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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]

This study documents the terrestrial palynological record at the John's Nose section, a new Cretaceous–Paleogene (K–Pg) boundary site in North Dakota, USA. In addition to Mud Buttes and Pyramid Butte, John's Nose represents the third K–Pg section in southwestern North Dakota that preserves direct evidence of the Chicxulub asteroid impact, allowing for direct comparison over the timing and trends of the palynological record in respect to this event. The palynological analysis of John's Nose section reveals the presence of 68 pollen and spore taxa. Immediately above the boundary clay, a high abundance of fern spores of the genera Cyathidites and Laevigatosporites is recorded (with 59% of the assemblage being represented by Cyathidites). This very distinctive K–Pg ‘fern spike’ event is correlated with the devastation of land plants immediately following the asteroid impact and matches the composition generally reported from other sites in southwestern North Dakota. Palynostratigraphy demonstrates that the placement of the K–Pg boundary based upon the identification of the Last Appearance Datum (LAD) of typical Maastrichtian taxa (K-taxa) may be misleading. The presence of occasional K-taxa up to a few meters above the boundary clay at John's Nose represents an important difference when compared to previous reports. In light of this observation, LADs should be used cautiously as the primary criteria to identify the boundary; some K-taxa may have a short-term presence in the earliest Paleogene, or be reworked. In the John's Nose section, major changes and extinction in the palynological record occur at the geochemical K–Pg boundary, indicating that a catastrophic turnover took place over a short time. [ABSTRACT FROM AUTHOR]

Dinocysts recovered from sediments related to the Chesapeake Bay impact structure in Virginia and the earliest Eocene suboxic environment in Maryland show strange and intriguing details of preservation. Features such as curled processes, opaque debris, breakage, microborings and cyst ghosts, among others, invite speculation about catastrophic depositional processes, rapid burial and biological and chemical decay. Selected specimens from seven cores taken in the coastal plain of Virginia and Maryland show abnormal preservation features in various combinations that merit illustration, description, discussion and further study. Although the depositional environments described are extreme, many of the features discussed are known from, or could be found in, other environments. These environments will show both similarities to and differences from the extreme environments here. [ABSTRACT FROM AUTHOR]

Leaf fossils of Rosa lignitum Heer have often been documented as an accessory element in mixed mesophytic forests from the Oligocene and Miocene of central Europe. Its relationship to extant rose species is not yet firmly understood because leaf morphology contributes only marginally to the current taxonomy of the genus Rosa L. In this study, we investigate which extant rose species have structural leaf characters most similar to those of R. lignitum and whether the distribution and ecology of these extant species fit with the conditions hypothesized for the paleovegetation containing R. lignitum. Therefore, we examined the leaf characters of 32 extant rose species for their diagnostic value in taxonomy and compared these data with characters observed in R. lignitum from five Paleogene floras in central Europe. Most remarkably, we detected semicraspedodromous venation in R. lignitum. This venation pattern was found only in a few species of Rosa distributed in Southeast Asia, whereas the majority of extant rose species developed strictly craspedodromous venation. The distribution of extant species with semicraspedodromous venation in mixed broad-leaved deciduous and evergreen forests in subtropical China clearly corresponds to the hypothesized mixed mesophytic forests in the European paleovegetation. Thus, this study of detailed leaf morphology of Rosa again supports the previous assumption that the zonal vegetation of the central European Oligocene is partly comparable to extant forest types in Southeast Asia. [ABSTRACT FROM AUTHOR]

Normapolles pollen, fern spores, recent fungi and other palynomorphs were traced and identified from a sample of calcareous/ /clayey deposits from the Gombasek Quarry in eastern Slovakia (Rožnava district). Normapolles, pollen of the extinct angiospermous plants, dominated the spectrum, spores of ferns were also frequent. Presence of these types indicate a Mesozoic (Upper Cretaceous) to Early Paleogene age of the source rocks. The assemblage is mixed with specimens of recent fungi spores , remains of algae and rare gymnosperm and angiosperm pollen grains (Pinus, Asteraceae). Significant Tertiary (Paleogene) taxa were not discovered there. The study produced several new records of taxa which had not been found at this locality previously . [ABSTRACT FROM AUTHOR]

