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The mid-Tournaisian black radiolarian cherts of the Lydiennes Formation are exposed in deep-shelf successions of the Puech de la Suque and Col des Tribes sections of the Mont Peyroux Nappe area in the Montagne Noire, southern France. This interval represents the mid-Tournaisian anoxic event that is also termed the Lower Alum Shale Event. This event is associated with a global marine transgression that was characterized by increased productivity and drastic facies changes from pelagic carbonate sedimentation to the widespread deposition of black organic-rich siliceous shales and radiolarites in many parts of the world. In the present study, high-resolution inorganic geochemistry and framboidal pyrite analyses were employed to decipher changes in depositional conditions during the mid-Tournaisian anoxic event in the Montagne Noire. The results show that the total organic carbon contents of sediments associated with the Lower Alum Shale Event vary from 0.09 to 1.9 wt %. These low to moderate total organic carbon contents, high U/Th, low Corg/P and intermediate V/Cr ratios, enrichment in redox-sensitive trace elements, such as U, Mo and V, as well as varying sizes of pyrite framboids, indicate periodic dysoxic to anoxic bottom-water conditions during deposition of the studied sediments. Anomalous Hg spikes (>500 ppb) are also reported in the mid-Tournaisian deep-water marine succession of the Montagne Noire in the present study, which confirm a possible influence of increased regional volcanic activity during this environmental turnover.

The Tournaisian and Visean were formerly considered as series and in Belgium were divided into two (Hastarian and Ivorian) and three stages (Moliniacian, Livian and Warnantian), which are now considered as substages. The Belgian substages are based on conodonts and foraminifers, and incidentally on rugose corals, and are described here. Their boundaries, biostratigraphy and sequence stratigraphy are well detailed and clearly defined. The base of the Hastarian (lower Tournaisian) corresponds to the base of the Tournaisian (base of Carboniferous); the base of the Ivorian (upper Tournaisian) corresponds to the appearance of the conodont Polygnathus communis carina, a little above the last Siphonodella; the base of the Moliniacian (lower Visean) corresponds to the base of the Visean stage defined by the first occurrence of the foraminifer Eoparastaffella simplex; the Livian (middle Visean) corresponds to the foraminiferal MFZ12 Zone and is marked by the appearance of Koskinotextularia and Pojarkovella nibelis; the base of the Warnantian (upper Visean) is marked by the appearance of Neoarchaediscus, Vissariotaxis, Planospirodiscus, and Palaeotextularia with a bilaminar wall, the index taxa of the MFZ13-Neoarchaediscus Zone. The up-to-date chronostratigraphic subdivision of the Tournaisian and Visean is not limited to Belgium and the surrounding areas. It can be applied through Eurasia as far as South China. The Belgian units could therefore be the basis for a future international division of the Tournaisian into two parts (Hastarian and Ivorian) and of the Visean into three parts (Moliniacian, Livian and Warnantian), corresponding to time intervals of c. 5-8 Ma.

Nine crinoids are described from the Wooster Shale Member of the Cuyahoga Formation from Wayne and Ashland counties, Ohio, USA. Identifiable elements of the fauna include five camerate crinoids, one flexible crinoid, and three other eucladid crinoids. Five new species are described, including Cactocrinus woosterensis n. sp., Cusacrinus brushi n. sp., Agaricocrinus murphyi n. sp., Decadocrinus laevis n. sp., and Decadocrinus inordinatus n. sp. Overall, the distribution of crinoid clades in the Wooster Shale is similar to that of the stratigraphically lower Meadville Shale Member of the Cuyahoga Formation, although less diverse and with only one species (Cyathocrinites simplex) in common. Many of the Wooster Shale Member crinoids are completely or partially preserved with siderite either in nodules or within siderite beds. These crinoids are commonly preserved in trauma postures, which is characteristic of burial in episodic high turbulence events. The paleoenvironments and taxa of the two Cuyahoga Formation crinoid faunas more closely resemble Viséan faunas in siliciclastic settings than typical carbonate faunas of the Tournaisian.

