically and paleoenvironmentally. Five planktonic foraminiferal zones were determined assigning the studied boreholes to be late Miocene-Early Pliocene in age. These zones are Globorotalia mediteraneaneana Zone Sphaeroidinellopsis seminulina Zone, Globorotalia margaritae margaritae Zone, Globorotalia puncticulata Zone and Globorotalia inflate. Studying benthonic foraminifera indicated a general shallowing upward trend in all boreholes and tracking the distribution of the foraminiferal assemblages by counting the total number of foraminifera and planktic/benthic ratios provide a history of the progression of deltaic facies with secondary cycles of sea-level change. [ABSTRACT FROM AUTHOR]

The studied wells were located in the Bandar Abbas, Southeast Persian Gulf, and crosscut mainly from Eocene to Oligocene sequences spanning the Pabdeh, Jahrum, and Asmari formations respectively. The present work aims to characterize the biostratigraphy of the Eocene–Oligocene transition based on planktic and benthic foraminifera. Upper Eocene–Oligocene transition are subdivided into three lithostratigraphic units which are the Pabdeh Formation (Priabonian–Chattian), Jahrum Formation (Priabonian), and Asmari Formation (Rupelian-Chattian). Based on the stratigraphical range of the studied foraminifera, ten biozones have been established:- Morozovella velascoensis Zone (early Eocene) (I), Morozovella edgari Zone (Ypressian) (II(, Morozovella formosa formosa Zone (Ypressian) (III), Hantkenina alabamensis Highest-Occurrence Zone (Priabonian) (IV), Turborotalia cerroazulensis cunialensis Zone (Priabonian) (V), Cassigerinella chiploensis–Pseudohastigerina micra) Zone (Rupelian) (VI), Turborotalia ampliapertura Zone (Rupelian) (VII), Praegloborotalia opima opima Zone (Rupelian) (VIII), Nummulites spp., Discocyclina spp. Zone (Chattian) (IX) and Eulepidina–Nephrolepidina-Nummulites Zone (Chattian) (X). The recognized biozones were correlated with comparatively standards biozones for the Tethyan realm which demonstrates a good comparison between the biostratigraphic zones that recognized in this study with other biozones in different areas. [ABSTRACT FROM AUTHOR]

This is the second of a two-part New Zealand Journal of Geology and Geophysics Special Issue on understanding sedimentary systems in Aotearoa-New Zealand's Hikurangi Subduction Margin (HSM). This volume includes six research papers that explore sediment-tectonic interactions operating over a range of spatio-temporal scales. We take a distinctive perspective moving from the subduction deformation front in the Hikurangi Trough, upslope to the subduction wedge, and onshore to the Coastal Ranges. Temporally, papers span the onset of subduction in the Miocene, to disentangling provenance of turbidity currents triggered by the 2016 CE Kaikōura Earthquake. Collectively, the studies in the special issue reveal a complicated and continually evolving margin, where active tectonics and volcanism, coupled with vigorous climatic and oceanographic drivers, modulate erosion, transport, and depositional cycles of vast volumes of terrigenous sediment into ocean basins. Despite decades of significant research advances in our knowledge of the HSM, considerable scope remains for future work. A deeper understanding of fundamental tectonic-sediment interactions operating on active margins, along with the significant geohazards they pose remain outstanding research needs. Collectively, Volumes 1 and 2 highlight enduring interest in the HSM as a globally important natural laboratory for the study of subduction zone geoscience. [ABSTRACT FROM AUTHOR]

A deep-marine sedimentary succession of Whaingaroan to Altonian age (Early Oligocene–Early Miocene), cropping out near Weber, southern Hawke's Bay, records abrupt changes in depositional paleoenvironments and sedimentary lithofacies. Highly calcareous early Waitakian (latest Oligocene) Weber Formation (Mangatu Group/Waka Supergroup) is unconformably overlain by terrigenous-dominated late Waitakian–Otaian (Early Miocene) Coast Road or Whakataki formations (Tolaga Group/Māui Supergroup). Most notably, in some localities, lowermost parts of the Coast Road Formation (Mangapuku Mudstone Member) contain prominent matrix-supported extra-formational olistoliths of centimetre to decametre scale derived from the underlying Weber Formation. Deposition of these blocks is attributed to deep-water collapse of parts of rapidly growing, over-steepened, reverse-fault-controlled thrust ridge(s). The onset of Coast Road and Whakataki formation deposition and associated abrupt changes in sedimentary lithofacies correlate to prominent Early Miocene lithological, mineralogical, and paleoenvironmental changes elsewhere along the Hikurangi Margin. We attribute these bio- and lithostratigraphic changes as evidence for significant shortening and upper-plate reverse faulting marking the onset of subduction beneath eastern North Island during the mid-Waitakian (c. 23 Ma). Proposed lithostratigraphic revisions presented herein help clarify depositional events and correlative sedimentary packages within the Miocene Hikurangi margin. [ABSTRACT FROM AUTHOR]

