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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]

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: 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]