Organic-walled resting cysts of Protoperidinium parthenopes Zingone & Montresor 1988 were collected from a sediment trap in Omura Bay, western Japan. The cysts are spherical and pale brown in color. The cyst wall has two layers: a thick endophragm with granulate surface, and a thin periphragm. Three complete and incomplete parasutures appear on the surface of the endocyst. The archeopyle formed on the endocyst is basically saphopylic and compound with some combination of complete and incomplete parasutures. The cyst of Protoperidinium parthenopes closely resembles the cyst of Protoperidinium americanum (Gran & Braarud 1935) Balech 1974, but differs in the shape of the periphragm, the cyst diameter, and in the archeopyle.

The Mahakam Delta is a tropical, fluvio—tidally dominated delta prograding onto a mixed siliciclastic—carbonate shelf. Surface sediments were collected from 12 distinctive depositional environments extending from the head of the Mahakam Delta to the shelf edge. Organic matter was extracted from 200 samples by acid digestion, and seven palynomorph types (pollen, embryophyte spores, fungal spores, foraminiferal linings, copepod eggs, tintinnomorphs, and dinocysts) were identified and counted, and their percentages and concentrations calculated. Total organic carbon (TOC), lithology, and depositional environments were recorded for each sediment sample.

The amounts of terrestrial palynomorphs in sediments can be explained by transport and depositional processes, and four groups of environments are identified (tidally influenced, detrital peat beach, lowland rain forest, and marine shelf). Because of tidal flushing of the delta plain, pollen, embryophyte spores, fungal spores and soft plant debris from the soil litter are deposited together with clastic mud at slack-water periods. As a result, all tidally-influenced environments exhibit constant numbers of pollen, embryophyte spores, and fungal spores per unit of TOC. In lowland rain forest sediments, there is minor clastic dilution and the numbers of pollen and spores are three to 10 times higher per unit TOC than in tidally-influenced sediments. In detrital peat beach and marine shelf sediments, the number of sporomorphs per unit TOC is lower than expected because of the selective removal of sporomorph-sized particles by wave action and of dilution with autochthonous marine organic matter respectively.

In contrast, the amounts of marine palynomorphs in sediments are related to the depositional environments. Relative amounts of marine palynomorphs increase gradually offshore, as both the sporomorph percentages and concentrations decrease simultaneously. Once in fully marine conditions, concentrations of marine palynomorphs are comparable in all shelf environments. The marine assemblages are mainly represented by Zooplankton (copepod eggs) and benthic protists (foraminiferal linings), the phytoplanktonic constituent (dinocyst) playing a subordinate role.

A palynological analysis was undertaken on 16 samples from seven piston cores collected along two offshore transects near Seymour and James Ross Islands. Diverse assemblages of reworked marine microplankton (including organic-walled dinoflagellate cysts, cymatiosphaerids, leiospheres, and other acritarchs) and terrestrial palynomorphs (including pollen and spores) were recovered from glacio-marine sediments of late Pleistocene age. Among the reworked taxa, four species belonging to the acritarch genus Palaeostomocystis Deflandre 1937 comprise up to 17% of all palynomorphs. Highest abundances were recorded from sites close to the coast. The potential use of Palaeostomocystis as a proxy for early ice-sheet development on the Antarctic margins is evaluated in light of earlier studies. This evaluation suggests that the high abundances of Palaeostomocystis on the Antarctic Peninsula reflect neritic-type environments (shallow waters, bay-like areas, or marginal seas) and sub-polar to polar conditions as exist in the Bering Sea, Greenland margins, and other subarctic to arctic areas today.

Fossil pollen exhibiting viscin threads are reported from Upper Cretaceous and Paleocene deposits in western Venezuela. The sediments were deposited in a marginal marine environment in an area presently occupied by the northern flank of the Venezuelan Andes. The palynofloras are well preserved and diverse and provide insight into the ancient vegetation of Venezuela.

Pollen-bearing viscin threads from the Upper Cretaceous Mito Juan Formation are assigned to the genus Colombipollis Sarmiento Pérez 1994. The pollen grains are tri(col)porate, normally quite smooth, and most often viewed in an oblate (flattened) state. The viscin threads are on the proximal and distal sides of the pollen and vary in length; they appear to have a simple morphology unlike the complex, ropelike threads seen on pollen of the Onagraceae and some other angiosperm families. All observations to date are made using a standard light microscope but more morphological detail could be revealed using scanning electron microscopy.

