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For oil and gas reservoir characterization, permeability prediction is indispensable because it helps identify potential flow pathways and lowers risk. Estimating permeability in heterogeneous media is challenging due to the limited number of measurement tools, low-resolution sampling methods, and sampling bias. To combat these issues, we employed a probe permeameter to produce a high-resolution (4 in [10 cm] spacing) permeability dataset for cores from the Strawn Formation, Katz Field, Permian Basin, Texas, USA. We structured our sampling to record permeability changes related to facies variability and fluctuating bioturbation intensity. We compared probe permeameter data to wireline logs and core-plug porosity and permeability data recorded at larger spacings. The results show that permeability is affected by facies type, bioturbation intensity, and cementation. The effects of bioturbation are non-linear; in our study, moderate bioturbation enhances permeability by improving connections between sands while intense bioturbation decreases permeability by redistributing fines. Core-plug and probe measurements gave similar permeability values, but the number of core plugs taken in the finer-grained intervals was insufficient. The probe, however, provided better resolution and gave larger net-to-gross sand ratios than core-plug-based evaluations. Using only the core-plug porosity–permeability relationship with wireline density log porosities led to permeability predictions too large by a factor of three or more compared to averaged probe permeameter values. [ABSTRACT FROM AUTHOR]

Copyright of Spanish Journal of Palaeontology is the property of Socieadad Espanola de Paleontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The coiled nautiloid Tainoceras luxaeterna sp. nov. is described from the late Kasimovian or early Gzhelian (Late Pennsylvanian) Avilovka Formation in the Donets Basin (Ukraine). It is the first Late Pennsylvanian cephalopod record in Ukraine. The new species is one of the stratigraphically oldest representatives of the genus. [ABSTRACT FROM AUTHOR]

The depositional environment, hydrology and vegetational history of the Lower Radnice Coal (Duckmantian) in the Kladno coalfield was studied using sedimentary geology, coal petrology and paleobotanical/palynological methods. The peat accumulating wetland of the coal formed in a fluvial paleovalley approximately 15 km long and 2–5 km wide, bordered by basement paleohighs and landlocked in the interior of the central European Variscides. The peat swamp evolved on top of mud-dominated floodplain successions pedogenically modified to a vertic gleyed Protosol. Probably climatically controlled rising ground water table resulted in paludification that from downstream part gradually spread upstream. Most clastic load was deposited in the upper part of the valley, whereas only mud suspension was dispersed downstream throughout the vegetated swamp. The best conditions for peat accumulation were situated in the eastern part of the paleovalley, where up to 1.5 m thick coal with thin bands of impure coal and carbonaceous mudstone formed in an occasionally inundated rheotrophic system with peat accretion controlled by regional ground water table. The peat swamp was vegetated mainly by lepidodendrid lycopsids with Lepidodendron and Paralycopodites being dominant genera. Shrubby to ground cover vegetation was represented by medulosallean pteridosperms, small shrubby lycopsids, sphenopsids, and herbaceous ferns. Tree ferns were locally abundant, especially in mineral-rich substrates. The rheotrophic character of the peat swamp may indicate higher seasonality of the Variscan interior, compared to coastal areas in the North Variscan foreland with contemporaneous ombrotrophic peats. Modern equivalents of the Lower Radnice Coal swamp are inland planar tropical peat swamps in tributary paleovalleys of the Tasek Bera in peninsular Malaysia and central Congo basins. Lower Radnice Coal peat swamp. [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]

From the late Carboniferous to the early Permian, multiple pulses of glaciation and deglaciation have been caused by the LPIA. The Pennsylvanian period experienced phases of recovery, proliferation, and decline, ultimately forming a reef system distinctly different from that of the Mississippian period. During the late Bashkirian to Moscovian, the metazoan reef experienced a limited resurgence, with reef predominantly formed by chaetetid developing in the United States, northern China, and Japan. During the Kasimovian to Gzhelian, the phylloid algal reef dominated the global reef systems. In the late Pennsylvanian, bioconstruction cases and paleoenvironmental proxies in southern Guizhou Province were studied to investigate the composition, recovery, and evolutionary processes of the bioconstructions as well as their response to environmental variations during this period. Several bioconstructions have been reported in the Lumazhai section of Houchang Town, Guizhou Province, southern China, from the Moscovian to the Gzhelian. The upper Carboniferous strata are well-preserved and continuously exposed. The continuous strata, abundant fossils, and diverse bioconstructions provide excellent research materials for exploring the mutual constraints between organisms and their environment. This study identified ten microfacies, whose vertical evolution indicated significant changes in the depositional environment related to relative sea-level fluctuations. Skeletal grains are widely present in these facies. Among them, foraminifera, algae, bryozoans, crinoids, and Tubiphytes are the most common and exhibit distinct distribution characteristics in various environments. Quantitative statistics, CCA and theoretical ecospace have been utilized to examine and interpret environmental impact factors. Quantitative analysis of their relative abundance and distribution patterns provides insights into the complex interactions between organisms and environmental factors. The relative abundances of different organisms and factors controlling their bioconstructions are influenced by relative sea-level changes. CCA analysis reveal that hydrodynamic conditions are the primary influencing factor. Variation trends in average tiering and motility reveal the characteristics of biological communities during environmental changes in phylloid algae and microbial bioconstructions. These bioconstructions are not directly correlated with changes in environmental factors, and the biological communities in phylloid algae mounds and biostromes exhibit similar organism compositions and ecological niches across different environments. [ABSTRACT FROM AUTHOR]

Until the late 20th century, the idea of identifying wildfires in deep time was not generally accepted. One of the basic problems was the fact that charcoal-like wood fragments, so often found in sedimentary rocks and in coals, were termed fusain and, in addition, many researchers could not envision wildfires in peat-forming systems. The advent of Scanning Electron Microscopy and studies on modern charcoals and fossil fusains demonstrated beyond doubt that wildfire residues may be recognized in rocks dating back to at least 350 million years. Increasing numbers of studies on modern and fossil charcoal assemblages from the 1970s through the 1990s established the potential importance of wildfires in the fossil record, using Carboniferous examples in particular. Since the 1990s, extensive progress has been made in understanding modern wildfires and their byproducts. New techniques to study ancient charcoals have allowed considerable progress to be made to integrate modern and ancient fire studies, both before and after the evolution of mankind. Four important developments have made a reassessment of Carboniferous wildfires necessary: the recognition of the role of atmospheric oxygen in controlling the occurrence of wildfire; the development of new microscopical techniques allowing more detailed anatomical data to be obtained from charcoal; the integration of molecular studies with the evolution of fire traits; and new developments in or understanding of post-fire erosion/deposition systems. [ABSTRACT FROM AUTHOR]

The ichnogenus Circulichnis Vyalov is a horizontal a ring- or ellipse-shaped burrow and/or locomotion trace of an unknown producer, most likely an annelid or a “worm”, preserved on the bedding plane. This ichnogenus is known over a wide age interval (Ediacaran–Oligocene). Circulichnis demonstrates a wide ecological range and has been found in continental (Mermia ichnofacies), shelf, and relatively deep-water (turbidites) deposits. It is commonly interpreted as a sediment feeding trace, but the peculiarities of its formation remain somewhat mysterious, as it is unclear how the tracemaker reached the sediment surface, as lateral branches of the ring-shaped traces are extremely rare and have only been observed by a few researchers. A rather large specimen of Circulichnis montanus Vyalov, 1971 with a preserved lateral branch was found in the Mospyne Formation (upper Bashkirian, Lower Pennsylvanian) of the Donets Basin. This discovery confirmed the assumption made by Alfred Uchman and Bruno Ratazzi regarding the peculiarities of formation of Circulichnis. According to these authors, a single ring-shaped Circulichnis indicates an attempt to forage at a specific level in the sediment, while the lateral branches of Circulichnis are part of a vertical shaft leading to another level within the sediment. The study of Circulichnis montanus from the Donets Basin has confirmed that at least variant C of the Circulichnis formation scheme proposed by Uchman and Ratazzi is correct, i.e. the lateral branch is a horizontal or subhorizontal part of a generally vertical shaft. However, it is important to note that the correctness of variants A and B of the Uchman and Ratazzi scheme cannot be excluded. To answer this question unequivocally, new finds of well-preserved Circulichnis are necessary.