Abstract: Investigations of previously undescribed material from the early Maastrichtian (Late Cretaceous) Walbeck flora in Sachsen-Anhalt, Germany provide the first evidence for the occurrence of fossil Metasequoia in continental Europe. The material consists of a few fragmentarily preserved seed cones. This record confirms a long-held assumption that the genus was present in mid-latitude areas in central Europe as was proved before in similar regions in North America and Asia. Its disappearance from central European palaeovegetation during the early Palaeogene might have been caused by palaeoclimatic conditions, while the reasons for the putative absence in the (Atlantic-) Boreal province of Central Europe during the Neogene are still unknown. [Copyright &y& Elsevier]

Abstract: A new formation, the Ketavik Formation, is proposed for Paleogene rocks of Katmai National Park near Brooks Camp. The type section is in an area previously mapped as the Jurassic Talkeetna Formation. The proposed formation was deposited in a fluvial environment. It is distinct from the coeval Copper Lake Formation on the southeast side of the Alaska Peninsula volcanic arc and was deposited in a different river system. The Ketavik Formation may include previously mapped, undifferentiated Tertiary rocks, at least some of which are similar in age, that are scattered along a belt parallel to and northwest of the present magmatic arc. The Ketavik Formation contains dicot and coniferous leaf and wood fossils that indicate a warm temperate climate. [ABSTRACT FROM AUTHOR]

Abstract: The stable carbon isotopic compositions (δ 13C) and chain-length distribution [ACL and n-C31/(n-C29 + n-C31)] of sedimentary leaf wax n-alkanes were investigated across the Cretaceous–Paleogene (K–Pg) boundary at Loma Capiro, Central Cuba, to reconstruct paleoenvironmental changes that are recorded in terrestrial higher plants. The stratigraphic profiles of the n-alkane δ 13C values show a negative excursion in the lowermost Paleocene, although its magnitude is much smaller (∼0.3‰) than the global signals (1.5 to 2.0‰) in the surface ocean-atmospheric carbon reservoir. Relations between the n-alkane δ 13C values and the C31/(C29 +C31) ratios exhibit two different trends, suggesting that our δ 13C records are likely affected by two types of paleoenvironmental factors in addition to the δ 13C variations in the exogenous carbon reservoir. Rare occurrence of terrigenous organic matter that is usually transported by rivers suggests that the n-alkanes at Loma Capiro are likely to have been transported by trade winds, which recorded paleoenvironmental conditions of the northwestern part of the African continent. The n-alkane δ 13C values show a parallel decrease with the ACL and C31/(C29 +C31) values in the first 37,000yr following the K–Pg boundary. Such decreases are consistent with plant physiological responses to reduced net evaporation, suggesting a possible influence of the impact-induced warm-humid condition in the early Paleocene. In contrast, the n-alkane δ 13C values are negatively correlated with the C31/(C29 +C31) ratios from 40,000 to 67,000yr after the K–Pg boundary. This time period matches well with that required for the recovery of terrestrial floras from the K–Pg mass extinction to those with diversity equivalent to the late Cretaceous, suggesting that the n-alkane signals are also likely affected by the plant diversification process after the mass extinction. [Copyright &y& Elsevier]

Abstract  Rockshelter Baaz in the Damascus region of Syria provided a variety of botanical remains from the Late Pleistocene and Early Holocene period. These remains provide new information about the vegetation evolution in this region. The earliest occupational levels correspond with a moisture peak during the Late Pleistocene, between ca. 34–32 kyr b.p., when pine expanded. The next occupations took place during extreme arid conditions, ca. 23–21 kyr b.p., and probably during the Last Glacial Maximum when a steppe vegetation was established. The occupation level of the Younger Dryas, represented by Natufian remains, suggests that the area had been covered by almond-pistachio steppe, similar to later periods of the Early Holocene, and was probably located just outside the range of dense wild cereal stands. There is no drastic impact of the Younger Dryas visible on the vegetation in the botanical remains. The lack of fruits and seeds at Baaz indicates that the site was more likely to have been a temporary hunting post rather than a plant processing site for much of its history. It is ideally suited to this purpose because of its location over the Jaba′deen Pass and the associated springs. However, archaeological remains from the Natufian period, suggest that the site was more permanently occupied during this time. [ABSTRACT FROM AUTHOR]

Presents an abstract of the study `Endocarps of Mastixia and Langtonia (Cornaceae) from the Paleogene of western North America,' by Bruce H. Tiffney and Kristina K. Haggard and presented during the 1995 Annual Meeting of the Botanical Society of America.