The pollen exhibiting viscin threads from the Paleocene Los Cuervos Formation are clearly related to onagraceous types and are assigned to the genus Corsinipollenites Nakomen 1995. The pollen is triporate and the viscin threads originate from the polar regions of the pollen. They resemble pollen reported from Eocene to Miocene deposits in the southern hemisphere (Australia, New Zealand) although are smaller in overall dimensions.

The Venezuelan pollen reported in this paper post date the earliest record of viscin threads in the Turonian of the eastern United States. They represent the first reported forms from the South American region. In modern plants the presence of viscin threads has been related to the development of highly specific plant-pollinator relationships; their presence in the Late Cretaceous and Paleocene in Venezuela may help constrain the timing of the origin of certain insect groups in this area.

In the field of archaeological palynology, charcoal and ash debris in sediments have been among the palynologists' worst enemies. Too often important pollen information is found in the soils of sites near fire hearths where the members of ancient cultures would gather to eat and conduct social activities, and in winter sleep near the fire. For decades archaeological palynologists have searched for ways to remove the thousands of tiny flecks of charcoal and ash in these samples so the fossil pollen can be observed. Until now, no technique has proven adequate for successful charcoal removal without the loss of pollen. We have not completely solved this problem, but we have developed an extraction method that significantly reduces the amount of included charcoal and ash in archaeological sediments. We tested this new extraction procedure on charcoal-laden archaeological sediments from a pueblo site in Arizona. The result demonstrates the advantage of using this new pollen extraction procedure for certain types of archaeological soils.

The extinct, organic-walled, proximochorate dinoflagellate cyst Operculodinium? borgerholtense Louwye 2001 was first described from Miocene shallow-marine deposits of northern Belgium, and has since been documented from the Miocene of the eastern North Atlantic, North Sea, Austria, Hungary, and Egypt. Conventional and confocal light microscopy and scanning electron microscopy are used to reveal new details of the archeopyle, wall structure, and ornament. The archeopyle is shown to have well-defined rather than rounded angles, a distinction we consider significant in assigning this species only provisionally to the genus. Operculodinium? borgerholtense was a euryhaline neritic species highly tolerant of environmental stress, a feature consistent with its morphological variability. Present records indicate a tropical—subtropical to temperate paleoclimatic distribution. It ranges from the upper Lower Miocene to upper Middle Miocene, and promises to be a useful stratigraphic marker particularly in neritic settings where adverse paleoenvironmental factors have excluded other species.

New internal and external structures are described from unusually well-preserved specimens of the acritarch genus Hoegklintia Dorning 1981, recovered from the Lower Silurian Osgood and Estill shales of Kentucky and Estill Shale of Ohio (U.S.A.). The morphological variability of internal features ranges from irregularly dispersed organic remains and clusters of circular bodies within the vesicle, to structures congruent with the contours of the vesicle and processes. External bodies are primarily ovoid, and may have a ‘tube-like’ extension penetrating the vesicle interior. Published studies mention and/or depict Hoegklintia with dispersed internal organic matter, but the specimens illustrated here are the first to exhibit morphologically discernible contents. Evidence suggests that these various entities represent coagulated cell contents, life-cycle stages, or manifestations of parasitism/mutualism.

New species of the fungal form-genus Mediaverrunites Jarzen & Elsik 1986 ex Nandi & Sinha 2007 are described from tropical to warm temperate Neogene strata. Mediaverrunites fournierii sp. nov. and Mediaverrunites magnus sp. nov. occur in the Lower Miocene of Colombia. Mediaverrunites invaginatus sp. nov. is from the Upper Miocene to Lower Pleistocene, offshore Louisiana. The form-genus is also represented by an apparently undescribed extant species occurring in recent sediment.

More than one thousand specimens of a morphological complex including Galeacysta etrusca Corradini & Biffi 1988 from 11 Upper Miocene and Lower Pliocene localities of the Paratethyan and Mediterranean realms have been studied using a biometric approach in part relating to the degree of separation between endocyst and ectocyst. Four stable biometric groups have been distinguished statistically, the occurrence or prevalence of which appears closely linked to environmental conditions irrespective of the realm. Group ‘a’ is related to brackish conditions, group ‘b’ to marine conditions, group ‘c’ to freshwater, and group ‘d’ to high nutrient levels. Based on an accurate chronology provided by calcareous nannoplankton bioevents and recognition of the Messinian Erosional Surface, this study reveals:

Based on field observations and dinoflagellate cyst data, we propose that the reflooding of the Mediterranean Basin by Atlantic waters occurred at ca. 5.46 Ma, about 130 kyr before the Zanclean GSSP (5.332 Ma).