This paper describes the in situ spores of the Calamospora type, macerated from sixty-one specimens of calamitean cones belonging to sixteen species of genera, such as the Palaeostachya, Macrostachya, Calamostachys, and Huttonia from the Pennsylvanian Czech Republic period, specifically from the Moscovian/Kasimovian ages (i.e., Duckmantian-Stephanian). The in situ spores were compared to twenty dispersed species of Calamospora. The majority of spores were microspores; however, some cones yielded both micro- and megaspores. Morphological variations of the in situ spores, including the diameter, labrum, contact area, ontogenetic stages, and secondary folds of the exine, are described, including their importance for the classification of calamospores. The relationships of Elaterites, Pteroretis, Vestispora, and some monopseudosaccate spores are discussed. All Paleozoic Calamospora-producing parent plants are summarized. [ABSTRACT FROM AUTHOR]

A diverse assemblage of fish microremains is reported from the Virgilian (Gzhelian), Upper Pennsylvanian Finis Shale outcrop at Lost Creek Lake near Jacksboro (Texas, USA). The assemblage contains diverse remains of chondrichthyans, rare acanthodians and actinopterygians. The chondrichthyans are represented by a xenacanthimorph, ctenacanthiforms, symmoriiforms, an euselachian, a neoselachian, a petalodontiform, eugeneodontiforms, a helodontiform and euchondrocephalian taxa. The teeth of Bransonella dominate the chondrichthyan microremains. The occurrence of Bransonella lingulata in the Gzhelian Finis Shales of Texas is the youngest in the world. The assemblage includes widely distributed taxa of chondrichthyans. The chondrichthyan fauna from the Finis Shale outcrop differs from the rich faunas of the Kasimovian–Gzhelian from other regions such as New Mexico and Nebraska in the USA, Moscow, Samara and Volgograd regions of Russia, Spain, Germany and the Czech Republic by the dominance of bransonelliform remains and the set of diverse ctenacanthiforms and euchondrocephalians. The new assemblage of fishes demonstrates the presence of chondrichthyan taxa with different food specialisation in the Virgilian faunal community. [ABSTRACT FROM AUTHOR]

Remains of the Carboniferous graptolites ?Ptiograptus sp. and Dictyonema sp. are described from the Donets Basin and the border zone of the Dnipro-Donets Depression and Donets Basin (eastern Ukraine). These graptolites were found in the Mezhova (Visean, Mississippian) and Avilovka (Kasimovian, Pennsylvanian) formations. Dictyonema sp. from the Avilovka Formation is probably the youngest dendroid graptolite to date. The analysis of geological data allowed to make a reasonable assumption about the Late Devonian rather than the Carboniferous age of the graptolite fauna from the Englewood Formation of South Dakota (USA) and the Tournaisian rather than the Cisuralian age of graptolites from Hainan Island in China. [ABSTRACT FROM AUTHOR]

Sinusoidal trace fossils Cochlichnus anguineus are described for the first time from marine and continental siltstones and sandstones of the Mospyne and Smolyanynivka formations (late Bashkirian, Early Pennsylvanian) in Luhansk Oblast, eastern Ukraine (central Donets Basin). Previously, in Ukraine, Cochlichnus anguineus was recorded in the early Bashkirian Buzhanka Formation of the Lviv Paleozoic Trough. Cochlichnus isp. is known from the Ediacaran of western Ukraine. The studied ichnofossils come from four localities representing sedimentary sequences of shallow marine, lagoonal, and lacustrine terrigenous rocks. The ichnogenus Cochlichnus Hitchcock, 1858 is known from the Precambrian to Holocene and were generally distributed in non-marine environments in the Carboniferous, although it has been recorded in a wide range of environments, from lacustrine (Mermia Ichnofacies) to marine (Cruziana Ichnofacies). In the Pennsylvanian deposits of eastern Ukraine, these trace fossils are predominantly found in lacustrine black shales, but also in lagoonal siltstones and shallow marine sandstones and siltstones. Cochlichnus has been interpreted as traces of grazing, feeding, and locomotion, and it is suggested that traces, depending on the environmental conditions and potential producers, may be combinations of all these ethological categories. Potential producers of Cochlichnus include worms sensu lato, as well as nematodes, annelids, insect larvae, or cyclostomates. In modern freshwater basins, traces morphologically similar to Cochlichnus are produced by nematodes and dipteran larvae. It seems that nematodes and/or annelids are the most likely producers of the studied Cochlichnus, since representatives of Diptera are not known in the Carboniferous. In the Donets Basin, Cochlichnus anguineus usually co-occurs with the trace fossils Lockeia, Planolites, and Palaeophycus. Sometimes these ichnofossils are found on the layer surfaces bearing microbially induced sedimentary structures together with Taphrhelminthopsis and Aulichnites.

Palaeozoic fossils of whip scorpions (Arachnida: Uropygi: Thelyphonida) are extremely rare, with only seven species of this age previously described. A new species of fossil whip scorpion, as well as the first ichnospecies assignable to this group, are described here from the Carboniferous Narragansett Basin of Massachusetts, USA. A body fossil from the Rhode Island Formation (Moscovian) is referred to as Parilisthelyphonus bryantae gen. nov. sp. nov.. At more than 34 mm long it represents both the largest known Palaeozoic whip scorpion and the first fossil arachnid found in the Rhode Island Formation in ~130 years of scrutiny. The whip scorpion trace fossil, comprising a full-body impression and associated tracks, is described from the subjacent Wamsutta Formation (Late Bashkirian) of Massachusetts, USA as I nmontibusichnus charleshenryturneri igen. nov. isp. nov.. With an estimated body length of less than 10 mm, the producer would be the smallest known Palaeozoic thelyphonid. These discoveries within the Narragansett Basin represent only the second site in the western hemisphere, in what was western Laurasia, to yield Palaeozoic whip scorpions. The Narragansett Basin is of significant Pangaean biogeographical importance among whip scorpion sites, being located between the westernmost Mazon Creek Lagerstätte of Illinois and the eastern assemblage of localities in Europe, and serves as an important new fossil calibration point for phylogenetic studies of this arachnid group. [ABSTRACT FROM AUTHOR]

Copyright of Geologija (0016-7789) is the property of Geological Survey of Slovenia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Endophytic feeding behaviors, including stem borings and galling, have been observed in the fossil record from as early as the Devonian and involve the consumption of a variety of plant (and fungal) tissues. Historically, the exploitation of internal stem tissues through galling has been well documented as emerging during the Pennsylvanian (c. 323–299 million years ago (Ma)), replaced during the Permian by galling of foliar tissues. However, leaf mining, a foliar endophytic behavior that today is exhibited exclusively by members of the four hyperdiverse holometabolous insect orders, has been more sparsely documented, with confirmed examples dating back only to the Early Triassic (c. 252–250 Ma).Here, we describe a trace fossil on seed‐fern foliage from the Rhode Island Formation of Massachusetts, USA, representing the earliest indication of a general, endophytic type of feeding damage and dating from the Middle Pennsylvanian (c. 312 Ma).Although lacking the full features of Mesozoic leaf mines, this specimen provides evidence of how endophytic mining behavior may have originated.It sheds light on the evolutionary transition to true foliar endophagy, contributes to our understanding of the behaviors of early holometabolous insects, and enhances our knowledge of macroevolutionary patterns of plant–insect interactions. [ABSTRACT FROM AUTHOR]

