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Abstract: Small spherical structures commonly termed sporocarps are widespread elements in Carboniferous permineralized peat. While sporocarps today are generally interpreted as fungal, their precise systematic affinities largely remain unknown. A specimen of the sporocarp-type Traquairia from the Lower Coal Measures (Lower Pennsylvanian) of Great Britain demonstrates a heretofore unknown feature in the form of a preformed aperture from which emerges a fascicle of radially oriented structures that are constricted sub-distally; transverse septa are present in the constricted areas of some of the structures. The outgrowths are morphologically similar to conidiophores bearing terminal conidia of certain extant fungi in the order Entomophthorales, and thus might suggest affinities of Traquairia with the Zygomycota. Alternatively, the outgrowths might represent sporulating hyphae of a parasitic or saprotrophic blastocladalean fungus or a peronosporomycete that used Traquairia as a nutrient source. [Copyright &y& Elsevier]

Abstract: We examined four dispersed, coalified ovules, Trigonocarpus grandis, of medullosalean seed-fern affinity from the Late Pennsylvanian age Sydney Coalfield, Canada, which represent the larger type of the 7–8cm trigonocarpalean form species. At first glance it appears that the ovules are preserved like the usual Carboniferous foliar compressions, i.e. one coalified layer with one preserved anatomical tissue, the cuticle. However, careful sample preparation uncovered at least three coalified layers, and Schulze’s oxidative maceration process, which dissolves the coalified material, revealed several tissue layers. Altogether, eight sample forms were defined: (i) coalified layer, (ii) cuticle A, (iii) cupric+vitrain, (iv) vitrain, (v) cupric, (vi) cuticle B, (vii) alkaline solution and (viii) added coal seam material. The purpose of the study was twofold: first, to systematically analyze the forms by way of Fourier transform infrared (FTIR) spectrometry to fill a gap in chemical information that exits for coalified trigonocarpalean ovules of Carboniferous seed ferns; second, to use principal component analysis to focus on groupings as a function of chemical structure (functional groups) and to assess the different fossil forms in terms of FTIR chemical parameters, based on a 8×49 data matrix. Results include distinction among the three coaly sample forms, coalified layer (i), cupric+vitrain (iii) and cupric (v), based mainly, but not exclusively, on differences in carbonyl content, as well as length and branching of the polymethylenic chains. Important to note is the high aliphatic content of the cuticles as a signature of the biomacromolecules cutan/cutin. In particular, new insights into the structure of the original ovule are presented, and differences in chemistry are mainly a result of the complex structure of the precursor plant organ. [Copyright &y& Elsevier]

Abstract: The Pennsylvanian and Early Permian were times of extreme sea-level changes of >100 to perhaps up to 200m. For example, glacio-eustatic sea-level changes are well documented from the US Midcontinent, Moscow Basin and Yangtze Platform, where more than 100 stacked subtidal to supratidal sequences have been described. In contrast, carbonates developed in the Ural Mountains and South Guizhou of the Yangtze Platform were deposited in ramp and slope settings. δ13C values of whole rock samples from the US Midcontinent and Moscow Basin were intensively affected by diagenesis. Only well-preserved brachiopod shells maintained their original carbon isotope ratios. In contrast, limestones deposited in the deeper water slope environments were not affected by meteoric diagenesis and are interpreted to have mainly retained their carbon isotope ratios. Mean δ13C values of slope carbonates of the Yangtze Platform increase from about 3‰ during the Viséan and Serpukhovian to 5‰ at the Carboniferous–Permian boundary and decrease to values around 2‰ in the early Kungurian. This positive δ13C excursion coincides with low δ13C values in the Yangtze Platform successions, which were reset by meteoric diagenesis. The highest δ13C values recorded in the slope succession coincide with the inferred maximum glaciation that caused pronounced sea-level lowstands. Short-lived, but significant negative δ13C excursions in the Chinese slope succession are interpreted to reflect changes in ocean circulation due to sea-level rises which caused enhanced production and/or preservation of organic matter which influenced the subsequent early diagenetic cementation. [Copyright &y& Elsevier]

Abstract: A new fossil water mold (Peronosporomycetes), Galtierella biscalithecae nov. gen. et sp., consisting of coenocytic hyphae occurs as an intracellular endophyte in a partially degraded specimen of the reproductive organ Biscalitheca cf. musata (Zygopteridales) from the Upper Pennsylvanian Grand-Croix cherts (Saint-Étienne Basin, France). Some hyphal tips produce small spheres that subsequently develop into ornamented, opaque-walled oogonia; amphigynous antheridia encircle the necks of several immature oogonia. Also present are ovoid structures, which may represent differently shaped oogonia, hyphal swellings, or zoosporangia. Small dome-shaped structures, probably zoospore cysts, are attached to numerous host cell walls. This discovery sheds new light on the morphology and biology of water molds in a Carboniferous ecosystem. [Copyright &y& Elsevier]