New biostratigraphically constrained chronologies have been developed to help elucidate the sedimentary and tectonic history of Quaternary sequences on the Hikurangi margin of north-eastern Zealandia. Three sites on the mid to lower slope of the accretionary prism (IODP Site 372-U1517, 375-U1519, 375-U1518) and two sites east of the deformation front (Hikurangi Trough Site 375-U1520 and Tūranganui Seamount Site 375-U1526) are dated using a detailed biostratigraphic framework based on planktic foraminiferal records from ODP Site 181-1123. The dating indicates sedimentation rates are very high and variable on the accretionary prism (0.2–9.6 m/kyr), especially during the Last Glacial Maximum (LGM) when downslope redeposition from the continental shelf and upper slope is common. Sedimentation rates at Hikurangi Trough Site 375-U1520 are also variable (0.01–3.0 m/kyr) and they increase markedly as the incoming site approached the deformation front, especially during the LGM, due to an abundance of downslope redeposition from the inner to mid shelf. The incoming Quaternary section at Tūranganui Seamount Site 375-U1526, is punctuated by hiatuses that shorten in duration as the site approached the deformation front, whilst sedimentation rates remain relatively low (0.04–0.4 m/kyr). [ABSTRACT FROM AUTHOR]

Zealandia has very few biostratigraphic markers to help elucidate the often complex and discontinuously cored stratigraphy of Quaternary sequences on the margins and submarine plateaux of the subcontinent. In this study, a detailed biostratigraphic framework has been developed to help unravel the complex stratigraphy of tectonically deformed Quaternary sediments on the Hikurangi margin of north-eastern Zealandia. The framework is based on well documented and dated 0–1.2 Ma planktic foraminiferal records from Ocean Drilling Project (ODP) Site 181–1123 on the Chatham Rise, just north of the Subtropical Frontal Zone. The framework has 104 biostratigraphic markers and is subdivided using the Sinistral Truncorotalia truncatulinoides Zone (STZ) 0–533 ka, the Dextral Tr. truncatulinoides Zone (DTZ) 533–2440 ka, the lowest common occurrence (LCO) Tr. truncatulinoides (621 ka), the highest common occurrence (HCO) Neogloboquadrina pachyderma (624 ka), and the HCO Tr. crassacarina (1101 ka). Further subdivision is then based on the tops and bases of short-lived climatically-tempered influxes of Globigerinoides ruber, Hirsutella hirsuta, Hr. praehirsuta, Tr. truncatulinoides, Tr. crassacarina, and Nq. pachyderma. Most of these biostratigraphic markers are not unique, but sequences of markers that are unique to each marine isotope stage provide an unprecedented level of biostratigraphic detail and chronological dating when they are used within the contextual chronological framework of keystone biostratigraphic markers. [ABSTRACT FROM AUTHOR]

In the revised ammonoid biostratigraphy of Becker (1993), the base of the German Hemberg-Stufe (Hembergian, middle Famennian, Upper Devonian III) was defined by the entry of Pernoceras dorsatum (Wedekind, 1918). However, this taxon is an invalid junior homonym of Tornoceras simplex var. dorsata Gürich, 1900 and Wedekind's form was poorly defined and originally not illustrated. Based on a review of Wedekind material and unpublished collections from two trenches at the Enkeberg type section, the defining taxon of the Hembergian is re-assigned to Protornoceras genulobatum (Sobolew, 1914b). The species is discussed in the context of previous records of Tornoceras dorsatum and in the taxonomic framework of the Aulatornoceratinae, especially of the genera Protornoceras and Pernoceras. In the revised regional and international zonation scheme, UD III-A becomes a regional Prot. genulobatum Zone and international Protornoceras Genozone. Some other Protornoceras, questionable Falcitornoceras, and Pernoceras are described. These include Prot. rhenicum n. sp., Prot. umbilicatoides (Sobolew, 1914a), Prot. aff. delepinei (Petter, 1975), and Prot. aff. crebriseptum (Raymond, 1909) from the Enkeberg, Prot. aff. genulobatum from Beringhauser Tunnel, the Rhenish Perno. kochi (Wedekind, 1908), and the Russian Pernoceras kirsaense n. sp. [ABSTRACT FROM AUTHOR]

A 200 m thick drill core penetrating the Givetian Hahnstätten Reef in the southwestern Lahn Syncline (Rhenish Massif) was investigated. A range of different depositional environments is described based on lithofacies and microfacies analysis. All in all, nine lithofacies types (FTs) are distinguished, which can include subfacies types. The majority of lithofacies of these ultrapure carbonates is represented by lime mudstone and fenestral microbialites, all pointing to shallow subtidal, intertidal to even supratidal low-energy palaeoenvironments. In contrast, more high-energy parts of the reef were dominated by bioclastic rubble deposits (e.g. rudstone). Autochthonous, reef-building carbonates are represented by bafflestone and framestone. Diversity of reef building organisms (stromatoporoids and corals) is low and is dominated by Stachyodes, Actinostroma, Stromatopora, and Thamnopora and alveolitids, respectively. Other bioclasts are brachiopods, gastropods, ostracods, foraminifera, echinoderms, trilobites, and conodonts in descending order. Development of the Hahnstätten Reef is interpreted as having been controlled mainly by synsedimentary tectonics and volcanism with contributions from eustasy. The occurrence of Stringocephalus burtini in the entire section and conodont findings, which provide more precise biostratigraphic data confirm an early to middle Givetian age (Polygnathus rhenanus/varcus Zone to Polygnathus ansatus Zone) of the succession. The average quality of the ultrapure carbonates lies at 97.68% CaO (excl. loss of ignition), with 70% of the core ranging between 98% and 99% CaO. This extremely high purity makes it difficult to identify correlations between lithofacies and geochemical data. [ABSTRACT FROM AUTHOR]

