Description: Arborescent and sub-arborescent lycopsids are important floristic elements of the Brazilian early Permian post-glacial environments. However, the taxonomy and systematic position as well as the biology and ecology of these plants are poorly understood. The present study describes a remarkable assemblage of Brasilodendron cf. pedroanum axes preserved in the plant bearing sub-level N8b of the Morro do Papaléo outcrop, Rio Bonito Formation, early Permian of the Paraná Basin, Rio Grande do Sul state, Brazil. These axes are massively concentrated, without any preferential depositional orientation, forming a monotypical assemblage. They are unbranched and preserved as impressions. Three morphological patterns, occurring on distinct axes, were described for leaf cushions. This mass-assemblage is probably a result of allochthonous deposition and hydraulic size-sorting. The massive concentration of B . cf. pedroanum suggests that this fossil taxon was an important floristic element somewhere in the upstream area of the braided river system studied here.

Description: Flood basalt volcanism has been implicated in several episodes of mass extinctions and environmental degradation in the geological past, including at the Triassic–Jurassic (Tr–J) transition, through global warming caused by massive outgassing of carbon dioxide. However, the patterns of biodiversity loss observed are complicated and sometimes difficult to reconcile with the effects of global warming alone. Recently, attention has turned to additional volcanic products as potential aggravating factors, in particular sulphur dioxide (SO 2 ). SO 2 acts both directly as a noxious environmental pollutant and indirectly through forming aerosols in the atmosphere, which may cause transient global dimming and cooling. Here, we present a range of morphological changes to fossil plant leaf cuticle surfaces of hundreds of Ginkgoales and Bennettitales specimens across the Tr–J boundary of East Greenland. Our results indicate that morphological structures of distorted cuticles near the Tr–J boundary are consistent with modern cuticle SO 2 -caused damage and supported by recent leaf-shape SO 2 proxy results, thus identifying cuticle surface morphology as a potentially powerful proxy for SO 2 . Recording the timing and duration of SO 2 emissions in the past may help distinguish between the driving agents responsible for mass extinction events and thus improve our understanding of the Earth System.

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

Description: Dinosaur footprints are abundant in the Middle Jurassic Ravenscar Group of North Yorkshire, UK. Footprints are particularly common within the Bathonian Long Nab Member of the Scalby Formation and more so within the so-called ‘Burniston footprint bed’ at Burniston Bay. The Yorkshire Jurassic is also famous for its exceptional plant macrofossil and spore-pollen assemblages. Here we investigate the spore-pollen record from the dinosaur footprint-bearing successions in order to reconstruct the vegetation and assess possible dinosaur-plant interactions. We also compare the spore-pollen assemblages with the macroflora of the Scalby Ness Plant Bed, which occurs within the same geological member as the Burniston succession. The spore-pollen assemblages are dominated by Deltoidospora spp., the majority of which were probably produced by Coniopteris . Lycophyte spores (including megaspores) are common in the Yorkshire Jurassic, but lycophyte parent plants are extremely poorly represented in the macroflora. Seed ferns, represented by Alisporites spp., are moderately abundant. Conifer pollen assemblages are dominated by Araucariacites australis (probably produced by Brachyphyllum mamillare ), Perinopollenites elatoides and Classopollis spp., with additional bisaccate pollen taxa. Abundant Ginkgo huttonii in the macroflora suggests that much of the monosulcate pollen was produced by ginkgoes. The diverse vegetation of the Cleveland Basin presumably represented an attractive food source for herbivorous dinosaurs. The dinosaurs probably gathered at the flood plains for fresh-water and also used the non-vegetated plains and coastline as pathways. Although assigning specific makers to footprints is difficult, it is clear that a range of theropod, ornithopod and sauropod dinosaurs inhabited the area.

Description: A palynological and sedimentological study of an outcrop succession adjacent to the village of Kamyanka within the Kharkiv region of northeast Ukraine was carried out. The successions occur within the Dnieper–Donets Basin, which hosts vast successions (〉 20 km) of post mid-Devonian strata and is one of the main hydrocarbon-producing basins in Europe. Middle Jurassic sandstones, siltstones and claystones represent the sedimentary successions at the Kamyanska locality. Few palynological studies have been performed on the Jurassic of Ukraine and even fewer presented in the international literature. Thirty spore taxa and 21 pollen taxa were identified, together with taxa kept in open nomenclature (e.g. bisaccate pollen). Two palynological assemblages were identified within the Kamyanska succession (assemblages A and B) dated as Bathonian. Assemblage A is dominated by the fern spores ( Cyathidites and Osmundacidites ) and gymnosperm pollen produced by Cupressaceae ( Perinopollenites elatoides ), ginkgophytes/Cycadales/Bennettitales (monosulcates) and Cheirolepidiaceae ( Classopollis ). Assemblage B differs in also comprising high abundances of Gleicheniidites  and higher percentages of Pinuspollenites and Araucariacites  compared to assemblage A. Another difference between the two units is the high relative abundance of seed fern pollen ( Alisporites ) in the upper part of assemblage B. The thermal alteration index (TAI) of the palynomorphs is estimated to range from 3 to 3.5, indicating a burial depth corresponding to the mature main phase of liquid petroleum and, to some extent, gas generation. Comparisons between the miospore and macrofloral assemblages show that the palynoflora and macroflora are strongly similar at broad taxonomic levels. Importantly, the miospore assemblages described here compare well with European Middle Jurassic assemblages indicating limited provincialism, with similar vegetation extending from eastern Ukraine and across most of Western Europe.