The Carboniferous outcrops from Adarouch (central Morocco) are composed of siliciclastic and carbonate rocks, and the latter have yielded abundant fossils. The upper part of the marine succession in the Idmarrach Formation and its laterally equivalent Tirhela Formation belong to the Bashkirian. More recent investigations of poorly preserved coral assemblages from the upper part of Idmarrach 2 section and the upper part of the Tirhela Formation are here described. The assemblage from the upper Idmarrach Formation comprises several typical Mississippian taxa, such as Aulophyllum fungites, Dibunophyllum bipartitum, Koninckophyllum interruptum, Siphonodendron scaleberense and Lithostrotion decipiens, and some highly evolved forms previously undescribed of Mississippian genera such as Haplolasma sp., Arachnolasma sp., Siphonodendron sp., Diphyphyllum sp., Solenodendron sp., Clisiophyllum sp. and a new species Corwenia tirhelensis sp. nov. In addition, an undetermined petalaxid has been also recorded. Similarly, the assemblage from near the top of the Tirhela Formation yielded some species regarded usually as Mississippian, such as Palaeosmilia murchisoni and Lithostrotion decipiens. We also identified the long-ranging tabulate Syringopora sp., Corwenia tirhelensis sp. nov., and a single species of the fasciculate rugosan, Siphonodendron tindoufense, previously described from Bashkirian rocks in the Tindouf Basin (southern Morocco). The presence of the latter taxon in both the Idmarrach and Tirhela sections implies a communication between the Adarouch region and the Saharan basins. The occurrence of S. tindoufense at the approximately same stratigraphic level in Tindouf, Taoudenni, Reggan-Ahnet and Adarouch, demonstrates its important regional stratigraphic value in North Africa. [ABSTRACT FROM AUTHOR]

Phyllosilicates are hypothesized to be primarily of pedogenic origin in shallowly buried paleosols (≤3 km depth), regardless of the age of the paleosol. To test this hypothesis, this work evaluates the possible presence of detrital and diagenetic phyllosilicates in middle and upper Pennsylvanian paleosols, collected from three drill cores along a north–south transect in the Illinois Basin. The abundances of 2M1 muscovite, quartz, and K-feldspar are greater in a morphologically immature Protosol from the southernmost core; 1Md illite and interstratified illite-smectite with R1 and R0 stacking orders are more abundant in the more mature Vertisols of the central and northern cores. K-Ar age values of multiple clay-size fractions from each paleosol averaged ~260 Ma in the northern core, 270 Ma in the central core, and 295 Ma in the southern core. While considering the complex tectonic and thermal history of the Illinois Basin, detrital minerals are more abundant in immature paleosols that experienced relatively greater maximum burial depths and thus greater sediment supply whereas illitization in more mature paleosols was probably initiated primarily during protracted burial diagenesis. As the present study found evidence for diagenetic and detrital minerals in clay-size fractions of shallowly buried, deep-time paleosols, caution is advised when using paleosol minerals for ancient climate and environment reconstructions. [ABSTRACT FROM AUTHOR]

An extensive sample of well-preserved conulariids from the Pennsylvanian of the North American Midcontinent (Texas and Oklahoma, USA) have been studied using X-ray micro-Computed Tomography (µCT) and have shown structures identified as longitudinal muscle bundles and a potential gastric cavity. These unequivocal structures appear in several specimens coming from different sites. Their preservation varies from a gastric cavity with muscle bundles in some individuals to only longitudinal muscle bundles in others. The muscle bundles fuse apically or medially, normally forming V-shaped pairs, and they extend along the theca/exoskeleton, parallel to the corner, towards the aperture. Longitudinal bundles have predominant perradial positions. Although there have been some articles on conulariid soft parts, most of them refer to relic soft parts. This is the first time that these structures are shown using µCT. Discovery of conulariid soft parts contributes to knowledge of metazoan evolutionary history. [ABSTRACT FROM AUTHOR]

A vertical sequence of brachiopods was revealed at the base of the Verkhoyanian terrigenous complex of the Tit-Ary section in the northern part of the Tuora-Sis uplift of the lower reaches of the Lena River. As a result of the study of these brachiopods, it was established that in the indicated section, the Upper Cambrian dolomites are overlain by Gzhelian and Asselian deposits, characterized by brachiopods of the Jakutoproductus protoverkhoyanicus and Jakutoproductus verkhoyanicus biostratigraphic zones. This is the first proven fact of the presence of Upper Carboniferous deposits in the area. It is concluded that within the Tuora-Sis uplift from south to north, the upper age limit of the unconformity between the Cambrian and the Upper Paleozoic is growing older, while the base of the Verkhoyanian terrigenous complex is built up by the Permian basal beds and the Gzhelian deposits of the Upper Pennsylvanian. The Tit-Ary section is the first of those established in the lower reaches of the Lena River, with exposed boundary Carboniferous–Permian beds. [ABSTRACT FROM AUTHOR]

Analysis of fusulinids from the Bug Scuffle Limestone Member of the Gobbler Formation along the western escarpment of the Sacramento Mountains in south-central NewMexico demonstrates that all four Desmoinesian regional fusulinid zones documented in Midcontinent and Southwest North America are present in the stratigraphic unit. Earliest Desmoinesian (Df1 Zone) fusulinids from the basal Bug Scuffle limestone beds suggest that the carbonate unit transgressed northward on the Sacramento Shelf, with Beedeina insolita in basal beds of the southernmost canyon exposures, and the slightly more advanced B. hayensis and B. curta in basal limestone beds of more northern outcrops. Late early Desmoinesian (Df2 Zone) fusulinids are common and widespread throughout the escarpment outcrop belt indicating that it was the time period with the most widespread normal marine shelf paleoenvironmental conditions. The diverse assemblage of the Df2 Zone is characterized by Beedeina novamexicana, B. euryteines, B. leei, B. socorroensis, B. joyitaensis, Wedekindellina euthysepta, and W. excentrica. The microprobematical branching fossil Komia is also common in this zone. Wedekindellina and Komia do not range above the mid-Desmoinesian CSB1 composite sequence boundary. Above that sequence boundary, the early late Desmoinesian Df3 Zone is characterized by sparse Beedeina haworthi, and the closely related B. illinoisensis and B. tumida. The late late Desmoinesian Df4 Zone is represented by a diverse assemblage of fusulinids in the uppermost part of the Bug Scuffle Limestone Member in the southern canyon exposures, including Beedeina acme, B. megista, B. mysticensis, B. lonsdalenesis, B. bellatula, B. gordonensis, and B. vintonensis. No Beedeina identifiable to species were found in upper part of the Bug Scuffle Limestone Member in the northernmost canyon exposures, demonstrating that late Desmoinesian paleoenvironments became more restricted marine northward along the Sacramento Shelf. Above the CSB2 composite sequence boundary in the uppermost Bug Scuffle Limestone Member, the lower part of the uppermost depositional sequence continues to contain latestDesmoinesianDf4 Zone fusulinids in the southern canyon sections. EarlyMissourian conodonts have been reported in a limestone unit near the top of the Gobbler clastic detritalmember in the north-central part of the outcrop belt(Wahlman and Barrick 2018; Lucas et al. 2021), but no early Missourian conodonts or fusulinids have been reported yet from the uppermost Bug Scuffle Limestone Member in the southern canyons. [ABSTRACT FROM AUTHOR]