In the Baltic States and Belarus, the Middle Devonian period is characterised by an abundant fossil record of invertebrates such as scolecodonts, brachiopods, ostracods, trilobites, bivalves, crinoids, gastropods, and tentaculites. On the other hand, there was limited diversity in the conodont and other vertebrate fauna. In this study, we introduce a newly refined ichthyofaunal assemblage from the Eifelian and Givetian epochs from the present-day regions of Belarus and Lithuania. The isolated scales of Cheirolepis are identified as C. gaugeri, C. cf. gaugeri, C. aleshkai, C. cf. aleshkai, and Cheirolepis sp., while Orvikuina is represented by the isolated scales of O. vardiaensis and Orvikuina sp. The histological analyses for the scales of Orvikuina are provided here. Moreover, Orvikuina and Cheirolepis taxa are now recognised to be widely distributed throughout the Baltic States, especially Lithuania and Belarus, as a result of these findings. Thus, this ichthyofaunal data markedly improved the biostratigraphic correlation within the study region and expanded the paleogeographic distribution of these taxa during the Eifelian and Givetian time in Laurasia. [ABSTRACT FROM AUTHOR]

Graptolites represent one of the most important index fossils for the lower to middle Paleozoic biostratigraphy worldwide. Compared to other regions, graptolite faunas exhibited a marked decrease in diversity in Argentina during the Silurian, what resulted in reduced and low-varied registers and denied biostratigraphic works in its territory. This study introduces new Silurian graptolite faunas from the Los Espejos Formation, Poblete Norte section, Central Precordillera of Argentina. A total of thirteen graptolitic levels were identified, containing Bohemograptus bohemicus, Lobograptus sp., Saetograptus argentinus argentinus, Saetograptus cf. S. varians, Uncinatograptus uncinatus notouncinatus, Uncinatograptus elsae sp. nov., and Uncinatograptus lisandroi sp. nov. The occurrence of Uncinatograptus spp. in association with B. bohemicus could indicate the presence of the lower Gorstian Neodiversograptus nilssoni Biozone. A few meters above, the finding of S. a. argentinus in association with S. cf. S. varians, U. u. notouncinatus, and Lobograptus sp. suggest the presence of the lower Gorstian Lobograptus progenitor Biozone. The upper graptolitic beds yield specimens of S. a. argentinus and B. bohemicus, suggesting late Gorstian to early Ludfordian ages. These new graptolite faunas allow to correlate more precisely with local (Precordillera and Famatina), regional (North Western Argentina and Bolivia) and global equivalent sections. This discovery introduces new graptolite faunas, first-time recorded in South America, proposes for the first time a graptolite biostratigraphy for the Ludlow of Precordillera, and complements so far insufficient knowledge on Ludlovian graptolitic faunas of the continent in a critical time in the history of this fossil group.

The first calcareous nannoplankton extinction and recovery close to the Triassic/Jurassic boundary (TJB) were studied in two Tatra Mountains sections of Kardolína and Furkaska. The studied sediments were deposited in an intra-shelf depression of the Tethyan shelf (the Zliechov Basin). Rare nannofossil assemblages were discovered in both sections. Rhaetian nannofossils are characterized by the dominance of Prinsiosphaera triassica and by episodic increases in the abundance of small-sized coccoliths. Coccoliths belonging to Calyculus? kardolinae sp. nov. were found on tops of the bedding planes. Triassic index species Eoconusphaera aff. hallstattensis was also recovered, it is rare though, probably due to the marginal or relatively high-latitudinal position of the area. The uppermost Triassic is characterized by a significant reduction in nannofossil abundance accompanied by the presence of organic matter in the rock, which was significant especially in the Kardolína section. The signal of the last occurrence of Prinsiosphaera triassica is overwritten by the reworking of Upper Triassic material into Jurassic strata within the boundary clay interval. The presence of representatives of Watznaueriaceae in the Jurassic Kopieniec Formation is surprising and might indicate hiatus in the TJB in the studied sections. We are also presenting the results of a newly developed method for the extraction of calcareous nannofossils from indurated rocks.

The paper presents detailed biostratigraphical division and lithological characteristics of the Turonian-Lower Santonian interval within the compiled Chukhonastovka section. The presence of the Lower Turonian deposits has been ascertained alongside with the unusual structure of the rock interval synchronous to the Lower Santonian “sponge” horizon.

The distribution of radiolarians in core LV76-9-1 (southeastern part of the Sea of Okhotsk) is studied. Based on a developed age model of the core, we established the biostratigraphic levels of some key radiolarian species and correlated them with the central part of the Sea of Okhotsk. Changes in the qualitative and quantitative characteristics of radiolarians are recorded during marine isotope stages 5–1. The species Lychnocanoma sakaii Morley et Nigrini, 1995, Cycladophora davisiana Ehrenberg, 1861, and Cerathospyris borealis Bailey, 1856, which are predominant in the Sea of Okhotsk, are divided into morphological forms, and the concentrations of these forms in deposits over the past 122 kyr are established. [ABSTRACT FROM AUTHOR]