A multidisciplinary project on an archaeological site on the Mitchell River, which feeds into Choctawhatchee Bay on the Florida panhandle, was designed to understand human adaptations to a dynamic hydrological environment during the Middle and Late Archaic period (ca. 8000–3000 B.P.). Now in a freshwater environment, on a sandy terrace above the Mitchell River floodplain, the Mitchell River 1 archaeological site contains an oyster-shell midden and other features indicating human exploitation of an estuarine environment. Estuarine exploitation at the site occurred over a long span of time, from around 7300 to 3400 2cal B.P., although the site was abandoned two or three times over the millennia. The site was more permanently abandoned after 3400 B.P.

Because estuarine shellfish, such as oysters, are low trophic level species, they have been considered marginal resources, and archaeologists modeling collector strategies assume that people will not travel far to obtain them. Under an optimal foraging model, estuarine resources should have been closer to the site than at present. A multidisciplinary team was assembled to address whether a mid-Holocene sea-level highstand had produced estuarine conditions in the Mitchell River floodplain during the Archaic. Using microfossils and stratigraphy from a dated core taken in the floodplain due south of the site, the project members attempted to correlate the changing paleoenvironment with human occupation and abandonment of the area. Results indicate that, at ca. 7300 cal B.P., when the Mitchell River 1 site was first inhabited, the floodplain was a shallow, open, sedge marsh. The site inhabitants must have traveled some distance to gather the oysters and other estuarine species that were discarded on the site. The earliest occupation was brief, but the site was reoccupied between 5900 and 5300 cal B.P., when the floodplain had become a Taxodium/Nyssa swamp. Site deposits indicate intensive exploitation of oyster and to a lesser extent Rangia, which may have been closer to the site than at 7300 B.P. but still would have required some travel. At some point, the mouth of the Mitchell River was forced eastward, and the bayhead delta, recognized as a 2-meter-deep wedge of sand in the core, was located adjacent to the site. By 4700 cal B.P., brackish water conditions prevailed, although direct evidence of oyster beds in the immediate area is lacking. Unfortunately, scouring of the core sediments sometime after 4700 cal B.P. destroyed the paleoenvironmental record for the last part of the Archaic occupation of the site. However, some evidence in Core 1, along with research elsewhere on the Florida panhandle, suggests that catastrophic storms may have played a part in the more permanent abandonment of the site after 3400 B.P.

Experiments are presented here in analysis and depiction of Palynodata records. Palynodata, a database of pre-Quaternary records of fossil palynomorphs compiled from global literature, is now available as Geological Survey of Canada (GSC) Open File 5793. Palynodata is a non-random sample of the distributions of palynomorphs. Hence, for any taxon, occurrence records in Palynodata serve as a proxy for its ‘real’ distribution in geological time and paleogeographical space. These experiments may be useful starting points for students of palynology in their exploration of Palynodata records. Palynoplot software bins and plots Palynodata taxa retrievals by time, and by the modern latitude of the study sites. It uses geographical co-ordinates for the study localities in Palynodata and the geological time scale. Such plots reveal temporal and latitudinal distribution patterns, and potential taxonomic and data problems such as outliers and inconsistent taxonomy. Taxonomic studies can be supported by considering time by latitude distributions, in addition to traditional morphology and priorities. The modern latitude of the sites studied gives increasing distortion with geological age. Palynodata output and the study locality file was input for PaleoGIS software to depict occurrence records on paleogeographical maps. PaleoGIS software showed changing occurrence patterns on rotated plates.

An experimental trend surface model of the Jurassic-Cretaceous transition used binned records of common filicale genera which were evolutionarily sensitive between 180 and 100 Ma. The results demonstrate potential for the technique, and lessons for interpretation and future refinement. Common taxa may become useful for biostratigraphical problems and, by calibration against reference sections, this technique might be refined to provide a useful biostratigraphical standard for geological system boundaries. These manipulations of Palynodata records are a ‘proof-of-concept’ demonstration of techniques that may help to reveal the biostratigraphical, paleoecological, and paleoclimatological significance of fossil palynomorphs. Such work also reveals desirable improvements in Palynodata. The precision of indexing species in Palynodata may limit the potential level of chronostratigraphical resolution.