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The Boguchan floristic assemblage from the Middle Tsagayan subformation of the Zeya–Bureya Basin (Russian Far East) is Paleocene in age according to both palaeobotanical (palynological and plant megafossil) studies and isotope dating of the plant-bearing deposits. It comes from two localities situated in the vicinity of Arkhara Village. The Boguchan assemblage includes 48 fossil plant species belonging to horsetails, ferns, gymnosperms and angiosperms, with angiosperms and taxodiaceous conifers being the most diverse and numerous. For the first time all plant fossils of the Boguchan assemblage are illustrated, the plant-bearing deposits and their correlation between the localities are discussed and two new angiosperm species, Craspedodromophyllum boguchanicum and Archeampelos betulifolia, are described. Variables of palaeoclimate experienced by the Boguchan plants are estimated using CLAMP technique. The Boguchan flora grew in humid temperate conditions with hot summers, mild winters and without dry period during the year (climate Cfa according to the Köppen's classification of global climates). [ABSTRACT FROM AUTHOR]

Premise of research. Four small pollen cones bearing pollen have been found attached to a leafy twig in a calcareous concretion from the Valanginian Apple Bay locality, northern Vancouver Island, British Columbia, increasing the known morphological diversity of Early Cretaceous cupressaceous pollen cones.Methodology. Specimens were prepared using the cellulose acetate peel technique, pollen was examined using SEM, and three-dimensional reconstructions were rendered with Avizo.Pivotal results. The small, subglobose cones bear helically arranged microsporophylls with a central resin canal. Each sporophyll bears three abaxial pollen sacs. Walls of pollen sacs are comprised of radially elongated rectangular cells with prominent wall thickenings. Most pollen sacs are intact and contain numerous, nonsaccate pollen grains. Pollen is 16-24 μm in diameter with one exit papilla that forms a low protuberance on the grain. External surfaces of grains are scabrate with numerous orbicules and macrogranules, and the nexine is laminated. Cone and pollen morphology most closely resemble taxa of the taxodioid Cupressaceae. The number of pollen sacs per microsporophyll is similar to Athrotaxis, Metasequoia, Sequoia, Sequoiadendron, and the Paleogene fossil conifer Homalcoia. Arrangement of cones on branches differs from those of Athrotaxis, Metasequoia, and Homalcoia; pollen lacks the long distal papilla of Sequoia and Sequoiadendron and is most similar in size to that in some cupressoid Cupressaceae in Chamaecyparis, Thuja, and Juniperus but with a smaller aperture.Conclusions. This combination of features is unlike that found in any living or extinct species of Cupressaceae. The fossil species is described as Morinostrobus holbergensis gen. et sp. nov., furthering our understanding of character evolution within Cupressaceae s.l. and adding to the evidence that the Lower Cretaceous was a time of increasing cupressaceous diversity. [ABSTRACT FROM AUTHOR]

Premise of research. Cenozoic macrofloras from South America are fundamental for understanding extant Southern Hemisphere biotas. The Paleogene Ligorio Márquez Formation (LMF) straddles the Chile-Argentina border; leaf fossils from its Chilean outcrops were previously assigned to 150 morphotypes and interpreted as primarily representative of tropical-subtropical lineages, with dominance by diverse Lauraceae of extant Neotropical affinities. Here, we present new collections of Argentine LMF mudstones that are thus far unique in the Patagonian region in containing organically preserved plant fossils, including leaves with cuticular preservation. Methodology. Leaf fossils were exposed by splitting blocks of mudstone or collected by flotation from disaggregated samples. Smaller fossils, including reproductive parts, conifer needles, and isolated cuticles, were recovered from sieved slurry. Fossils were examined under light microscopy, epifluorescence, and SEM. Pivotal results. Twenty taxa were recognized from cuticle-bearing leaf fossils or dispersed cuticles. The most abundant leaf species is a morphologically variable form that is like Lauraceae in architecture but with clearly nonlauraceous cuticular details. Four-parted flower fossils are attributable to the same species, and its eudicot affinities are indicated by adherent triaperturate pollen. Lauraceae were present but much less diverse than reported from the LMF in Chile and arguably with Gondwanan (not Neotropical) affinities. Other taxa include the conifers Dacrycarpus chilensis and Coronelia molinae and possibly Cunoniaceae and a new Ginkgoites. A wet mesotherm paleoclimate is inferred. Conclusions. The new fossils complement and improve our understanding of the LMF and contribute to a greater understanding of high southern latitudes at a time when overland dispersal was possible between South America andAustralasia. The fossils provide further evidence forwarmand humid climates in Patagonia during the early Paleogene and for a stronglyGondwanic flora, with little conclusive evidence of taxa belonging toNeotropical and megatherm lineages. [ABSTRACT FROM AUTHOR]