The Drewer quarry located in the Rhenish Massif is a well-studied outcrop that comprises Upper Devonian (Famennian) to Lower Carboniferous (Viséan) strata. Within the Drewer deposits two black shale intervals have been described that are linked to two global oceanic anoxic events, the Hangenberg Event and the Lower Alum Shale Event. The black shales associated with the Middle Tournaisian Lower Alum Shale Event contain abundant phosphatic concretions, which were investigated using thin section petrography, powder X-ray diffraction, Fourier-transform infrared spectrometry and scanning electron microscopy. The concretions formed during several growth phases under anoxic and at least episodically sulphidic conditions within the sediment and served as a substrate for subsurface microbial mats that formed phosphatic microstromatolites. The microstromatolites occur either as partially branched columns of up to 600 µm in length attached to the phosphatic concretions or as smaller, bulbous aggregates surrounding the concretions. Element mapping identified the presence of pyrite and other metal sulphides within the phosphatic microstromatolites. The carbon and oxygen stable isotopic composition of phosphate-associated carbonate within the phosphatic microstromatolites suggests that the mat-forming microorganisms were probably anaerobic, chemotrophic microbial communities dwelling in the anoxic environment during the Lower Alum Shale Event. Such interpretation agrees with the deeper-water depositional setting of the Lower Alum Black Shale and its high content of organic matter, suggesting that chemotrophic microbial mats are potent agents of phosphogenesis in general, and of the formation of phosphatic stromatolites in particular.

Among fossiliferous marine facies, deposits rich in stalked echinoderms, particularly encrinites, have long been suspected to be susceptible to taphonomic biases because intact calyxes are under-represented or masked by disarticulated skeletal debris. In the middle Mississippian Fort Payne Formation of south-central Kentucky, penecontemporaneous crinoid-rich facies are exposed in close proximity along the shores of Lake Cumberland. Crinoidal packstone buildups preserve a broad preservational spectrum, with articulated crinoid calyxes with arms and columns attached, intact calyxes, holdfasts, and long articulated columns, in a matrix of entirely disarticulated crinoidal fragments. Along a 250 m transect across the flanks and crest of this buildup, identification of 563 specimens of crinoids and blastoids revealed a symmetrical distribution of taxa in which the crest was dominated by disparid and camerate crinoids and the flanks were dominated by camerates. Taphonomic analysis of the same transect showed that intact crinoid calyxes with or without attached arms and column occurred across the entire buildup, but nearly complete specimens with attached arms and column were most common on the western flank and less common on the crest and eastern flank. Taxonomic and taphonomic distributions demonstrate a primary ecologic zonation across the buildup with only localized post-mortem dispersal of crinoids. This is the first demonstration of primary ecologic zonation of a crinoid community preserved within a single lithofacies. Depending on depositional and taphonomic circumstances, crinoids are preserved intact close to their living site; understanding these physical and biological processes provides a significant feedback in reconstructing these ancient depositional environments.

Terrestrial palynomorphs from the siliciclastic rocks of the Hørbyebreen and Mumien formations in the Birger Johnsonfjellet area, Spitsbergen are documented, providing new knowledge of the stratigraphical ranges of the recorded taxa. Together with a reassessment of previous palynological work in the light of recent advances in palynology, the definitions of three informal palynological assemblages are established. These are correlated to the Carboniferous miospore biozones of Western Europe but differences in the stratigraphical ranges are recorded, as Spitsbergen is located in a different paleofloristic province. Paucity of palynological data from the Arctic areas, as well as lack of independent age control, hampers exact age assignment of the palynological assemblages described. Two age alternatives of the lower part of the Hoelbreen Member are discussed, with the most plausible age for the studied section being mid to late Visean in age. A more consistent and up-to-date correlation of the Mississippian palynofloras in the Arctic region is provided, demonstrating similarities to other Arctic regions. The new age reassessment also improves knowledge of stratigraphical breaks in the succession, providing better understanding of the tectono-stratigraphical history of the region.