Abstract: Conventional (one-dimensional) chemostratigraphy of marine carbonates assesses the chemical archive of individual stratigraphic sections and their correlation in space and time. Whereas this approach has shown to be of value when linking isobathymetric domains, usually characterised by similar facies, more caution is needed when correlations are extended across different physiographic settings and hence different facies belts. Here, the spatial geochemical record of Pennsylvanian platform-margin-to-basin transects across a bathymetric range of about 800 m is documented and discussed in a process-oriented context. Particularly, the presence of layered palaeo-water masses and their potential control on slope facies distribution and geochemical properties requires attention. Whereas Carboniferous thermo- and/or chemo-clines most likely affected depth-related slope facies zonation, it was facies change and hence, variances in porosity–permeability properties, that controlled differential early burial diagenetic alteration. Specifically, the lower-slope related breccia facies is characterised by higher volumes of early burial carbonate cements. This implies that these sediments entered the shallow-burial domain with a considerable open pore space and gave way to an increased rock:fluid ratio. Whereas the δ 13C record is invariant with bathymetry, the more diagenesis-sensitive δ 18O proxy, records pronounced shifts observed across major facies boundaries. From this it is concluded that although the primary controlling factor of slope facies distribution with depth is probably palaeoceanographic in nature, it is differential rock:fluid ratios that control the first-order, spatial shifts in δ 18O composition. These findings show that one-dimensional chemostratigraphy will severely underestimate the complexity of three-dimensional (bathymetric) data sets across platform margins. This is of relevance for the interpretation of the geochemical archive of fossil carbonate platforms in general. [Copyright &y& Elsevier]

Abstract: Late Stephanian and Early Permian floras were collected in eight localities of the Boskovice Basin. More than 2700 specimens were studied. The Carboniferous wet-type flora (Rosice–Oslavany Formation) is relatively hygrophilous with a dominance of ferns (Pecopteris cyathea and P. densifolia) and a smaller representation of sphenopsids (Annularia sphenophylloides). Pteridosperms and cordaitaleans are rare. Conifers (Ernestiodendron filiciforme), as drier-type elements, occur locally above the 1st (uppermost) coal seam of the Rosice–Oslavany coals together with many representatives of pteridosperms (medullosans, Odontopteris schlotheimii). This indicates the beginning of seasonality and aridisation of the climate. The Permian flora is dominated by conifers and is of an arid character. Some horizons contain a relatively high proportion of pteridosperms (Zbýšov, Říčany and Zboněk–Svitávka horizons), however, the species spectrum differs and the Permian pteridosperms are mainly represented by peltasperms (Autunia conferta). Ferns and sphenopsids are extremely rare in the Permian horizons. The flora reflects changes in the basin from relatively wet climate in the Rosice–Oslavany Formation to the seasonal and “dry” climate during the Permian. The Permian extrabasinal floral elements preserved in fossiliferous horizons grew in the basin during the seasonal climate. The red sediments outside the fossiliferous horizons are barren, presumably reflecting a semi-arid climate. The seasonality and “less” or “more” dry periods during the Permian are documented changes in diversity and dominance of the flora, and by cluster analysis. Using unconstrained Jaccard''s analysis, the Carboniferous “wet-type” flora is clearly separated from the “dry-type” Permian flora. Even though the Chudčice Horizon is approximately in the middle of the section, it is placed in this analysis at the top of the dendrogram together with the “dry-type” floral clusters. This analysis reflects an aridisation trend rather than biostratigraphically determined changes. As a result of our excavations, 15 species are here for the first time reported from the Boskovice Basin: Pecopteris cf. bredovii, Remia pinnatifida, Odontopteris lingulata, Neurocallipteris gallica, N. planchardii, Rhachiphyllum aff. curretiensis, ?R. subauriculata, Dicranophyllum longifolium, Culmitzschia angustifolia, Hermitia arnhardtii, H. germanica, H. rigidula, H. schlotheimii, and bifurcated leaves of uncertain affinity. [Copyright &y& Elsevier]