Hünicken's paleobotanical collection is one of the most important in South America because it was the first one to be related to a documented stratigraphic profile. This floristic assemblage (Oligocene) recovered from Río Guillermo Formation, at Estancia Tres Marías, Río Guillermo Valley, Santa Cruz, Argentina, is described by the first time in this paper. Five species of genusNothofagus(N. subferruginea, N. serrulata,N. crenulata, N. elongataandN. variabilis) together withMyrcia bagualenseare components of the assemblage. The presence ofAcaena brandmayriis confirmed for the first time for the area. Paleoenviromental and paleoclimate implications are also discussed. Characteristic species from a temperate-cold climate such as the genusNothofagusare present in the material studied. A phylogenetic study of the fossil species herein described and the extant South American species ofNothofagusis presented. The preliminary results support the hypothesis that fossil species ofNothogafus are closely related to the modern species. [ABSTRACT FROM AUTHOR]

In order to improve the reliability and accuracy of source rock evaluation, a total of 102 shale samples of Çamalan Formation were collected, analyzed and re-characterized with taking matrix retention effect into account. Results from Rock-Eval and visual kerogen analyses indicate: 1. an excellent source rock with an average TOC of 6.39 wt.%. 2. An assemblage of amorphous (i.e., alginite, type I) organic matter as a major organic constituent with an excellent potential for generating oil. 3. Shale samples from Çamalan Formation are in immature/early–intermediate stage of maturity based on T max (Avg. ∼440 °C) and spore color index (SCI ∼2.5–4). Also no amount of Çamalan generated oils are migrated out of shale based on S 1 vs. TOC plot. (i.e., Transformation ratio (TR ∼0)). Samples of this study show a significant mineral matrix effect. After correction of mineral matrix effect the average hydrogen index (HI) of the Çamalan Formation increased by more than 60 mg HC/g TOC and reached to an average of 811 mg HC/g TOC. Gas oil ratio potential (GORP) factor were used in order to split up the TOC and S 2 into oil-prone and gas-prone and also to investigate the level of consistency between the results of GORP factor and those of visual kerogen studies. Based on obtained GORP factor more than 90% of TOC (live) is composed from oil-prone materials which is in acceptable agreement with petrographic assessments. [ABSTRACT FROM AUTHOR]

* Premise of the study: The Icacinaceae are a pantropical family of trees, shrubs, and climbers with an extensive Paleogene fossil record. Our improved understanding of phylogenetic relationships within the family provides an excellent context for investigating new fossil fruit and leaf material from the Eocene of western North America. * Methods: We examined fossils from early and middle Eocene sediments of western Wyoming, northeastern Utah, northwestern Colorado, and Oregon and compared them with extant species of Iodes and other icacinaceous genera as well as previously described fossils of the family. * Key results: Three new fossil species are described, including two based on endocarps (Iodes occidentalis sp. nov. and Icacinicaryites lottii sp. nov.) and one based on leaves (Goweria bluerimensis sp. nov.). The co-occurrence of I. occidentalis and G. bluerimensis suggests these might represent detached organs of a single species. A new genus, Biceratocarpum, is also established for morphologically distinct fossil fruits of Icacinaceae previously placed in Carpolithus. Biceratocarpum brownii gen. et comb. nov. resembles the London Clay species "Iodes" corniculata in possessing a pair of subapical protrusions. * Conclusions: These fossils increase our knowledge of Icacinaceae in the Paleogene of North America and highlight the importance of the Northern Hemisphere in the early diversification of the family. They also document interchange with the Eocene flora of Europe and biogeographic connections with modern floras of Africa and Asia, where Icacinaceae are diverse today. The present-day restriction of this family to tropical regions offers ecological implications for the Eocene floras in which they occur. [ABSTRACT FROM AUTHOR]