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Methodological papers advise to collect moss surface samples either at the beginning or at the end of the flowering season. In reality, such collections occur often within the flowering season for purposes of vegetation description or because of accessibility of remote study areas. Here we test whether the season of moss surface sample collection has an influence on pollen spectra. Ten moss/litter samples were collected in different habitats of the natural reserve ‘Spasskaya Gora’ (Perm region, Russia) in July and September from the same locations exactly. The results show that pollen assemblages reflect well the present dominant vegetation of Pinus-Betula-forests and grasslands and demonstrate differences between open and forested areas as well as between abandoned fodder meadows and semi-natural hay meadows in use. Paired t-tests and Wilcoxon tests demonstrate that the dominant pollen taxa Pinus diploxylon-type, Betula and Poaceae as well as the rarefied number of pollen taxa do not differ significantly between seasons, while values of Artemisia are significantly higher in September. A significant decrease in pollen concentration in September indicates the importance of washing-out of pollen by precipitation. PCA results demonstrate the similarity of the pollen spectra between the seasons. Based on our results, we conclude that the season of surface sample collection does not significantly influence the pollen assemblages and appropriate field studies can be carried out in summer during the flowering season. However, we strongly recommend to collect bulk samples of mosses with basal parts and/or litter with surface soils in order to ensure representation of the average pollen signal for the previous years and to dilute local extremes in the pollen deposition.
This study focuses on five cores in and around three of the hundreds of shallow ephemeral hypersaline lakes distributed in chains along traces of ancient drainages that dominate the southern Western Australian landscape. Cores within and on the shore of Lake Aerodrome (LA1-09, LA2-09), Prado Lake (PL1-09, PL2-09), and Gastropod Lake (GLE1-09) in the Cowan Paleodrainage were drilled as part of a multidisciplinary study to understand the evolution of the lakes. Lithological and palynomorph data provide insights into the region's the depositional history, and floristic and climate evolution of the region. The nearly 60 m deep LA2-09 core provides the most comprehensive data. The basal ∼15 m interval of this core comprises two distinct lignite units with a clay interbed that preserve a rich palynomorph assemblage of the Werillup Formation. This assemblage is characterized by the first appearance datum (FAD) and last appearance datum (LAD) of key late Eocene taxa that correlate with the Middle Nothofagidies asperus Zone, and is indicative of freshwater swamp surrounded by subtropical to temperate rainforest. Above the upper lignite (except the topmost sample), evaporitic-siliciclastic units preserve a depauperate palynomorph assemblage comprising mostly long-ranging sclerophyllicxerophilous-halophilic taxa. The pollen Myrtaceidites lipsis constrains the age of the upper ∼23 m interval as Pliocene to Recent. This younger assemblage also preserves reworked palynomorphs from the Werillup Formation and older units, and is identified in the other four cores. The presence of the halophilic green alga Dunaliella in the younger assemblage is used as a proxy for aridity and hypersaline conditions during post-Eocene deposition in southern Western Australia. Its absence in the neutral-alkaline lake water and uppermost core samples of GLE1-09 is either due to predation by the acidophobic gastropod Coxiella residing in the lake, or the fact that the type of Dunaliella preserved in the core samples is acidophilic.
Bee bread samples from the hives of Tetragonula biroi managed in agricultural and agroforest sites in Nagcarlan, Laguna, Philippines were analyzed through light microscopy during the wet season from June to November. A total of 31 pollen types, belonging to 20 botanical families were identified as pollen sources of T. biroi. Adonidia merrilli Becc. and Cocos nucifera L. were consistent predominant pollen sources (>45%) in both sites. The other predominant pollen types in the agricultural site were Arecaceae type 1, Fabaceae type and Marantaceae type, and Ipomoea sp. in the agroforest site. A decreasing number of pollen types were observed from early to late wet months of the study period. Though both sites provide a wide array of pollen sources for T. biroi, the presence of long-blossoming crops resulted in the homogenization of pollen types in the hive. This study highlights the importance of crop diversity and surrounding natural vegetation in the agricultural landscape in providing various pollen sources for pollinators like T. biroi.
Cuphea section Trispermum, one of the 13 sections of the genus, predominantly composed of Brazilian species, underwent a new circumscription after morphological and molecular studies. The pollen morphology of classic representatives of the section and related taxa transferred to this section was investigated, based on light microscopy and scanning electron microscopy, to support the taxonomy and the new section circumscription. The analyzed species present pollen that is small to medium in size, isopolar, oblate, triangular to ovate-triangular, tricolporate, and syncolpate, with prominent pores and psilate exine, thickened between the pores in the mesocolpium. The results of this study confirm the palynological homogeneity of C. sect. Trispermum, and of the taxa transferred from other sections, which are unified by exine thickening in the region between the pores. These characteristics corroborate the monophyly of the section, according to molecular phylogenetic studies.
The pollen morphology of eight endemic species of the genus Inula L. (Asteraceae) – I. helenium subsp. orgyalis (Boiss.) Grierson, I. helenium subsp. vanensis Grierson, I. macrocephala Boiss. & Kotschy ex Boiss., I. discoidea Boiss., I. sarana Boiss., I. fragilis Boiss. & Hausskn., I. anatolica Boiss. and I. sechmenii Hartvig & Strid – distributed in Turkey was studied with light microscopy and scanning electron microscopy. We found that the pollen of these Inula taxa are prolate-spheroidal in shape (except in Inula discoidea), with the polar axis ranging from 19.18 to 33.14 µm and the equatorial diameter ranging from 18.54 to 32.92 µm. The pollen grains are tricolporate and their ornamentation is echinate. The exine thickness ranges from 0.87 to 2.07 µm. As this study demonstrates, results of Principal Component Analysis are revealed that some of the pollen characters, such as spine length and width, are significant morphological characters for taxonomic discrimination of the eight endemic Inula taxa. According to cluster analysis, two main groups of examined taxa are constituted.