The new ichnotaxon Bromleyia magnifica n. igen., n. isp., attributed to the feeding activity of bivalves, is proposed. This ichnotaxon consists of clusters of closely spaced curved ridges that form a fan-shaped structure oppositely distributed on both sides of a longitudinal axis or, more rarely, being present only on one side. Intergradation between Protovirgularia, Lockeia, and Bromleyia forms a compound trace fossil that records the activity of a cleft-foot protobranch bivalve while burrowing, moving through the sediment, and stopping to deposit feed. A specimen from the Carboniferous of Arkansas, previously regarded as Lophoctenium isp., is here included in Bromleyia magnifica. The spreite in Lophoctenium reflects complex behavioural patterns of horizontal strip-mining deposit feeders, including bundles of tubes bending to one side in a pectinate way or arranged on both sides in a highly systematic fashion, which contrasts with the coarse, horizontal fan-shaped, curved bundle of ridges from the Arkansas specimen. The trace fossil Hillichnus lobosensis records the activities of tellinacean deposit feeders and displays feather-like spreite structures reminiscent of Bromleyia. However, the spreite in Hillichnus is more organized, recording repetitive probing through the sediment in horizontal, oblique, and vertical directions of the tubular inhalant siphon. The resulting complex feeding structure, recorded in multiple preservational tiers, displays an alternate arrangement of ridges on either side of an axial basal structure. This configuration differs from the mostly horizontal, less-organized, coarse bundle of ridges with broadly opposite distribution to the sides of an axis present in Bromleyia. Moreover, contrary to Hillichnus, Bromleyia is commonly associated with Lockeia, indicating significant differences in burrowing strategy and mode of construction between these two ichnotaxa. [ABSTRACT FROM AUTHOR]

Late Paleozoic (Variscan) magmatism is widespread in Central Europe. One of the critical areas that contributes to the understanding of the complex volcanotectonic processes at the Pennsylvanian to Cisuralian transition is the Chemnitz- Flöha Volcanic Zone (CFVZ). The latter is part of the type region of the Saxo-Thuringian Zone of the European Variscides. For the Altenhain Rhyolite, which is part of the CFVZ we present a complete dataset concerning its whole-rock geochemistry. The potassium-rich Altenhain Rhyolite originated from a highly differentiated, calc-alkaline, peraluminous, A-type granitic melt with an intra-plate signature. There are strong geochemical similarities to the Flöha Ignimbrite and the Zeisigwald Tuff pyroclastics, both belonging to the CFVZ. The occurrence of a rare mineral from the arsenogoyazite/arsenoflorencite-(Ce) solid solution series is recognised. [ABSTRACT FROM AUTHOR]

U-Pb isotope ages from magmatic zircon grains are provided for different volcanic rocks of the NW Saxonian Volcanic Basin within the Rochlitz and Wurzen volcanic systems. Measurements were obtained with LA-ICP-MS and revealed late Pennsylvanian to early Cisuralian ages (301-299 Ma). For the Rochlitz Volcanic System supereruption, we present for the first time a radiometric age consistent with biostratigraphic evidence. We report geochemical data for the Gnandstein Andesitoid, the Dölitzsch, Rüdigsdorf, Rochlitz and Wolftitz tuffs and the Rochlitz-α Ignimbrite. The results yield a modified picture of the Kohren, Rochlitz and Oschatz formations as well as new insights into the understanding of the complex volcano-tectonic processes of the NW Saxonian Volcanic Basin, an area of the Saxo-Thuringian Zone of the European Variscides. [ABSTRACT FROM AUTHOR]

Sea anemones (Actiniaria) are among the rarest of recognized fossil organisms, even rarer than jellyfish. Here we demonstrate that the most abundant fossil in the Pennsylvanian Mazon Creek Lagerstätte of Illinois, Essexella asherae, is an infaunal or semi‐infaunal anemone. Essexella is redescribed based on a taphonomic analysis of thousands of specimens, as well as associated medusae and trace fossils. Specimens of Essexella (also known as the 'blobs') were long believed to be medusae, but we reassign Essexella to the order Actiniaria and reinterpret the putative jellyfish Reticulomedusa as the pedal or oral disc of Essexella. We also implicate Essexella as a producer of Conostichus, a widespread plug‐shaped trace fossil that occurs in coeval strata in the same region. Radiate structures comparable to the bases of Conostichus and the ichnofossil Bergaueria, as well as the pedal discs of modern anemones, characterize Reticulomedusa. Bona fide medusae are present in the Mazon Creek biota, and include Anthracomedusa turnbulli and Octomedusa pieckorum, whereas the soft‐bodied fossil Lascoa mesostaurata is referred to Problematica. [ABSTRACT FROM AUTHOR]

Hybrid carbonates, defined as the combinations of in situ abiotic, microbial, and skeletal precipitates, have changed with the biological and environmental conditions throughout geological history. After a long interval of dual-hybrid carbonates, the triple hybrid carbonates became predominant in the late Pennsylvanian and lasted until the Middle Triassic. The organic reefs of the upper Moscovian–Kasimovian (mid–late Pennsylvanian) strata of Guizhou, South China, are composed of abundant microbial carbonates, abiotic marine cements, and skeletal organisms, which are classified as triple hybrid carbonates. Microbial boundstones consisting of aragonitic cements (e.g., botryoidal cements) and microbial micrite are the major contributors to the reefs, as framework constructors, cavity fillers, and hard substrate for the encrusting metazoans. Skeletal components (e.g., the colonial rugose coral Ivanovia) and stromatolitic microbial carbonates could build simple frameworks with the growth cavities filled by syndepositional marine cements, automicrite, and carbonate particulate sediments. In situ phylloid algae normally form patch reefs and biostromes with abundant microbial micrite and peloids, while algal fragments contribute to the skeletal–cement–microbial reefs as large grains encrusted by microbial carbonates or marine cements. Petrographic features suggest the reefs formed at a shelf margin or upper slope setting with active water circulation. The evolution of Carboniferous organic buildups was primarily driven by changes in reef-building organisms, closely linked to external conditions, specifically seawater chemistry and paleoclimate. The ubiquitous triple hybrid carbonates in South China reefs, in agreement with Pennsylvanian tropical shallow-water reefs in their components, are proposed to derive from the interaction between decreasing atmospheric CO2 concentration, high seawater Mg2+/Ca2+ ratio, warm tropical water, and the evolution of skeletal organisms in the Pennsylvanian. [ABSTRACT FROM AUTHOR]

The cyclic to non-cyclic Pennsylvanian-Lower Permian successions of the Robledo Mountains, New Mexico and the Carnic Alps, south Austria, record the acme and demise of the late Palaeozoic ice age (LPIA). Microfacies analyses of cyclic strata of the Pennsylvanian-Asselian Horquilla, Shalem Colony (New Mexico), and Schulterkofel (Carnic Alps) formations record glacioeustatic sea-level fluctuations of an amplitude on the order of 100 m. These fluctuations were the result of Milankovitch-driven eustatic sea-level shifts associated with the waxing and waning of ice sheets during the peak of the main phase of the LPIA. Microfacies analyses of the overlying upper Asselian cyclothems of the Community Pit, Robledo Mountains (New Mexico) and Zweikofel (Carnic Alps) formations record relatively moderate sea-level variations on the order of a few tens of metres (~ 30–40 m). This comparatively minor sea-level amplitude may be linked to the demise of ice sheets during the final stages of the LPIA and the limited input that shrinking ice sheets had on global sea-level fluctuations prior to their final collapse at the Asselian-Sakmarian boundary. The uppermost part of the Robledo Mountains and the Apache Dam (New Mexico) and Zottachkopf (Carnic Alps) formations are Sakmarian. These strata are interpreted as non-cyclic and represent sedimentation following the end of the LPIA. [ABSTRACT FROM AUTHOR]

