Two informal sporomorph assemblage zones can be distinguished in the dinosaur-bearing Tendaguru Beds of southeast Tanzanian. The first zone, the Classopollis—Araucariacites—Shanbeipollenites Assemblage Zone, ranges from the Lower to the Upper Saurian Bed, and a mid-Oxfordian to Tithonian age is suggested based on the presence of Shanbeipollenites quadratus. The second zone, the Classopollis—Cicatricosisporites—Ruffordiaspora Assemblage Zone, is restricted in the Trigonia schwarzi Bed, which overlies the Upper Saurian Bed. The combined ranges of Cicatricosisporites hughesii, Ruffordiaspora australiensis and Trilobosporites obsitus would be consistent with a late Berriasian to Hauterivian age of this zone. This is refined further to late Valanginian to Hauterivian on the basis of already existing evidence from fauna and dinoflagellate cysts. From a phytogeographic point of view the Tendaguru locality belongs to the southern Gondwana Trisaccates Province because of the presence of trisaccate podocarpaceous pollen. The quantitative composition of the palynofloras is characterized by the dominance or abundance of pollen produced by the two conifer families Cheirolepidiaceae (Classopollis) and Araucariaceae (mainly Araucariacites). Pollen of Cheirolepidiaceae, typically xerophytic, drought-resistant, thermophilic plants, is dominant throughout the Tendaguru Beds except in parts of the Middle Saurian Bed where pollen of Araucariaceae, a presumably mesic group, becomes most abundant. Classopollis attains the highest degree of dominance in the shallow marine deposits associated with the saurian beds. This may be related to paleoecological and taphonomic factors, namely abundance of Classopollis-producing plants in low-lying coastal environments close to the lagoonlike depositional sites and transportational sorting of sporomorphs leading to a relative enrichment of small and/or anemophilous pollen. The abundance of Araucariacites in the Middle Saurian Bed suggests that araucarians existed in coastal plain environments that were stable enough to allow the growth of large trees. This open araucarian forest, which may have been a source of food for high-browsing dinosaurs, was situated landward of the cheirolepidiacean belt not far from the depositional sites. Pteridophytes and bryophytes were concentrated at moist places and around water bodies. Podocarpaceous conifers producing bisaccate and trisaccate pollen grew in local uplands, while gnetaleans related to Ephedra and Welwitschia may have been present in dry places. The palynological evidence is consistent with a seasonally dry, tropical to sub-tropical paleoclimate. Three new combinations, Equisetosporites certus (Bolkhovitina), Jugella caichigüensis (Volkheimer and Quattrocchio) and Trichotomosulcites microsaccatus (Couper), are proposed, and Jugella semistriata is described as a new species.

Carboniferous rocks in the Joggins area, Nova Scotia, and the Maringouin Peninsula, New Brunswick, are world renowned for their well-preserved macroflora, but this paper is the first detailed study of the palynoflora. The section is comprised of the Mississippian Windsor and Mabou groups overlain disconformably by the Lower Pennsylvanian Cumberland Group. The Windsor Group rocks proved to be barren of palynomorphs but the Mabou Group yielded spores and pollen of Brigantian (late Viséan) to Arnsbergian age (early Namurian = early Serpukhovian). The assemblages are assigned successively to the Schopfipollenites acadiensis—Knoxisporites triradiatus, the Grandispora spinosa—Ibrahimispores magnificus, and the Reticulatisporites carnosus Zones. A major palynofloral change takes place between the Mississippian Mabou and the Pennsylvanian Cumberland assemblages. This is believed to reflect a significant regional hiatus in the Joggins section and elsewhere in eastern Canada. The Cumberland Group is characterized by an abundance of Lycospora spp. and monosaccate gymnosperm species of Yeadonian? (Late Namurian = middle Bashkirian?) to late Duckmantian (late Bashkirian?) age. The palynological succession is divided into the Raistrickia saetosa, the Raistrickia fulva, and the Vestispora magna zones. Age determinations of the zones, based on comparisons with Western Europe and the North Sea, are tentative because the Cumberland assemblages lack diversity and many taxa diagnostic in Western Europe are absent in the assemblages of the Joggins area, possibly due to environmental and climatic differences.

Geological Survey of Canada Contribution Number: 20090031

A palynological investigation of a section dated by foraminifera, at Ouled Haddou, south-eastern Rifian Corridor, northern Morocco, revealed a rich and well-preserved dinoflagellate cyst assemblage that allowed a palynological separation of Maastrichtian from Danian deposits. The gradual change of the dinoflagellate cyst assemblages and the biostratigraphic resolution attained, suggest that the studied Maastrichtian—Danian section is continuous. The recognition of the latest Maastrichtian and earliest Danian is based on global dinoflagellate cyst events, including the first occurrence of the latest Maastrichtian species Disphaerogena carposphaeropsis, Glaphyrocysta perforata, and Manumiella seelandica, the latest Maastrichtian acme of Manumiella seelandica, and the first occurrence of the earliest Danian markers Carpatella cornuta, Damassadinium californicum, Eisenackia circumtabulata, Membrani-larnacia tenella and Senoniasphaera inornata. The Cretaceous—Paleogene boundary is placed above the latest Maastrichtian events, mainly immediately above the acme of M. seelandica and below the earliest Danian events, particularly below the first occurrences of C. cornuta and D. californicum. The biostratigraphic interpretations are based on a comparison with calibrated dinoflagellate cyst ranges from several reference sections, mainly in the Northern Hemisphere middle latitudes. The Cretaceous—Paleogene boundary is not marked by a mass extinction of dinoflagellate cyst species, but shows important changes in the relative abundances of different species or groups of morphologically related species. These changes are paleoenvironmentally controlled. The peridinioid assemblage suggests deposition in a subtropical to warm temperate province. One dinoflagellate cyst species, Phelodinium elongatum, is formally described.

Pollen concentrations containing abundant Zea mays pollen grains are AMS radiocarbon dated 3940 40 to 2450 40 ¹⁴C years BP. The maize pollen is from two prehistoric woodrat (Neotoma) middens that occur in fractures in the south-facing sandstone cliff at Chaco Culture National Historical Park. The diameters of the Archaic-age maize pollen grains are significantly larger than Puebloan and modern maize pollen. The size distributions of the earliest Zea grain populations are not normal, suggesting the possibility that more than one variety of maize is represented by the pollen. The occurrence of large numbers of maize pollen grains as well as pollen from weedy plants indicates the nearby presence of an Archaic cornfield, now buried in alluvial fill adjacent to the cliff. It was also found that the AMS radiocarbon ages of the pollen concentrations differ significantly from the age of twigs from the same woodrat middens. Because of the strong age differences of components of woodrat middens, pollen assemblages should be dated independent of plant macrofossils.

Maranhites isaacsonii sp. nov. was recovered from an outcrop sample of the Upper Devonian Cabanillas Group, Oxapampa Province, Peru. This acritarch displays the discrete equatorial thickenings that characterize the genus, but differs from all described species by having a lobate vesicle margin with processes or process groups. The processes taper distally and terminate in capitate, rounded, or clavate tips. The palynomorph assemblage is dominated by marine elements, including acritarchs, prasinophytes, scolecodonts, and chitinozoans. The occurrence of Retispora lepidophyta indicates a Late Famennian—Early Tournaisian (Fa2c-Tn1a) age for the sample yielding Maranhites isaacsonii sp. nov. Palynomorphs exhibit a thermal alteration index equivalent to gas-window maturation.