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Palynostratigraphy across the Permian—Triassic of the Salt Range and Surghar Range area remains poorly known because of the predominance of unsuitable facies and preservation (Nammal, Chhidru, Chitta-Landu and Narmia). Dolomite and limestone in the basal Mianwali Formation prevented the establishment of a palynostratigraphic scheme for the basal Early Triassic (Hermann et al. 2012). Based on the study of a new Permian—Triassic section in the Amb valley where siltstone layers are intercalated in the basal Mianwali Formation (Kathwai Member), we describe a new record of palynological assemblages from the uppermost Permian Chhidru Formation and the lowermost part of the Early Triassic Mianwali Formation. The latest Permian Chhidru 2 sporomorph association occurs in the uppermost part of the Chhidru Formation, the so-called ‘white sandstone unit’. It is marked by the dominance of bisaccate pollen grains (mainly Protohaploxypinus spp.) and cavate trilete spores (mainly Kraeuselisporites spp.). Here, the previously described lowermost Triassic palynozone PTr 1 is subdivided into two subzones. PTr 1a assemblages are described from the Griesbachian Kathwai Member. They are characterized by continued high bisaccate pollen grain abundances and the presence of the lycopod genera Lundbladispora spp. and Densoisporites spp. In these assemblages, typical ‘Permian taxa’ and typical ‘Triassic taxa’ are mixed. The composition of the middle Dienerian PTr 1b assemblages corresponds to the previously described PTr 1 assemblage from Nammal and Chitta-Landu. Lundbladispora spp. and Densoisporites spp. account for ca. 80% of the total assemblage in PTr 1b. Although the Griesbachian assemblages record a decrease in diversity, the middle Dienerian assemblages represent the poorest assemblages of the studied Permian—Triassic interval. Reduviasporonites occurs only sporadically throughout the Amb succession.
The palynology of 16 species of Aizoaceae and Molluginaceae distributed in Egypt and Sudan were studied by light microscopes (LM) and scanning electron microscopes (SEM). Pollen is generally 3-zonocolpate, suboblate, oblatespheroidal, prolate-spheroidal, subprolate or prolate. The polar axis ranges from 16.9 to 44.4 µm, while the equatorial diameter ranges from 15.3 to 33.2 µm. Pollen shape is trilobate, triangular or circular in polar outline and elliptic, ovate or apiculate in equatorial outline. Sculpturing is microechinate, punctate-scabrate, scabrate, sparsely punctate; microechinate, reticulate-striate or microechinate, psilate. Six pollen types were recognized, viz. the Limeum pollen type, the Mesembryanthemum nodiflorum pollen type, the Mollugo pollen type, the Mesembryanthemum crystallinum pollen type, the Zaleya pollen type and the Aizoon hispanicum pollen type. Descriptions of each type and a key to investigated taxa, as well SEM micrographs of pollen types, are provided. Moreover, numerical analysis on the basis of Unpaired Group Method of Average (UPGMA) clustering and factor loadings to pollen data led us to recognize six major clades. Four of them have only one species out of the total species number. The fifth major clade includes eight species, while the sixth major clade has four species.
Six new acritarch species were observed during a high-resolution study on the upper Burdigalian to Serravallian (lower and middle Miocene) of the Porcupine Basin (Integrated Ocean Drilling Program Leg 307, off southwestern Ireland). The stratigraphical ranges and palaeoenvironmental preferences of the six new species were assessed. Cometesphaera bullatio gen. et sp. nov. is recorded from the upper Burdigalian to the lower Serravallian, while the range of Cymatiosphaera? deverteuilii sp. nov. is restricted to the upper Serravallian. Platycystidia manumii sp. nov. is recorded from the upper Burdigalian to the upper Langhian. Porcupinea collaris gen. et sp. nov. and Porcupinea indentata gen. et sp. nov. range from the upper Langhian to the lower Serravallian, and from the uppermost Burdigalian to the upper Serravallian, respectively. Pusillisphaera solaris gen. et sp. nov. is recorded from the from the upper Burdigalian to the upper Serravallian.
This study undertook an investigation of an important problem, so far completely overlooked in the palynological literature — to determine the optimal sample size for pollen grain morphological studies. In other words, we investigated the number of pollen grains which should be measured in order to obtain a representative mean value of a given quantitative feature which, in consequence, would make it possible to more accurately describe the pollen of a given taxon. Investigations were conducted on a sample comprising 3850 Rosa canina L. pollen grains on the basis of the length of the polar axis (P), the equatorial diameter (E) and the P/E ratio, at the flower, specimen and population levels. The size of the pollen samples analysed reflected common sample numbers employed in previous pollen morphology studies, namely from five through 10, 20, 30, 50, 100 up to 200 pollen grains. The statistical analyses performed revealed a relatively low variability in pollen grain biometric features at the levels of flower, specimen and population. At the lowest level of variability analysed, it is sufficient to take measurements of several grains to obtain values satisfactorily representing the variability within the flower level. At the level of a specimen or population, the number of grains necessary to secure representative mean values should range from 15 to 20. However, when the research objective is not only information regarding mean values of pollen grain biometric features but also the analysis of their variability (min—max), then the sample size should include approximately 30 grains. The results obtained, apart from their significance in taxonomic studies, also possess important practical significance; measurements of pollen grain biometric features are very labour-intensive and costly and, sometimes, because of difficulties in obtaining satisfactory quantities of plant material (e.g. herbarium specimens, rare species, paleopalynological collections), also very sparse.