Abstract: About fifty compression specimens belonging to four species of Polysporia from the Kladno–Rakovník Basin of the central and western Bohemian Carboniferous continental basins and Intra-Sudetic Basin of the Czech Republic were studied macromorphologically and for in situ spores. Their stratigraphic range is from the Bolsovian to the Stephanian B. Polysporia rothwellii sp. nov., P. drabekii sp. nov. and P. radvanicensis sp. nov. are proposed as new species. Polysporia is reconstructed as a sub-arborescent plant with a principal axis with sterile and fertile apical portions. P. rothwellii and P. drabekii are preserved only as clusters of micro- and megasporophylls on specimens not in connection to an axis, and their identification and classification is based mainly on in situ spores. Micro- and megasporangia of some specimens of Polysporia occur together on axes, however, usually they are not arranged in a distinct pattern and only occasionally the distinct transition among micro- and megasporangia is to be seen. In situ megaspores are correlated with the dispersed species Valvisisporites auritus (Polysporia radvanicensis and P. drabekii), Expansisporites westphalensis (Polysporia rothwellii) and Triletisporites bohemicus (Polysporia robusta). In situ microspores are correlated with the dispersed species Endosporites zonalis (Polysporia robusta), E. globiformis (Polysporia rothwellii) and E. cf. formosus (Polysporia drabekii). Some of Kidston''s type material of Polysporia from UK was re-examined and yields megaspores of the Expansisporites valvatus-type and microspores of the Endosporites globiformis-type. A review of in situ and dispersed occurrences Valvisisporites, Pseudovalvisisporites, Triletisporites, Expansisporites megaspores and Endosporites miospores is given. [Copyright &y& Elsevier]

Interpretation of continental to shallowmarine sedimentary sequences is commonly based on a perception of the presence of order in the upsection recurrence and/or arrangement of one or more rock types. These patterns of stratal organization span a spectrum of scales, ranging from thick transgressive-to-regressive "sequences" within passive continental margins, to thin upward-shallowing "parasequences" reported from many peritidal carbonate successions. However, in spite of the widespread acceptance of this idea, little quantitative assessment has been conducted to ascertain the relative dominance of stratal order and disorder in sedimentary sections. Because perception of high-frequency stratigraphic repetition is especially prevalent in Pennsylvanian "cyclothemic" terrestrial to marine successions generally coeval with Gondwanan glaciation, hypotheses of stratal order have also been widely linked to possible periodic changes in global sea level. Because of the general importance of implied relations between stratal order and glacioeustasy, lithofacies thicknesses, recurrences, and transition frequencies were examined in outcrops of west-central Illinois which comprise the type region of "cyclothem" deposition in order to evaluate the incidence of depositional cyclicity at this rather intermediate scale of consideration. Data on compositions, thicknesses, and vertical stratigraphic arrangement of 1031 units were derived from measured sections of Wanless, these comprise 11 distinct lithofacies types that span 868 m of section exposed at 44 localities. Philosophically, stratigraphic cyclicity could be represented as expectation in lithofacies thickness, lithofacies recurrence, or as some regular pattern in lithofacies ordering. Frequency distributions of lithofacies thicknesses and stratigraphic separations between recurrent lithofacies are exponential in form; these distributions of stratigraphic intervals would result if horizons of lithologic change or recurrence occurred independently (randomly) in sedimentary successions. Stratigraphic cyclicity manifested as lithofacies ordering is evaluated by considering frequencies with different rock types succeed each other in stratigraphic sections; presumption of cyclothemic order requires that lithofacies' transitions exhibit some manifestation of statistical predictability. Markov chain analyses indicate that most high-frequency transitional order exists at underclay-to-coal horizons. Because underclay development may, in part, reflect a post-depositional (diagenetic) process that was associated with plant growth and coal formation, underclay-to-coal couplets may exist as one lithofacies association (as opposed to two genetically unrelated superjacent units). Few other transitions exhibit statistically significant predictability that cannot be ascribed to linkages between gradational rock types or to low-frequency (formation scale) variation in the bulk rock composition of the aggregate Illinois succession. In addition to these statistical attributes, cyclothemic associations designated in numerically generated random sequences that have the same lithofacies attributes as do the Illinois sections exhibit virtually identical thicknesses and abundances of lithofacies elements as those recognized by Wanless. Thus, we conclude that the classic Pennsylvanian successions in west-central Illinois exhibit no compelling evidence of high- frequency cyclic order, either as regularity in the recurrence or in the compositional ordering of lithofacies elements. On the basis of these considerations, we suggest that thicknesses, recurrences, and degrees of stratal order among Pennsylvanian lithofacies reflect largely uncorrelated durations, intensities, and styles of sediment deposition along the western margin of the Illinois Basin. Moreover, portrayal of cyclothemic order in the Illinois sections was found to be distinct from the rather obvious alternation of marine and terrestrial units that characterize these and many other Carboniferous successions. Presumption of recurrent change in sea level is an assumption that is largely unrelated to the presence or absence of cyclothemic scales of stratal ordering. If these Illinois sections are at all typical of other Carboniferous successions, then "cyclothemic" order, manifested as recurrent and potentially periodic accumulation, may be much less evident than is generally perceived to be the case during this important interval of Earth history. [ABSTRACT FROM AUTHOR]