Simple Summary: Two new representatives of the blattinopsid genus Glaphyrophlebia, from the Gzhelian of Southern France and Spain, respectively, are described and illustrated. They suggest that the diversity of this genus began to increase during the latest Carboniferous, possibly in relation to the climatic changes occurring at that time. Glaphyrophlebia victoiriensis sp. nov. (Paoliida: Blattinopsidae) is the third Gzhelian representative of the genus and is described based on a beautiful forewing from the Var department in Southern France. Together with the description of another forewing fragment of a Glaphyrophlebia sp. from the Province of León in NW Spain, they improve our knowledge of fossil insects from French and Spanish upper Carboniferous deposits. The specimen of Glaphyrophlebia sp. is the first mention of the family in the Carboniferous of Spain and extends the geographical distribution of the genus. These descriptions suggest that the genus Glaphyrophlebia was speciose during the Upper Pennsylvanian, while otherwise very diverse in the lower and middle Permian strata of the Russian Federation. We proposed the first hypothesis to explain the diversification of the family and of its most speciose genera and to argue that their diversity dynamics were likely linked with the major environmental changes that followed the collapse of the Carboniferous rainforest, notably the extension of arid biomes during the Permian period. The exquisite preservation and the fineness of the sediment from Tante Victoire, in which the new species was found, suggests that the locality is suitable for preserving other fossil insects and will require additional investigations. [ABSTRACT FROM AUTHOR]

Restudy of Campyloprion annectans Eastman, 1902 from North America demonstrated that neither specimen included is diagnostic at the species level; thus, the species name is a nomen dubium. Since this species was designated as the type species of the genus, this requires suppression of the generic name also. Another species earlier assigned to Campyloprion , Campyloprion ivanovi Karpinsky, 1924 is used as a type for a newly established genus Karpinskiprion Lebedev et Itano gen. nov. The composition of the family Helicoprionidae Karpinsky, 1911 is reviewed, and a new family Helicampodontidae Itano et Lebedev fam. nov. is erected. A new specimen of Karpinskiprion ivanovi (Karpinsky, 1924) recently discovered in the Volgograd Region of Russia is the most complete Karpinskiprion specimen ever found. It unambiguously demonstrates the coiled nature of these tooth whorls and presents information on their developmental stages. During organogeny, cutting blades of the crown became reshaped, and basal spurs progressively elongated, forming a grater. Whorl growth occurred by addition of new crowns to the earlier mineralised base followed by later spur growth. In contrast to consistently uniform cutting blades, spurs are often malformed and bear traces of growth interruption. Both sides of the outer coil of the tooth whorl bear lifetime wear facets. The youngest (lingual) crowns are as yet unaffected by wear. The best-preserved facets show parallel radially directed scratch marks. The upper jaw dentition of Karpinskiprion is unknown, but we suggest that the faceted areas resulted from interaction with the antagonistic dental structures here. Three possible hypotheses for this interaction are suggested: (a) two opposing whorls acted as scissor blades, moving alternately from one side to another; (b) the lower tooth whorl fitted between paired parasymphyseal tooth whorls of the opposing jaw; or (c) the lower tooth whorl fitted into a dental pavement in the upper jaw. [ABSTRACT FROM AUTHOR]

This article discusses the history of the study of the Late Carboniferous-Early Permian genus Somoholites, and changes in views on its taxonomy, species composition and diagnostic characters. Most species of this genus come from Russia. Several species are known from the USA, Canada, Indonesia (Island of Timor), Japan, and probably China. Based on the study of materials from Bashkortostan (Shakhtau quarry), Verkhoyansk Region and the Polar Urals, and published data, the diagnostic characters of the genus are re-evaluated, and its diagnosis and species composition are emended. It is concluded that the South Ural Somoholites described as S. beluensis does not differ significantly from another species from this region S. shikhanensis and should be considered under this name. [ABSTRACT FROM AUTHOR]

The term hardground refers to a surface of synsedimentary lithification associated with non-deposition or slow sedimentation. This paper introduces a marine hardground with characteristic microscopic properties in the Pennsylvanian Atoka bank carbonates, which forms a stratigraphic trap for natural gas. The algal bank complex includes several elongated biostromes up to 21 m thick, oriented normally to the paleo-shelf margin. Several lithofacies have been identified in the bank carbonates and surrounding sediments: crinoidal limestone (grainstone/packstone), nodular shaly limestone (wackestone/mudstone), bank margin (grainstone/boundstone), algal bank (wackestone), brecciated limestone, basal bioclastic micritic pile (wackestone), limy shale, and black shale. Phylloid alga, Archaelithopyllum, is the main fossil component in the bank complex and indicates deposition in a shallow marine environment at depths less than 30 m. The other fossils found with phylloid algae such as bryozoans, brachiopods, and echinoderms (sessile benthic suspension feeders) and small benthic foraminifers point out an open shelf environment away from clastic input. The hardground in the carbonates is characterized by an irregularly eroded surface capping well-lithified peloidal grainstone including scattered phylloidal algal plates and overlain by phylloid algal plates and large brachiopod fragments which are extending subparallel to the bedding surface. When the bank complex during the growth approaches to wave base, that increases agitation in the environment and erosion at the upper surface of the banks. Furthermore, agitation leads to the lithification of the peloidal sediments which decreases from the hardground surface into the sediments. Micro-borings penetrate downward into the lithified sediments. The poorly lithified bioclastic sediments with marine internal lime silts in the sheltered pores just above the hardground surface gradually pass upward into algal wackestone and reflect deepening conditions in the environment. [ABSTRACT FROM AUTHOR]

Concentrations of redox-sensitive trace-element (RSTE) in marine shales have long been interpreted simply as redox proxies. However, the impact of other non-redox factors (e.g., sea-level fluctuation and seawater chemistry) on the enrichment of RSTE, especially molybdenum (Mo) and uranium (U), in sediments has been rarely reported. This study presents newly obtained RSTE datasets from the Upper Pennsylvanian organic-rich Cline Shale in the silled Midland Basin, U.S., to illustrate the influence of sea-level fluctuation on the authigenic accumulation of RSTE in marine sediments. A previously established transgressive-regressive sequence of the Cline Shale, a well-constrained high-amplitude glacio-eustatic fluctuation curve, and an accompanying episodic resupply of aqueous RSTE from the Panthalassic Ocean provide an ideal stratigraphic framework for determining the spatial and temporal variations of sediment RSTE enrichment patterns that responded to the episodic variations of seawater chemistry in this marginal silled paleomarine basin. Results suggest that although slightly higher median RSTE concentrations were observed in sediments from more reducing environments, the overall variation ranges of RSTE concentrations largely overlap among sediments deposited from a wide redox spectrum (from oxic to euxinic conditions) or different sea-level statuses in the Cline Shale. In contrast to the sediment RSTE enrichment patterns, the variations of sediment Mo/TOC and U/TOC ratios are coupled with glacio-eustatic fluctuation. The highest Mo/TOC and U/TOC ratios are commonly observed in sediments deposited during the highest relative sea-level (RSTE resupply), whereas the lowest Mo/TOC and U/TOC ratios usually appear in sediments deposited during the lowest relative sea-level (RSTE depletion). Our findings suggest that the benthic redox conditions recorded in sediment Mo and U concentrations can be greatly obscured and weakened by depleted aqueous Mo and U concentrations in highly restricted basins. Thus, the use of sediment Mo and U concentrations as redox proxies in these highly restricted basins should be tested and calibrated with other redox proxies. [ABSTRACT FROM AUTHOR]

The Olistostrome member of the Sana-Una Paleozoic complex of the Ljubija ore mine in Bosnia and Herzegovina contains limestone fragments of pebble to block size that have been examined paleontologically. The recovered conodont fauna of the first sample is characterized by the species Declinognathodus lateralis, Idiognathoides sulcatus sulcatus and Idiognathodus sp. confirming its mid-Bashkirian age. This report is the first on the occurrence of these taxa in the area. The second sample with chaetetid demosponges yields an abundant diversified microbiota consisting of cyanobacteria, algae and foraminifera. Chlorophyts are marked by the common siphonoclad occurrence of Donezella lutugini and D. lunaensis, whereas rhodophyts include rare representatives of Stacheia, Stacheoides, Pseudoungdarella and Masloviporidium. The presence of Asphaltinella horowitzi and Aphralysia carbonaria of unclear taxonomic position is also documented. Pseudostaffellids, eostaffellids and other foraminifera, mostly endothyrids are present. The examined associations of fossils point to the Bashkirian age of the primary rock that originated in a very shallow habitat most probably linked to a high-energy reef environment.