Extra-Amazonian Brazil comprises a region with vegetation formations representing the Caatinga (drylands), Cerrado (neotropical savanna), Atlantic Forest, Pantanal (seasonally inundated) and Pampa (grassland) biomes with high species richness. Twenty-five species of Cestrum occur in this region, of which 23 are palynologically examined here with the purpose of contributing to the taxonomy of the genus: C. axillare Vell., C. bracteatum Link & Otto, C. corcovadense Miers, C. corymbosum Schltdl., C. euanthes Schltdl., C. gardneri Sendtn., C. intermedium Sendtn., C. latifolium Lam., C. mariquitense Kunth, C. martii Sendtn., C. montanum Miers, C. obovatum Sendtn., C. parqui L'Hér., C. pedicellatum Sendtn., C. reflexum Sendtn., C. retrofractum Dunal, C. schlechtendalii G. Don, C. strictum Schott ex Sendtn., C. strigilatum Ruiz & Pav., C. subpulverulentum Mart., C. subumbellatum Vignoli-Silva & M. Nee, C. tubulosum Sendtn. and C. velutinum Hiern. The pollen grains were acetolyzed, measured, described and photomicrographed using light microscopy; non-acetolyzed grains were analyzed using scanning electron microscopy. The pollen grains were found to be medium and/or large, isopolar, subprolate, oblate-spheroidal, spheroidal, suboblate or prolate-spheroidal in most species, 3-colporate, endoaperture lalongate, fastigiate, rugulate, rugulate-striated or rugulate-areolated and psilate, or not, in determined regions. The results indicated that the taxa studied demonstrated sufficient pollinic heterogeneity of their shapes, aperture attributes and sexine ornamentation to enable palynological characterization of the species.
The Late Pliocene (3.6–2.6 Ma) was a period of significant global warmth, considered a potential analogue for future anthropogenic climate change. Newly discovered fine-grained sediments from between the gold-bearing lower and upper White Channel Gravels show the presence of a wetland or lake within Bonanza Creek, Dawson Mining District, Yukon. This environment was surrounded by a diverse Pinaceae-dominated boreal forest with significant stands of angiosperms in favourable sites. Quantitative climate reconstructions derived from pollen and spores reveal a mean annual temperature at least 6 °C warmer than today with warm summers and relatively mild winters. Finally, the new pollen assemblage is used to discuss the age of the White Channel Gravels.
An important compendium of fossil fungi is now publicly available through a searchable online database. The original compendium was the work of Kalgutkar and Jansonius, who combed through 238 references and collated and annotated published descriptions for 1783 taxa of fungal fossils. By translating these data to a FileMaker Pro database and to the Web, we increase options for searching, sorting, annotating and updating this information. Database search results provide lists of names, ages and thumbnail images of palynomorphs. An individual record from the results list can be expanded in a new browser window to show a complete description for a taxon. The database is timely because developments in molecular systematics are helping to place spore characters in a phylogenetic framework. Some of the previously ambiguous fossil fungi can now be placed into phylogenetic lineages. We anticipate that the Web version of the data will serve as a convenient entry point into the fungal fossil record, leading to integration of more information from fossils into fungal phylogenies.
Colour is one of the features that differentiate the types of honeys, perhaps the attribute that has the most power of attractiveness to consumers, who tend to value light honeys. Nevertheless, there is no research to date showing the botanical origin of light honeys from Piauí, and neither separating them from the dark ones, using the pollen spectrum. Aiming to characterise botanical origin from pollen grains, samples of light honey produced in the state of Piauí, and also investigating the possibility of differentiation between light and dark honey through pollen spectrum analysis, 26 samples classified as light by spectrophotometry (≤50 mm Pfund), along with six dark samples, were acetolised with adaptation of solution/rinsing with ethanol. Following that, the pollen residue was analysed under an optical microscope. The obtained data were subjected to ordination through a principal coordinate analysis and a detrended correspondence analysis. A total of 151 pollen types were identified in samples of light honeys, representing 41 botanical families, three of which are noteworthy: Euphorbiaceae, Fabaceae and Rubiaceae. Among the types present in 50% or more of the samples, and the highest relative frequency, the following are significant: Mimosa caesalpiniifolia, Mimosa pudica, Mimosa tenuiflora/verrucosa, Pityrocarpa moniliformis and Syagrus. Of the 26 analyzed samples of light honey, 13 were considered monofloral: seven of P. moniliformes, five of M. caesalpiniifolia and one of M. pudica. The ordering analysis revealed the existence of groups between light honeys, two of which are unrelated to dark honeys. Plants of the Fabaceae family, especially the genera Mimosa and Pityrocarpa, contribute greatly to the production of light honeys in Piauí State, Brazil.
Dactylofusa veliferaCocchio 1982 is an easily recognisable, fusiform Ordovician acritarch species with a characteristic membrane. The taxonomy of this taxon is revised based on a literature review and on the investigation of new fossil assemblages from sections in South China. Morphological and biometric studies show that a subdivision into three varieties is justified. The taxonomical rank of Dactylofusa velifera var. brevisAlbani 1989 is changed and its diagnosis is emended; Dactylofusa velifera var. velifera is the automatically created autonym. An additional new subspecific taxon is erected: Dactylofusa velifera var. sinensis var. nov. The stratigraphical and palaeogeographical occurrences of Dactylofusa velifera are reviewed, indicating that the species was widely distributed around the peri-Gondwanan margin during the Early Ordovician and early Middle Ordovician. Dactylofusa velifera is of biostratigraphical importance because its First Appearance Datum (FAD) can be used to indicate the late Tremadocian. Palaeobiogeographically, its distribution generally corresponds to that of the Early Ordovician ‘messaoudensis-trifidum’ acritarch assemblage in the peri-Gondwanan region.
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