The Batocrinidae are characteristic faunal elements in Lower Mississippian shallow-marine settings in North America. Recent delineation of objectively defined genera allows a reexamination of batocrinid species and their distribution in the Fort Payne Formation (early Viséan, late Osagean), a well-studied array of carbonate and siliciclastic facies. The Fort Payne batocrinid fauna has 14 species assigned to six genera, plus hybrid specimens. Magnuscrinus spinosus (Miller and Gurley, 1895a) is reassigned to its original placement in Eretmocrinus. Hybrid specimens (Ausich and Meyer, 1994) are regarded as Eretmocrinus magnificus × Eretmocrinus spinosus. Macrocrinus casualis is the dominant species of Macrocrinus in the Fort Payne, and M. mundulus and M. strotobasilaris are recognized in the Fort Payne Formation for the first time. Magnuscrinus cumberlandensis n. sp. is named, 13 species are designated as junior synonyms, the name for the hybrid specimens is changed to Eretmocrinus magnificus × Eretmocrinus spinosus, and the previous occurrences of two species in the Fort Payne are rejected. The Eastern Interior Seaway was a mixed carbonate-siliciclastic setting with both shallow- and deep-water epicontinental sea facies ranging from relatively shallow autochthonous green shales to deep-water turbidite facies. Dizygocrinus was restricted to shallow-water carbonate and siliciclastic facies, Eutrochocrinus was restricted to shallow-water carbonate facies, and Magnuscrinus was restricted to deep-water facies. Species distributions varied from Abatocrinus steropes, Alloprosallocrinus conicus, Macrocrinus mundulus, and Uperocrinus nashvillae, which occurred throughout the Eastern Interior Seaway, to species that were restricted to a single facies. Eretmocrinus magnificus, Alloprosallocrinus conicus, and Uperocrinus robustus were the dominant batocrinids in the Fort Payne Formation. UUID: http://zoobank.org/703aafd8-4c73-4edc-9870-e2356e2d28b8

The morphology and growth habits of Evactinopora species of the Evactinoporidae (new family) are documented. This distinctive family of free-living bryozoans has a radial colony form at all growth stages. During a brief attachment phase on a hard substrate, the colony morphology grew as an expanding cone with vertical folds. Following detachment of the nascent colony from this hard substrate, it settled on soft sediment and the free-living expanding colony acquired a star-like form by producing slender outrigger rays. Continued growth produced a radial array of vertical vanes containing feeding autozooecia. The colony maintained a vertical orientation on soft sediment by means of outrigger rays and secretion of solid skeleton on the colony base that provided ballast. The radial growth pattern, outrigger rays, and vertical vanes developed as adaptive characters suitable for free-living life on soft sediment. North American species of Evactinopora are redefined and described taxonomically on the basis of zoarial and zooecial characters and a new species, Evactinopora mangeri, erected. The new family Evactinoporidae is established on the basis of the novel characters of early colony detachment from a hard surface, radial growth pattern through life, generation of outrigger rays, and growth of vertical vanes from the top of rays.

Palynological analysis of the Shishtu 2 Member (Shishtu Formation) located in the Howz-e-Dorah area (southeast Tabas, central Iran Basin) suggests a middle Tournaisian—late Viséan age for this rock unit. The Shishtu 2 Member consists of shale, sandstone, dolostone and limestone. Three palynological assemblages are recognised and mainly correlated with the miospore biozones of Northern Gondwana. A microfloristic comparison with other sections in Western Gondwana (South America) is also proposed. We identify a sedimentary hiatus between the Shishtu 1 and Shishtu 2 members. Our findings suggest that the Mush Horizon is the lowermost part of the Shishtu 2 Member, contrary to the Iranian literature where it is considered to be the uppermost part of the Shishtu 1 Member.

This assessment of the article by Aria-Nasab et al. (2016), on the palynostratigraphy of the upper part of the Shishtu Formation (Shishtu 2) in central Iran, reveals many shortcomings. The majority of the defects are judged to reflect unwarranted or erroneous taxonomic identifications of the adversely preserved miospores. This, in turn, casts considerable doubt on the compositional integrity of Aria-Nasab et al.'s three proposed stratigraphically successive miospore assemblages, which they dated as encompassing the mid Tournaisian through late Visean; i.e. within the generalised Mississippian age for Shishtu 2 that had previously been established from marine faunal evidence. We confirm, through examination of their illustrations, the presence of recycled Late Devonian palynomorphs, including Retispora lepidophyta. A late Tournaisian through late Visean or early Serpukhovian age for the sampled Shishtu 2 section is suggested here.