Description: The Upper Triassic Xujiahe and Lower Jurassic Zhenzhuchong formations of the Sichuan Basin, China, are important sources of plant fossils and windows into the intervening extinction event. However, there is an on-going debate as to whether the environment represented by the Xujiahe and Zhenzhuchong formations was continental or included an important marine component. We studied the Xujiahe–Zhenzhuchong section near Qili Town of Xuanhan County, in the east of the basin and report hummocky and swaley cross-stratification in the Xujiahe Formation. This, along with minor Skolithos and heterolithic bedding, provides strong evidence for shallow marine conditions and favours an interpretation as the deposits of a wave-dominated coast. It also suggests common and extreme storm activity, possibly hurricanes, at what was a mid-latitude (c. 34–40°N) location in the Late Triassic. Charcoal is found in most samples throughout the section. The predominant fossil wood morphology is consistent with Xenoxylon . Together, the sedimentological evidence of storms and fire suggests a highly disturbed environment.

Description: Structurally preserved fossil ferns are extremely significant for exploring the origin and evolution of this plant clade; however, they are quite scarce and limited in the Mesozoic. Here, we report some well-preserved fern rhizomes and rachides with anatomical details from the Upper Jurassic Manketouebo Formation in Inner Mongolia, NE China. Two taxa, including Ashicaulis liaoningensis (Zhang et Zheng) Tidwell referred to Osmundaceae and Gleicheniorachis sinensis sp. nov. referred to Gleicheniaceae, are recognized. Anatomically, Ashicaulis liaoningensis consists of a heterogeneous pith, an ectophloic dictyoxylic siphonostele, a two-layered cortex, C-shaped leaf traces, and a mantle of petiole bases. The petiole base is characterized by a heterogeneous sclerotic ring with an abaxial thick-walled fiber arc. Gleicheniorachis sinensis sp. nov. consists of a C-shaped vascular bundle with two incurved adaxial hooks, a distinct sclerenchyma sheath, an endodermis, and a heterogeneous cortex. In particular, the finding of Gleicheniorachis sinensis sp. nov. represents the first report of unequivocal Jurassic record of Gleicheniaceae in northern China, as well as the first record of a Jurassic permineralized gleicheniaceous fern in the Northern Hemisphere. This study provides new data and evidence for exploring the anatomical diversity and evolution of Mesozoic ferns, and contributes to further understanding the floral composition of Late Jurassic flora in Northeast China.

Description: Several dispersed reproductive organs of bennettitopsid gymnosperms are described and illustrated from Triassic to Cretaceous strata of Australia: Williamsonia eskensis sp. nov. (Middle Triassic), Williamsonia ipsvicensis sp. nov. (Upper Triassic), Williamsonia durikaiensis sp. nov. (Lower Jurassic), Williamsonia sp. (Lower Jurassic), Williamsonia rugosa sp. nov. (Middle Jurassic), Williamsonia gracilis sp. nov. (Lower Cretaceous), Cycadolepis ferrugineus sp. nov. (Lower Jurassic), Cycadolepis sp. (Lower Cretaceous), and Fredlindia moretonensis Shirley 1898 comb. nov. (Upper Triassic). Among these, W. eskensis appears to represent the oldest bennettitalean reproductive structure yet identified. Although global floras expressed less provincialism during the Mesozoic and many genera are cosmopolitan, Australian bennettopsid species appear to have been endemic based on the morphological characters of the reproductive structures. Bennettopsids have a stratigraphic range of around 210 million years in Australia and are widely and abundantly represented by leaf fossils, but only around 20 specimens of reproductive structures, of which half are attributed to Fredlindia , have been recovered from that continent’s geological archive. The extremely low representation of reproductive organs vis-à-vis foliage is interpreted to reflect a combination of physical disintegration of the seed-bearing units while attached to the host axis and, potentially, extensive vegetative reproduction in bennettopsids growing at high southern latitudes during the Mesozoic.

Description: During the Jurassic, Sardinia was close to continental Europe. Emerged lands started from a single island forming in time a progressively sinking archipelago. This complex palaeogeographic situation gave origin to a diverse landscape with a variety of habitats. Collection- and literature-based palaeobotanical, palynological and lithofacies studies were carried out on the Genna Selole Formation for palaeoenvironmental interpretations. They evidence a generally warm and humid climate, affected occasionally by drier periods. Several distinct ecosystems can be discerned in this climate, including alluvial fans with braided streams (Laconi-Gadoni lithofacies), paralic swamps and coasts (Nurri-Escalaplano lithofacies), and lagoons and shallow marine environments (Ussassai-Perdasdefogu lithofacies). The non-marine environments were covered by extensive lowland and a reduced coastal and tidally influenced environment. Both the river and the upland/hinterland environments are of limited impact for the reconstruction. The difference between the composition of the palynological and palaeobotanical associations evidence the discrepancies obtained using only one of those proxies. The macroremains reflect the local palaeoenvironments better, although subjected to a transport bias (e.g. missing upland elements and delicate organs), whereas the palynomorphs permit to reconstruct the regional palaeoclimate. Considering that the flora of Sardinia is the southernmost of all Middle Jurassic European floras, this multidisciplinary study increases our understanding of the terrestrial environments during that period of time.