In central-western Argentina, sedimentological and paleontological studies have identified changes in sea levels during the Pennsylvanian period. After the late Serpukhovian-early Bashkirian postglacial transgression, two main flooding events occurred. Among these, Pennsylvanian transgressions 1 and 2 are considered the most significant. New palynological samples recovered from the T1 transgression in Puesto Volcán, western Precordillera (San Juan province) reveal the presence of the Raistrickia densa-Convolutispora muriornata (DM) Biozone. The palynofloras are characterized by the recognition of Ahrensisporites cristatus , Lundbladispora spp., Raistrickia densa , Spelaeotriletes ybertii , and monosaccate pollen grains. The composition of the assemblages includes some taeniate pollen grains suggesting their assignment to the Subzone B. A new orthoconic cephalopod was also identified in the same stratigraphic interval, which adds to the invertebrate faunal record and confirms the marine environment. Imprints of foliage of Fedekurtzia argentina complete the paleofloristic assemblage. A late Bashkirian-earliest Moscovian age is suggested according to the well constrained radiometric control of the palynostratigraphy in the region. • New palynofloras are described from transgressive deposits in Precordillera. • The assemblages are included in the late Bashkirian-early Moscovian Subzone B. • Associated invertebrates would be related to the Pennsylvanian Transgression 1. • Plant remains are dominated by pinnae of Fedekurtzia argentina. [ABSTRACT FROM AUTHOR]

We follow the wing venation pattern of Schubnel et al. [[12]], and the terminology for wing colouration of Schneider and Werneburg [[13]] adapted to the wing venation terminology. M with MA area branching off approximately in middle the wing; expanded areas between main veins, especially that between M and CuA; wing surface with bright maculae located in costal area and in form fasculae at each wing tip. Schneider et al. [[20]] proposed the following emended diagnosis: 'Phyloblattid-like wing venation pattern but with a much lower number of veins and with extended fields between the main veins. He proposed the following one for I S. hercynica i : 'forewing 16 mm long and 5 mm wide, markings basically like I S. euglyptica i , but the maculae and fasculae are even more extensive, so that the vein seams are more delicately developed; more branches at CuA than I S. euglyptica i '; the following diagnosis for I S. ilfeldensis i : 'approximately 3.2 × 1.13 cm large forewing. [Extracted from the article]

The conodonts of the Moscovian–Kasimovian boundary beds were restudied in the Kalinovo section—one of the most continuous successions in the Donets Basin, eastern Ukraine. Species of Idiognathodus and Swadelina are most common in the studied interval. Swadelina subexcelsa and Idiognathodus sagittalis, two of four species proposed as hypothetical index species for the Moscovian–Kasimovian boundary are registered in the Kalinovo section. I. turbatus and I. heckeli were not identified in the Donets Basin so far. Four conodont zones were distinguished in the studied Moscovian–Kasimovian boundary interval: the Swadelina gurkovaensis, Sw. subexcelsa, Sw. makhlinae and Idiognathodus sagittalis–I. neverovensis zones. Two potential biostratigraphic events were investigated for selection of the lower boundary of the Kasimovian Stage. One of them is defined by the FAD of Swadelina subexcelsa. It coincides with the base of the Krevyakinian Regional Substage, which is the traditional Moscovian–Kasimovian boundary in the type Kasimovian. But in the Donets Basin the Sw. subexcelsa and Sw. makhlinae zones belong to the upper part of the Lomovatkian Regional Stage, which is late Moscovian in age. This contradicts to the correlation by conodont data. The second event is defined by the FOD of Idiognathodus sagittalis and a number of new conodont species recovered close to the base of the Toretzian Regional Stage of the Donets Basin, and described herein shortly in open nomenclature. This event is more prominent in conodont evolution due to occurrence and then dominance of new species of Idiognathodus and extinction of the Swadelina species characteristic of a whole Upper Moscovian Substage. This event corresponds to the Khamovnikian Regional Substage of the Kasimovian type area, one substage higher than the traditional Moscovian–Kasimovian boundary. This event with outburst of new species documents the new step in conodont evolution. If the position of the Moscovian–Kasimovian boundary will be selected by the FAD of one of the three species—I. sagittalis, I. turbatus or I. heckeli, the boundary will be placed in the lower or middle part of the Khamovnikian Regional Substage of the type Kasimovian and at the base of the Toretzian Regiostage in the Donets Basin. At present according to the Ukrainian Carboniferous Stratigraphical Scheme the Moscovian–Kasimovian boundary in the Donets Basin takes place already at the base of the Toretzian Regiostage. Its position is based on the cyclo-stratigraphic analysis. It does not correspond to that in the Kasimovian stratotype. The correlation of the Donets Basin with the Moscow Syneclise, Ural Mountains, North Spain and partly with South China (Tethyan Province) is mostly reliable but correlation to the U.S. Midcontinent is complicated due to presence of mostly endemic species in both Eurasia and North America. The Moscovian–Kasimovian boundary interval is characterized by a sea-level lowstand that isolated marine basins. [ABSTRACT FROM AUTHOR]

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During the late Palaeozoic Era, a series of related marine strata dominated by multi-layer limestones were deposited in the southern North China Craton. In order to gain new insights into the systematic geochemistry of the carbonate succession of the representative formation (Taiyuan Formation), we examined 59 limestone samples collected from the Huaibei Coal Basin (HCB), with a view towards quantitatively determining the major and trace elements and stable isotope compositions. The data obtained can provide essential evidence for reconstruction of the depositional palaeo-environment and tectonic setting of the Taiyuan Formation. Both X-ray diffraction analyses and palaeoredox proxies (e.g. V/Cr, V/(V + Ni) and authigenic U) indicated that the limestone layers were deposited in an oxic–dysoxic zone, with calcite as the main component. Moreover, palaeomagnetic evidence provided support for the conclusion that these limestones were laid down within an epicontinental sea depositional environment under a warm or hot palaeoclimate during the transition between late Carboniferous and early Permian time. Additionally, evidence obtained from our analyses of trace and rare earth elements revealed that the tectonic setting of the Taiyuan Formation (L1–L5) in the HCB transited from an open ocean to a passive continental margin, thereby indicating that this transformation stemmed from the subduction closure of the northeastern Palaeotethys Ocean. The findings of this study would be of interest to those working on the upper Palaeozoic marine strata in the southern North China Craton. [ABSTRACT FROM AUTHOR]

A new genus and species of trigonotarbid (Arachnida: Trigonotarbida) is described from the late Carboniferous (Middle Pennsylvanian, Moscovian) of the Pilsen Basin in the Czech Republic. Doubravatarbus krafti gen. et sp. nov. is assigned to the family Aphantomartidae and is principally diagnosed by its relatively long and gracile legs compared to other trigonotarbids such as for example Eophrynidae and Anthracomartidae. The specimen is preserved in pale grey volcanic ash fall deposits, a type of entombment which is presumably responsible for the instant burial and nearly complete preservation of the trigonotarbid's body. Its possible habitat in the original ecosystem is discussed in relation to the associated flora and its taphonomic implications. [ABSTRACT FROM AUTHOR]

Three new genera Heslerodoides gen. nov., Gzhelodus gen. nov., and Samarodus gen. nov. were erected on the basis of numerous isolated teeth found in the late Carboniferous of European part of Russia. The teeth of the ctenacanthiform Heslerodoides resemble the teeth of Heslerodus and demonstrate the morphological variations of teeth in their dentition. The protacrodontid euselachian Gzhelodus is closely related to Deihim and Tiaraju. The peculiar teeth of Samarodus possess a combination of features previously unknown in the Palaeozoic chondrichthyans. The new taxa contribute to the knowledge of the variety of dentitions in the Carboniferous shark. [ABSTRACT FROM AUTHOR]

Large leafy calamite stems are very rare in the fossil record. One such leafy stem is described as a new species, Calamites cambrensis, from shales above the No 2 Rhondda Seam in the Bolsovian of the South Wales Coalfield.