The impact of environmental change is intensively studied in the marine realm, whereby only few studies focus on continental sediment archives. Precise correlation of marine and continental sediment archives is complicated, but essential to understand early Toarcian environmental dynamics. The early Toarcian global warming was accompanied by broad volcanism, major marine transgression, and oxygen deficiency in the ocean. The environmental change impacted marine and continental ecosystems. Correlation of marine and continental sections from Western Siberia is based on coeval changes in the microfauna, palynomorphs, and macroflora during the early Toarcian. In Kuznetsk, Kansk, and Irkutsk continental coal-bearing basins of the Siberian realm, the stratigraphic position of the early Toarcian climatic optimum is debated. Thermophilic palynomorphs from palynozone 6 do not correlate with macroflora composition, which does not reflect environmental changes. The Toarcian warming is well expressed in palynomorph assemblages, but not in the macroflora. However, the general evolutionary trends of the Siberian groups of spore plants and gymnosperms (Coniopteris, Ginkgoales, and Leptostrobales) allow us to correlate the palynological and palaeobotanical assemblages from the Prisayan Formation of the Irkutsk Basin to the stratigraphic scheme of Western Siberia. This study may be useful for interregional correlations between the Jurassic continental deposits of the Irkutsk, Kuznetsk, and Kansk basins. [ABSTRACT FROM AUTHOR]

This is the second part of the paper on the Cretaceous of the Mountainous Crimea. A lot of new data has been received during last ten years. This paper summarizes the state of knowledge of the Upper Cretaceous stratigraphy, selected biostratigraphic groups (ammonites, belemnites, ostracods, foraminifers, gilianelles, nannoplankton) and magnetostratigraphy. Ammonite and belemnite biostratigraphic subdivisions are proposed for the first time for the Crimean Upper Cretaceous. Foraminifera-based biostratigraphy is updated, and new biostratigraphic units are proposed and correlated with the European scale. Stratigraphic hiatuses are recognised in the succession of southwestern Crimea: the base and the top of lower Cenomanian, upper Coniacian–lower Santonian, Campanian/Maastrichtian and Cretaceous/Paleogene boundary intervals. [ABSTRACT FROM AUTHOR]

The history of study of the Upper Jurassic Volgian Stage and Lower Cretaceous Ryazanian Stage, their geographic occurrence, and use in world practice, subdivision, and correlation are considered. The data on the occurrence of various groups of macro- and microfossils (ammonites, bivalves, radiolarians, dinocysts, and marine vertebrates) in the Volgian and Ryazanian are reviewed. In spite of significantly different lifestyle of all these groups, the Volgian and Ryazanian assemblages are highly similar in the entire Panboreal Superrealm, on one hand, and significantly different from coeval Tethyan fauna, on the other hand. The biostratigraphic scales of these stages based on successions of ammonites, bivalves, radiolarians, and dinocysts are analyzed. It is shown that the substage boundaries of the Volgian are reliably traced along the entire Panboreal Superrealm. None of the boundaries, except for the base of the Volgian, corresponds even to a zonal boundary of the Tethys–Pantalassa Superrealm. A similar situation is also observed in the Ryazanian: its lower boundary, as well as the Lower–Upper Ryazanian boundary, does not coincide with any well-traced boundary in the Tethys–Pantalassa Superrealm. The necessity of using the Volgian and Ryazanian in geological studies is substantiated for all Russian regions with abundant Boreal deposits, as well as inclusion of these stages to the General Stratigraphic Scale in parallel with the Tithonian and Berriasian. We suggest the cancellation of the Decree of the Interdepartmental Stratigraphic Committee of Russia about the transition of the Volgian into regional stratigraphic subdivisions, as well as the reconsideration of the correlation scheme of the Volgian and Ryazanian accepted in the same decree. [ABSTRACT FROM AUTHOR]

New paleontological and biostratigraphic data were obtained for a series of Middle Ordovician sections in the Charysh-Inya and Uimen'-Lebed' structural-facial zones (SFZ) of the Gorny Altai. Regional stratigraphic stages, namely, the Kuibyshevo and Kostinsky horizons, are discussed in detail. By graptolites, the complete stratigraphic volume of the Kuibyshevo regional unit is defined as following zonal succession: (1) sinodentatus/Cardiograptus/Oncograptus, sinodentatus, (2) austrodentatus, (3) dentatus; and the Kostinsky regional unit within the lentus/balhaschensis/kirgisicus Zone. Beds with conodonts Eoplacognathus pseudoplanus were distinguished in the Batun Section of the Kostinsky Horizon; the same-age beds with conodonts Semiacontiodus asymmetricus–Parapanderodus striatus were distinguished in the Baraniy-1 Section. For the first time in the Voskresenka Formation, in the stratotype of the Kuibyshevo Horizon (Maralikha Section), a brachiopod assemblage was found and identified. [ABSTRACT FROM AUTHOR]

[Display omitted] • First multi-proxy chronostratigraphy of lower Cambrian Byrd Group. • Biostratigraphy demonstrates Cambrian Stages 3–4 age, supported by new ID-TIMS date. • MICE and Sinsk δ13C chemostratigraphic events in upper Shackleton Limestone. Antarctica and Australia were sutured together at the equator during the major pulse of animal biodiversification associated with the Cambrian radiation. However, the lack of detailed systematic chemostratigraphic and biostratigraphic sampling of lower Cambrian sedimentary successions from Antarctica has significantly impeded precise age determination and correlation with Cambrian strata on other palaeocontinents. This study is the first to present integrated, simultaneously sampled biostratigraphic and chemostratigraphic (δ13C isotopes) data from the same measured stratigraphic sections through the lower Cambrian Byrd Group in the Transantarctic Mountains. Shelly fossil assemblages (brachiopods, tommotiids, molluscs, bradoriids, trilobites) from the Holyoake Range and Churchill Mountains facilitate direct correlation with the Dailyatia odyssei Zone of South Australia (Cambrian Stages 3–4), and trilobites provide strong correlation between the Starshot Formation and the Cymbric Vale Formation in western New South Wales. A new ID-TIMS radiometric date of 514.96 ± 0.16 Ma from a tuff in the lower Cymbric Vale Formation is similar to dates from tuff beds in the Third Plain Creek Member of the Mernmerna Formation in the Flinders Ranges, providing an important absolute-age tie point between these lower Cambrian successions. Chemostratigraphic data from the upper Shackleton Limestone in the Holyoake Range capture a negative δ13C excursion that can be correlated to negative values within the multi-peaked MICE (cycles V–VIII in Siberia). Integrated faunal and chemostratigraphic data indicate a Cambrian Stages 3–4 age, giving robust chronostratigraphic context for the upper Shackleton Limestone–Holyoake Formation–Starshot Formation succession for the first time, permitting reconstruction of the depositional history of the lower Cambrian of Antarctica and global correlation of Byrd Group strata. [ABSTRACT FROM AUTHOR]

This paper discusses Early Bajocian Leptosphinctes found for the first time in the interfluve of the Kuban and Urup rivers (Karachay-Cherkessia). A microconch of L. (Kubanoceras) bolshensis sp. nov. is described. Fragments of macroconch shells recovered from the same concretion containing the holotype of the new species were identified as L. (Leptosphinctes) cf. garnieri Pavia; the holotype of this species comes from the Lower Bajocian Blagdeni Subzone of the Humphriesianum Zone in France. The new data are important for understanding the initial stage of the evolution of the family Perisphinctidae. [ABSTRACT FROM AUTHOR]

Microorganisms have inhabited the oceans since the dawn of Earth. Some of them have organic walls and some produce mineral tests that are usually composed of carbonate minerals or silica. They can therefore be preserved with original parts during sedimentary deposition or fossilized through permineralization or carbonization processes. The most common marine fossil groups studied by micropaleontologists are cyanobacteria, coccolithophores, dinoflagellates, diatoms, silicoflagellates, radiolarians, foraminifers, red and green algae, ostracods, and pteropods. Dormant or reproductive cysts can also be used for determinations of the fossil microbiota. Microfossils can be studied in petrographic slides prepared from rocks or separated from loosely consolidated rocks by disaggregation or dissolution and wet sieving. Their presence is sometimes recognized by biomarkers. Transmitted light microscopy and reflected light stereomicroscopy are necessary for micropaleontological studies whereas scanning electronic microscopy (SEM) aids research on the tiniest fossils and reveals fine skeletal details. Microorganisms have influenced the oxygenation of water and the atmosphere, as well as Earth's carbon cycle and have contributed to the formation of sedimentary rocks. By studying microfossils, paleontologists depict the age of the rock and identify depositional environments. Such studies help us recognize periods of stress in Earth's history and understand their influence on living organisms. Biogenic rocks, made of microfossils, can be used as raw materials, such as fossil fuels, building stone, or additives for the food industry, agricultural, or cosmetic purposes.

A reliable character system is crucial to taxonomy and systematics, and it promises valid downstream inferences, e.g., estimates of diversity and disparity, reconstruction of evolutionary history, and even stratigraphic correlations. Modern taxonomy and systematics of extant cockroaches requires an integrative study involving multiple lines of evidence with emphasis on genital and reproductive characteristics and molecular data. In contrast, many fossil cockroach taxa published recently are based solely on forewings. Many studies have shown that forewing-based taxa are questionable. In order to find out how much of the phylogenetic signal we could ascertain from venational similarity, and how confident we could be, this study used forewing characters to reconstruct phylogenies of the genera of well-recognized family-group taxa. The intuitively reconstructed phylogeny of 75 extant genera failed to recover those taxa or their relationships. Parsimony analyses of various datasets all yielded strong polyphyly and chaotic relationships. In conclusion, the forewing of cockroaches is not a universally competent character system. The underlying causes are the complicated nature of veins and the limitations of current analytical techniques. The uncertainty in forewing-based taxonomy and systematics has been underestimated in the literature. Forewing-based fossil taxa warrant re-evaluation; some of them are herein deemed nomina dubia in their current state.