Pleurotomariida have the longest fossil record among living gastropods and are diverse and abundant in the middle and upper Palaeozoic. Its traditional classification is based on adult shell characters. The early shell morphology has been largely unknown. We describe exceptionally well‐preserved Pleurotomariida from the Pennsylvanian marine shales of Texas, Oklahoma, Kansas and Ohio. In total, 38 species representing 19 genera are described, including 10 new species, one new genus and one new subgenus: Eirlysella buckhornensis gen. et sp. nov., Shansiella (Oklahomaella) globilineata subgen. et sp. nov., Phymatopleura girtyi, Phymatopleura conica, Worthenia (Yochelsonospira) kuesi, Dictyotomaria turrisbabel, Paragoniozona yanceyi, Spiroscala shwedagoniformis, Peruvispira oklahomaensis, Baylea tenera. Replacement names are Paragoniozona ornata nom. nov. (for Pleurotomaria aspera Girty), Spiroscala quasipulchra nom. nov. (for Euconospira pulchra Batten). The early ontogenetic shells including protoconchs and early teleoconchs are reported in detail for the first time for most taxa. Most species have a protoconch of one whorl as that of living Vetigastropoda. Planktotrophic protoconchs (multi‐whorled larval shells with sinusigera) are reported for Platyzona and Peruvispira; they are therefore placed in the family Goniasmatidae (Caenogastropoda). Repaired shell scars were found in juvenile Pleurotomariida specimens (c. 1 mm), suggesting exposure to predation from an early stage of ontogeny. Pleurotomariida are strongly dominant in surface samples of the Finis Shale (Texas) but in bulk samples using fine mesh‐sizes, dominance is much less pronounced, indicating a change in clade proportion depending on sampling method. The taxonomic richness and abundance of Pleurotomariida seen in these Carboniferous shales have not been reported from post‐Triassic formations. [ABSTRACT FROM AUTHOR]

Fossils are useful as palaeoenvironmental indicators when evaluated using large occurrence and lithology association data sets and/or functional morphology. However, when functional morphology is invoked on an ad hoc basis there exists a risk of circular reasoning. Performance spaces/landscapes constructed using biomechanical experiments can be used to tie performance to morphology quantitatively. They can be used to estimate fitness and function in specific environments by allowing multiple specific measures of function to be evaluated simultaneously. Absolute performance can be used to constrain palaeoenvironmental interpretations by detecting functional limits. We constructed a performance space with four variables (transport resistance, settling time, settling orientation and respiration potential) relating to hydrodynamic and metabolic variables. We combine new performance data with existing palaeoenvironmental interpretations and associated distributions of brachiopods of the suborder Productidina during the late Carboniferous and early Permian in the North American Midcontinent. Productidines were chosen because they lacked pedicles and relied on body and spine morphology to interact with their environment. Offshore dysoxia‐associated taxa had increased resistance to sinking and proportionally larger lophophores, potentially improving survivorship in low‐oxygen, soft substrate environments. Taxa associated with nearshore and oxygenated offshore environments display a range in performance consistent with a range of conditions, but all had proportionally smaller lophophores. Models that are less stable in high‐velocity flows consistently settle in the correct convex down orientation if entrained, while more stable models did not. Our study suggests that as productidines radiated during the Carboniferous, they also differentiated within the performance space. [ABSTRACT FROM AUTHOR]

The Early Pennsylvanian land plant community is characterized by widespread forests consisting of lycopsids, ferns, and seeds fern in swampy wetlands. The contemporaneous palynological assemblages are mainly composed of spores of Lycospora spp., Densosporites spp., and Laevigatosporites spp. and monosaccate prepollen of Florinites spp. Taeniate bisaccate pollen appeared for the first time during the Early Pennsylvanian but never prevailed in the coeval palynological assemblages. Here, we report a taeniate bisaccate pollen‐dominated palynological assemblage from the Jiamuhe Formation of Well Ke 85 in the Zhongguai Uplift, northwestern Junggar Basin, Xinjiang. Nineteen miospore species belonging to 14 genera were identified from the assemblage. Based on their relative abundance, one assemblage is nominated informally as Calamospora breviradiata–Lunatisporites tersus (BT) assemblage. SIMS U–Pb geochronological analysis of zircons from two volcanic ash beds from the basal and upper parts of the formation yields weighted mean 206Pb/238U dates of 316.3 ± 2.2 Ma (MSWD = 1.2, n = 19) and 316.5 ± 2.8 Ma (MSWD = 0.85, n = 20) in an ascending order. A Bashkirian age is thus assigned to the BT assemblage. Our combined palynological and geochronological investigations reveal an early stage of the rise of conifers in the Kazakhstan Plate and offer a rare glimpse into the Early Pennsylvanian land vegetation in the subtropical area at the northern hemisphere. [ABSTRACT FROM AUTHOR]

We evaluate the influences of elevation and climate on the spatio-temporal distribution of wetland and dryland biomes during the Pennsylvanian and early Permian in tropical Pangea. The longstanding "upland model" places drought-tolerant vegetation in elevated habitats, where slope and drainage created moisture-limited substrates under a humid climate that simultaneously promoted peat accumulation in contemporaneous lowlands. Upland plants were periodically transported to, and buried in, lowlands. Rare preservation of dryland vegetation thus reflects its general absence in basins, and taphonomic vagaries of long-distance transport. The alternative "climate model" proposes that drought-tolerant plants dominated tropical habitats when climate was seasonally dry, with wetland vegetation reduced to scattered refugia. Environmental changes attending glacial-interglacial cycles caused alternating wetter-drier conditions, and the relative abundance of wetland versus dryland biomes in basinal lowlands thus varied with climatic oscillations. The paucity of drought-tolerant plants reflects a preservational megabias against habitats with seasonal moisture deficits. The environmental signal of "mixed" plant-fossil assemblages, comprising taxa characteristic of both wetland and dryland biomes, may help resolve these debates. We review key Pennsylvanian and lower Permian mixed assemblages from tropical Euramerican Pangea, and interpret their original habitats and climatic contexts based on multidisciplinary lines of evidence, including sedimentology, taphonomy, physiology, and paleoecology. Evaluations also consider patterns of vegetational distribution and taphonomy in modern tropical environments. We suggest that even a cursory view of current tropical plant distribution exposes flaws in the upland model. Where tropical climate is sufficiently humid to support peat swamps, slopes and elevated habitats do not host drought-tolerant vegetation, but are occupied by plants similar to those in lowland settings. This occurs because equable, high precipitation strongly dampens water-table variation across entire landscapes. Furthermore, taphonomic studies indicate that most plant-fossil assemblages record vegetation living near the burial site. Fossil floras thus reflect environmental conditions near their growth site, excluding an upland origin for most occurrences of drought-tolerant taxa. Conversely, the climate model is consistent with modern tropical vegetational distribution and soundly explains late Paleozoic floristic patterns. When Pangean tropical lowlands experienced seasonally dry conditions, plants tolerant of moisture deficits dominated most habitats, whereas wetland vegetation was restricted to wetter sites with greater preservation potential. This occurred because topographic variations are magnified under seasonal precipitation regimes, creating a complex habitat mosaic with wetland patches in a landscape subject to seasonal drought. Accordingly, we propose that a macrofloral assemblage with even rare drought-tolerant taxa indicates seasonality in the broader landscape. At larger spatio-temporal scales, disagreement also persists about whether tectonic uplift or long-term climatic drying was the primary driver of changes in late Paleozoic floristic patterns and areal extent of tropical peat swamps. We argue that tectonic activity alone cannot explain the drastic reduction in peat swamps or coincident changes in dominance-diversity of wetland vegetation. Rates of plant dispersal and evolution far outpace that of mountain building, and peat-forming wetlands persisted in elevated habitats well into the Late Pennsylvanian. Therefore, progressive late Paleozoic aridification was the most probable driver of changing floral patterns and the distribution of wetland and dryland biomes in tropical Pangea. [ABSTRACT FROM AUTHOR]

The Pennsylvanian lowlands of western Pangea are best known for their diverse wetland floras of arborescent and herbaceous ferns, and arborescent horsetails and clubmosses. In apparent juxtaposition, a very different kind of flora, dominated by a xerophilous assemblage of conifers, taeniopterids and peltasperms, is occasionally glimpsed. Once believed to represent upland or extrabasinal floras from well-drained portions of the landscape, these dryland floras more recently have been interpreted as lowland assemblages growing during drier phases of glacial/interglacial cycles. Whether Pennsylvanian dryland and wetland floras were separated spatially or temporally remains an unsettled question, due in large part to taphonomic bias toward preservation of wetland plants. Previous paleobotanical and sedimentological analysis of the Markley Formation of latest Pennsylvanian (Gzhelian) age, from north central Texas, U.S.A, indicates close correlation between lithofacies and distinct dryland and wetland megaflora assemblages. Here we present a detailed analysis one of those localities, a section unusual in containing abundant palynomorphs, from the lower Markley Formation. Paleobotanical, palynological and lithological data from a section thought to represent a single interglacial/glacial phase are integrated and analyzed to create a complex picture of an evolving landscape. Megafloral data from throughout the Markley Formation show that conifer-dominated dryland floras occur exclusively in highly leached kaolinite beds, likely eroded from underlying soils, whereas a mosaic of wetland floras occupy histosols, ultisols, and fluvial overbank deposits. Palynological data largely conform to this pattern but reveal a more complex picture. An assemblage of mixed wetland and dryland palynofloral taxa is interpolated between a dryland assemblage and an overlying histosol containing wetland taxa. In this section, as well as elsewhere in the Markley Formation, kaolinite and overlying organic beds appear to have formed as a single genetic unit, with the kaolinite forming an impermeable aquiclude upon which a poorly drained wetland subsequently formed. Within a single inferred glacial/interglacial cycle, lithological data indicate significant fluctuations in water availability tracked by changes in palynofloral and megafloral taxa. Palynology reveals that elements of the dryland floras appear at low abundance even within wetland deposits. The combined data indicate a complex pattern of succession and suggest a mosaic of dryland and wetland plant communities in the Late Pennsylvanian. Our data alone cannot show whether dryland and wetland assemblages succeed one another temporally, or coexisted on the landscape. However, the combined evidence suggests relatively close spatial proximity within a fragmenting and increasingly arid environment.

Archaeorthoptera is a high rank insect taxon comprising Orthoptera as well as the extinct orders Titanoptera and Caloneurodea, and several other late Paleozoic groups formerly assigned to polyphyletic Protorthoptera. Synapomorphies defining Archaeorthoptera and some fossil subordinate taxa are exclusively based on wing venation. This study presents a detailed description of two new archaeorthopteran genera and three new species from the Pennsylvanian of the Upper Silesian Coal Basin in Poland. These new taxa provide new insights into the wing venation disparity of this remarkable and insufficiently studied insect group. Omaliella polonica sp. nov. is based on a well preserved forewing, including the wing base, which allows a thorough discussion and comparison with other archaeorthopterans. Surprisingly, it is the first complete wing for this group of related genera (Omaliella, Omalia, Coselia and Paleomastax). Owadpteron dareki gen. et sp. nov. has an unusual arrangement of cubital veins. The marked resemblance of the venation of Owadpteron to that of some members of the gerarid line, such as Nacekomia, supports its placement within the family Geraridae (stemgroup Orthoptera). Finally, the venation of Parapalaeomastax dariuszi gen. et sp. nov. strikingly resembles that of the genus Palaeomastax, differing only in the distally branched media. Discovery of these three new archaeorthopterans from the Upper Silesian Coal Basin fits well with that of closely related taxa known from other deposits in Euramerica, such as Mazon Creek Lagerstätte, Avion in Pas-de-Calais Basin and others. Furthermore, a new re-examination of the earliest archaeorthopteran from the Upper Silesian Coal Basin confirms doubtful assignment of this fragmentary fossil to Archaeorthoptera or even to Pterygota.

Colonies of the rugose corals Nemistium liardense sp. nov. and Heritschioides simplex sp. nov. were collected from limestone in the upper member of the Mattson Formation in the Liard Range in the Northwest Territories and are the only known identifiable coral species from the Mattson Fm. The Mattson Fm., deposited in the Liard Basin west of the syndepositional Bovie reverse fault, comprises sandstone with subordinate shale and carbonates deposited during several delta cycles. The close morphological similarity and identical mode of offsetting in N. liardense colonies from the Mattson Fm. and the allochthonous Stikine Terrane of British Columbia indicate they belong in the same species. This and the morphological similarity between H. simplex and the late Serpukhovian to early Bashkirian H. columbicum allow assignment of the coral-bearing part of the upper Mattson Fm. to Bashkirian Foraminiferal Biozone 20. Widespread occurrence of the genus Nemistium confirms open communication between the Liard Basin region and the western European and northern African seas.

The taphonomic and ecological features of the predominantly non-marine fauna and terrestrial flora from two deltaic sandstones in the middle part of the Mospinka Formation (Upper Bashkirian, Lower Pennsylvanian) were studied. The non-marine fauna of the Carboniferous of the Donets Basin is extremely poorly studied. Currently, many groups of animals living beyond the marine environment are known from here (non-marine bivalves, horseshoe crabs, eurypterids, arachnids, insects, ostracods, сirripeds, conchostracs, cycloids and fishes). They have great stratigraphic and paleogeographic significance. Fossil soils from the Bashkirian Stage of the Donets Basin were first studied. In the studied sandstones, the presence of the most ancient red-bedded sediments in the Carboniferous of the Donets Basin was noted. This circumstance, together with the specifics of the composition of communities of peat-forming plants, indicates that during the accumulation of deposits of the Mospinka Formation, against the background of a predominantly humid climate, episodes of temporary increase in climate dryness arose. Microbially induced sedimentary textures in the Carboniferous deposits of the Donets Basin were studied for the first time. For many taxa of fossil plants, the vertical distribution in the section of the Carboniferous of the Donets Basin is specified. The oldest community of non-marine bivalves in the Carboniferous of the so-called Open Donets Basin was studied. In both sandstone beds, the presence of remains and traces of locomotion of giant arthropods of the genus Arthropleura was recorded. Together with them, fossils of large horseshoe crabs and insects are observed. The composition of the richest ichnocenosis in the Carboniferous sediments of the Donets Basin was studied. Among ichnofossils, a trace of a tetrapoda locomotion, as well as traces of arthropods activity on plant organs should be especially noted. Deltaic deposits are rich in orictocenoses, which is associated with a variety of living conditions of organisms and the burial of their remains. The new data obtained are of great importance for reconstructing the living conditions of organisms at the sea-land boundary. The performed studies showed great prospects for studying the non-marine fauna of the Carboniferous of the Donets Basin in order to corellate marine and continental sediments of the Carboniferous of Laurasia.