Abstract: In order to study the Qom Formation, the ostracodes of members c1 to c4 and e of this formation were studied in the south Shurab section. The studied strata in this section have a significant abundance and diversity of ostracods. Changes in the abundance and diversity of species in the ostracodes of the studied members show that Member c2 was deposited in a shallower environment compared to the middle and upper part and the base of Member c3. The high abundance of psychrophilic species at the base of Member c4 and the presence of thermophilic forms at the top of Member c4 indicate that the basin was deeper at the time of deposition of the base Member c4 sediments than at its top. Also, the visible changes in the ostracods collection in marly Member e indicate frequent fluctuations in the depth of the environment during the deposition of this member in the studied area. In general, it can be inferred that the environment of members c1 to c4 and e of the Qom Formation was a warm with moderate salinity sea water. In the biostratigraphic studies, 42 species belonging to 36 genera of ostracoda and four biozones have been identified. Based on the biostratigraphic studies, the Chattian age was determined for the sediments of the top of Member b and c1, the Aquitanian for the sediments of members c2 to c4, and the Burdigalian for the sediments of Member e of the Qom Formation in the Shurab section was determined. Keywords: Qom Formation, Ostracoda, South of Shurab, Biostratigraphy, Palaeoecology Introduction The Qom Formation is a significant geological unit due to its hydrocarbon resources, making it a focus of geological studies. This formation in its extensive area in central Iran, within the Sanandaj-Sirjan and Urumieh-Dokhtar zones exhibits remarkable changes both laterally and vertically, making it a subject of geological interest both in terms of surface outcrops and subsurface sections. Diverse fossil contents and significant facies changes have prompted stratigraphic researchers to investigate the Qom Formation based on its available fossil contents, in order to understand more about this formation, and also solve existing problems and ambiguities , and complete its study chain. In this regard, one of the fossil groups with significant diversity and abundance in the Qom Formation is the ostracods, which has received less attention and few studies have been conducted on it. The significance of studying the Qom Formation from one side and the importance of ostracodes as a useful tool in paleontological studies, particularly for determining the age of different parts of the Qom Formation and identifying its palaeoenvironment, on the other hand, has led this research to deal with biostratigraphic and palaeoecological studies of members c1 to c4 and e of the Qom Formation in the south Shurab section, located southeast of Qom based on ostracod findings in the area. Material & Methods In this study, research was conducted in two phases: fieldwork and laboratory work (sample preparation and ostracod identification using a stereomicroscope). A total of 255 samples were collected and examined from members c1 to c4 and e of the Shurab section. Sample preparation by washing method included the use of 35, 70, 80, and 120 mesh sieves. Separation of ostracods from the sediments was performed using a stereomicroscope, which led to the identification of 2685 ostracodes, including 42 species belonging to 36 genera from 12 families and two suborders. After identifying the ostracodes, their range chart was drawn, and then, - the ages of members c1 to c4 and e of the Qom Formation in the Shurab section were determined along with their biostratigraphic zones.. In the palaeoecology study, counting and statistical analysis of ostracod species was done so that the number of species present in each sample was identified separately and the percentage of abundance of each species in relation to the total identified ostracodes was calculated. Finally, the palaeoenvironment of the studied members of the Qom Formation in the south of the Shurab section was predicted based on ostracodes. Discussion of Results & Conclusions The Qom Formation with a thickness of 544 meters is outcropped in the Shurab stratigraphic section located in the southeast of Qom. In this section, members c1, c2, c3, c4, and e respectively with thicknesses of 30, 113.5, 13 and 19 meters, and Member e with a thickness of 49.8 meters were subjected to biostratigraphic and palaeoecological studies. Based on the identification of 2685 ostracodes obtained from 255 samples from the mentioned members, while recognizing 42 species belonging to 36 genera from two suborders in the Podocopida order, the following 4 biozones are identified and introduced. assemblage zone Cyamocytheridea reversa -4- Cytherella vulgate assemblage zone Cytheridea Josephina-3- Neonecidea gerda 2- Quadrocytheris symmetric- Actinocythereis rosefieldensis assemblage zone 1-Cytheretta (Flexus) trifurcate - Cytherella obesa assemblage zone Among the mentioned biozones, biozone 1 belongs to the top of Member b, biozones 2 and 3 belong to members c2 to c4, and biozone 4 belongs to Member e. In Member c1, due to the presence of dense limestone facies and the impossibility of separating ostracodes, the biozones were not introduced. On the basis of the identified biozones and the ostracodes available there, the Aquitanian age for members c2 to c4, and the Burdigalian for Member e is suggested. For sediments at the top of Member b, based on its existing ostracodes, and for Member c1 based on its stratigraphic position and regional studies, the age of the Chattian was determined. Palaeoecological studies of the existing ostracodes in the upper sediments of the members b to e, significant changes in abundance and diversity are seen under the influence of changes in depth, temperature and salinity. These changes show that the environment of the formation of the above-mentioned members had significant fluctuations in depth, so that the presence of thermophilic genera belonging to shallow areas, such as Actinocythereis, at the top of Member b and the base of Member c2. The genera belonging to deeper areas, such as Cytheropteron, in the middle to the end of Member c2 and the marl base of Member c3, indicate the changes in depth from the shallow depth at the top of Member b and the base of Member c2 to a greater depth in the middle part of c2 to the base of c3. This deepening is also evident at the base of Member c4, so that psychrophilic genera such as Cytherella, Krithe and Paracypris have a significant abundance in this part, while towards the top of Member c4, the abundance of psychrophilic genera decreases and thermophilic genera belonging to shallower environments, such as Pontocypris, Actinocythereis, Propontocypris, increase and generally show a shallowing towards the top of this member. In Member e, the changes in the abundance and diversity of ostracodes indicate fluctuations in the water depth at the time of the formation of this member, so that at the beginning of Member e, the abundance of thermophilic species indicates the establishment of a shallow environment in the continuation of the evaporative environment of Member d. But this gradually upwards with the increase of the abundance of psychrophilic genera such as Krithe, Cytherella, and Paracypris, and the environment has became deeper. Similarly, in the second half of Member e, as the the depth decreased, thermophilic species initially increased, and finally as the depth increased, psychrophilic species became more abundant. The ostracodes identified in the studied members show that the most abundant during the deposition of the mentioned succession belonged to thermophilic species. Also, the salinity studies show that the most abundant of species in the aforementioned members belong to the species related to the marine environment with normal salinity.

Abstract This paper contributes to an understanding of the tectono‐sedimentary evolution of the South Pyrenean foreland system by reviewing the chronostratigraphic framework of the basin infill in its eastern sector. Six sections are analysed and cross‐correlated to build a 6.5 km thick composite magnetostratigraphy that represents the complete record of the Cadí Nappe in the Ripoll Syncline. New and previous magnetostratigraphic sections are integrated with available biostratigraphy to provide a new age calibration of the sedimentary succession of the Cadí Nappe, encompassing from Palaeocene to Middle Lutetian age. The proposed correlation with the Geomagnetic Polarity Time Scale aims at best reconcile magnetostratigraphic data with the regional biochronology built on the marine Shallow Benthic Zonation (SBZ biozones), the continental mammalian biochronology (MP levels) and the newly collected charophyte data. A subsidence analysis was performed on the calibrated composite succession, resulting in two well‐defined intervals bounded by a hiatus. A Palaeocene to Early Eocene interval with low (11–21 cm/kyr) total subsidence rates, and an Early to Middle Eocene interval, characterised by high (70–75 cm/kyr) total subsidence rates. The detailed trends in both subsidence and sedimentation mark the development and evolution of the foreland depozones, from distal foreland depozones to foredeep and wedge‐top depozones, relative to the emplacement of the Pedraforca Nappe and Cadí Thrust Nappe. The most pronounced sedimentary shift in the Cadí Nappe occurred at 49 Ma, with the rapid drowning of the carbonate platforms and its transition into talus and deep basinal environments. Carbonate platforms collapsed and resedimented on the talus of the elongated trough, newly formed parallel to the orogenic front. This marked the onset of tectonic subsidence triggered by the submarine emplacement of the Lower Pedraforca Nappe. The emersion of the orogenic wedge drove the entry of siliciclastics, lagged by 1 Myr, into the Ripoll Trough. The foredeep filled rapidly (5.5 km thickness in less than 7 Myr) compared to other South Pyrenean regions, favoured by its semi‐enclosed palaeogeography. The emplacement of the Vallfogona Thrust as early as the Middle Lutetian (43 Ma) brought the Cadi Nappe into a wedge‐top setting. However, the Ripoll growth syncline continued acting as a temporary sink for alluvial sedimentation while a foredeep developed further south in the autochthonous Ebro Basin. The flexural response of the Iberian plate to the tectonic thickening of the Axial Zone counterbalanced for a period the local uplift of the Cadi Nappe, providing accommodation space for the top sediments filling the Ripoll Syncline.

Species diff erentiation within the genus Mesorbitolina Schroeder 1962 is primarily based on the general structure of the megalospheric embryo and its biometrics. The taxonomy of three taxa, namely Mesorbitolina texana (Roemer 1849), Mesorbitolina subconcava (Leymerie 1878) and Mesorbitolina pervia (Douglass 1960) is complicated due to diff ering species concepts between authors, and, in the case of the fi rst two named, by missing type designations in the original descriptions as well as disagreements with respect to their type-localities. Herein, it is demonstrated that M. pervia is the junior synonym of Mesorbitolina birmanica (Sahni 1937) due to priority reasons, both taxa characterized by a similar-sized plano-convex protoconch. Some concepts of M. texana and M. subconcava can also be placed in M. birmanica, but not those as defi ned by lectotypes. Published data for M. birmanica suggest a late Aptian (late Gargasian) to early (? late) Albian age and a cosmopolitan distribution. Mesorbitolina texana appears slightly earlier in the late Aptian persisting into the middle Albian, and a distribution ranging from the southern USA to the Middle East. [ABSTRACT FROM AUTHOR]

Microfaunal analysis of Cretaceous and Paleogene sediments collected over several decades from Western Siberia has illuminated the diversity, stratigraphic distribution, and paleoecological signifi cance of the rare low trochospiral benthic foraminiferal genus Bagginoides. Here, we describe two new species B. yamalensis n.sp. and B. tibeisalinella n.sp [ABSTRACT FROM AUTHOR]

The results of a palynological study of the middle Eocene-lowermost Oligocene strata of the Shagap and Landzhar outcrop sections (southern Armenia) are presented. A series of stratigraphically important dinoflagellate cyst events were recognized in the uppermost Lutetian-lowermost Rupelian parts of the sections, including the lowermost occurrences of the key-species Rhombodinium draco, Schematophora speciosa, Hemiplacophora semilunifera, Hapsocysta kysingensis, Thalassiphora? cf. rota, Rhombodinium porosum, Glaphyrocysta semitecta, Reticulatosphaera actinocoronata, Stoveracysta ornata-group and Wetzeliella gochtii. Based on the first-order calibrations with calcareous nannoplankton and foraminifers, R. draco first occurs at the Lutetian-Bartonian transition, while the lowermost occurrence of R. actinocoronata is very close to the Bartonian-Priabonian boundary. The analysis of the ratios of palynogroups and dinoflagellate eco-groups permits to interpret the environmental conditions during the accumulation of regional formations: (1) a major marine transgression started at the beginning of the Lutetian and the gradual deepening of the marine basin occurred during the middle-late Lutetian (Arpa Formation); (2) the marine transgression, accompanied by deepening, continued during the early Bartonian, but towards the end of the Bartonian slightly shallower depositional conditions were established (Azatek Formation); (3) the sea continued to gradually become shallower during the Priabonian (Urtsadzor Formation) and, finally, the maximum of regression was observed at the Eocene-Oligocene transition, ending with the establishment of brackish environments at the beginning of Rupelian (Shagap Formation). [ABSTRACT FROM AUTHOR]

The Neogene-Quaternary continental deposits cover large areas of Greece and several fossil mammal sites have been discovered in the country. There are several collections of large fossil mammals for this time span, which provide important data for the fauna biochronology, correlations, palaeoecology and palaeogeography of the area. The last lists with the fauna, age and biochronology of the Greek large mammal localities were given in 2006 for the Neogene and in 2001 for the Quaternary. Extensive research over the last twenty years provided several new localities, and many data and information were published. Therefore, an updating of the lists was more than necessary, and the present article deals with it; it covers the time span untill June 2023. Lists include all faunal information as the systematic classification, chronology, biostratigraphic correlation of the faunas, and main bibliography. It is worth mentioning that some of the Greek localities are key-localities for the Eastern Mediterranean region, e.g., Pikermi, Axios Valley, Villafranchian collection. These faunas are important for the comparison and identification of new collections, correlations, palaeoecology, and palaeogeography of Neogene European mammals. [ABSTRACT FROM AUTHOR]

This paper presents the first contribution to the study of bryozoans from the Frasnian–lower Famennian successions of Armenia. The latter were examined in two distinct localities (Ertych and Noravank) of Central Armenia; abundant fragments of branched ramose and encrusting bryozoans were observed in them, belonging to the orders Trepostomata and Cryptostomata. Their taxonomic assessment led us to recognize four species: two cryptostomes – Euthyrhombopora tenuis Ernst et al., 2017 and Bigeyella indigena (Morozova and Weiss in Morozova et al., 2002) from the Noravank section (Frasnian) – and two trepostomes – Eostenopora sp. and Eridotrypella sp. from the Ertych section (lower Famennian). No cystoporate and fenestrate bryozoans were observed. The identified bryozoans are characteristic of shallow marine or middle shelf paleoenvironments. The presence of Euthyrhombopora tenuis and Bigeyella indigena suggests palaeobiogeographic affinities to contemporary faunas from Iran and Poland, respectively. In addition to our results, an overview of previously published data reveals that the upper Famennian assemblages of bryozoans from the Lesser Caucasus contain more endemic species than those known from the Frasnian and the lowermost Famennian. [ABSTRACT FROM AUTHOR]

Nannofossils and planktonic foraminifers from the Lower Miocene Alkun Formation of central and western Ciscaucasia were studied in the following sections: the stratotype section on the Alkunka River, the Republic of Ingushetia; stratotype of the Caucasian Regional Stage on the Kuban River, Karachay-Cherkessia; Lower Miocene reference section on the Belaya River, Adygea; and in the sections of the Alkun Formation stratotype area on the Fiagdon and Mairamadag rivers, North Ossetia. Planktonic foraminifers in the Alkun Formation were studied for the first time. The available results made it possible to reveal the composition and structure of nannofossil and planktonic foraminiferal assemblages from the Alkun sediments in Ciscaucasia, to refine their stratigraphic and correlation potential and to recognize bionomic conditions of the Alkun basin in the studied area. As a result of the nannoplankton study the Cyclicargolithus floridanus Beds were recognized in the Alkun Formation and, taking into account the occurrence of the zonal species Triquetrorhabdulus carinatus along with Tr. milowii, they are correlated with the upper (Miocene) part of the Aquitanian Zone NN1. Planktonic foraminiferal data permitted to recognize the Streptochilus pristinum Beds. [ABSTRACT FROM AUTHOR]

Molasses of foredeeps are important indicators of the newest orogenic uplifts, as well as the source of data on climate and landscape changes. One of the fullest sections of Neogene–Quaternary deposits is studied in valleys of the Belaya, Pshekha, and Psekups rivers at the junction of the Western and Northwestern Caucasus with the Eastern Kuban and Western Kuban foredeeps. The formation of the deposits corresponds to the main evolution stages of the Great Caucasus orogen, as well as the foredeeps. A summary of extensive published and original tectonostratigraphic materials has shown that the lowland and then hilly relief in an axial zone of Western Caucasus existed at least from the Middle Miocene. At the same time, the northern flank of the present-day orogen and the foredeeps were located at sea level and were repeatedly flooded by the seas up to the Kuyalnikian (Piacenzian–Gelasian) time, and the Western Kuban Foredeep was flooded even later. The main data on stratigraphy of the upper molasses and Pliocene–Quaternary tectonic movements of the region are based on facies analysis and bio- and magnetostratigraphic studies of the Upper Pliocene–Lower Pleistocene Belorechensk Formation. Its sedimentation started at the beginning of the Kuyalnikian as a result of an increase in the energy of mountain rivers due to the uplift of the riverheads. It is stated that the minimum average rate of uplift of the Western Caucasus in the basin of the Belaya River is 0.8 mm/year over last 4 mln years with acceleration up to 1.7 mm/year from the beginning of the Calabrian. The Belorechensk Formation includes three subformations, which successively become coarser clastic and correspond to the main stages of the accumulation of upper molasses in the Late Pliocene and Early Pleistocene during the intensification of uplifts and landscape-climate changes of Western Caucasus and Ciscaucasia. [ABSTRACT FROM AUTHOR]