The pollen morphology of 40 specimens of 15 species belonging to eight genera in the subfamily Salicornioideae (Chenopodiaceae) was studied using light and scanning electron microscopy to evaluate the taxonomic importance of pollen characters. Pollen grains were characteristically pantopolyporate, with 31–51 evenly distributed pores on the surface. The tectum and operculum are covered with minute spinules, typical of other members of the Chenopodiaceae, with minor differences among genera and species. Perforation was seen only in Halostachys belangeriana at high magnification. Pollen characters studied here include pollen and pore diameters, number and density of apertures, interporal distance (chord), chord/pollen diameter ratio, pore diameter/pollen diameter ratio and spinule density on the tectum and operculum. Despite extreme uniformity in pollen morphology, there is good evidence supporting currently known phylogenetic relationships and generic delimitations within the subfamily Salicornioideae. The significant differences in pollen characters among populations of Halostachys belangeriana and Halocnemum strobilaceum may indicate genetic diversity or polyploidy in different populations. The pollen characters provide limited taxonomic value in the subfamily Salicornioideae, which may come from habitat homogeneity of all species growing in hypersaline marshes and inland hygrohalophytic communities.
The family Passifloraceae sensu stricto occurs mainly in the Neotropical region. Four genera are represented in the American flora, Ancistrothyrsus Harms, Dilkea Mast. (restricted to the Amazon rainforest), Mitostemma Mast., and Passiflora L. The largest and most studied genus is Passiflora. The three other genera are considerably smaller; Ancistrothyrsus contains two species, Dilkea twelve, and Mitostemma three. This study aimed to perform a palynological characterization of six species belonging to the genera Ancistrothyrsus, Dilkea, and Mitostemma: Ancistrothyrsus tessmannii Harms, Dilkea johannesii Barb. Rodr., Dilkea retusa Mast., Mitostemma brevifilis Gontsch., Mitostemma glaziovii Mast., and Mitostemma jenmanii Mast. Pollen specimens were acetolyzed, measured, described, and photographed with light and scanning electron microscopes. Pollen grains are medium- or large-sized, prolate-spheroidal, 3-colporate in Ancistrothyrsus and Mitostemma and (3)4(5)-colporate in Dilkea. The sexine is thick, reticulate, muri sinuous or straight, simplicolumellate, with two nexine layers in some species. Pollen morphology is an important source of taxonomic information that allows distinguishing and identifying species of the genera Ancistrothyrsus, Dilkea, and Mitostemma, making it possible to draw comparisons with the genus Passiflora. The descriptions presented in this study contributes to the knowledge of the pollen flora of Passifloraceae.
This study presents the pollen morphology of 11 Brazilian native species and one variety of Caesalpinioideae and Detarioideae (Fabaceae) from forest patches of São Paulo, Brazil. The aim of this research is to expand the morphological knowledge of the species of these subfamilies, contributing to the taxonomic study and conservation of these species in the forest area. The pollen grains were acetolyzed, measured, described qualitatively and illustrated using light microscopy and scanning electron microscopy. Differences in pollen unit (tetrads or monads), size (small to large), amb (circular to triangular), shape (oblate to prolate), details of the polar area (very small to large), position of apertures (angulaperturate, planaperturate, subplanaperturate, or fossaperturate), type of endoapertures (lolongate, circular, or lalongate) and exine ornamentation (psilate, scabrate, microreticulate, or reticulate heterobrochate) aid in the differentiation of pollen grains of the analyzed species. In this study, the metric variables related to the apertures assist in the quantitative separation of the species (multivariate analysis), and these variables, together with the qualitative data, contribute to affirm the eurypalynous character of the subfamilies Caesalpinioideae and Detarioideae.
Palynological analysis of Site M0077A in the Chicxulub impact crater has yielded a record of the immediate Cretaceous/Paleogene (K/Pg) recovery from ground zero of the end-Cretaceous mass extinction, followed by a record of the Paleocene–Eocene Thermal Maximum (PETM) and later Ypresian (Eocene), including the Early Eocene Climatic Optimum (EECO). Eight specimens of the dinoflagellate cyst Trithyrodinium evittii have been observed near the base of the K/Pg transitional unit; these likely represent a post-impact dinoflagellate disaster recovery assemblage deposited within several days following the impact, although the possibility that some or all of the T. evittii specimens are reworked Maastrichtian cysts cannot be fully excluded. Despite high-resolution sampling of the lowermost Paleocene successions, the oldest identifiable terrestrial palynomorphs observed in the Site M0077A core, two specimens of Deltoidospora fern spores, occur at least ∼200,000 years after the impact. Other than these occurrences, the Paleocene section is nearly barren in terms of palynomorphs, likely a result of poor preservation of organic material combined with a long recovery time for vegetation in the vicinity of the crater. Pollen and fungal spore concentrations spike in an anoxic dark shale deposited during the PETM around 56 Ma, with a diverse pollen assemblage indicating the presence of a coastal shrubby tropical forest in the geographic vicinity, likely in the Yucatán Peninsula to the south. In the marine realm, this interval is characterized by thermophilic assemblages of dinoflagellate cysts. Stratigraphically constrained cluster analysis identified four statistically robust sample clusters in the lower Eocene successions, with Malvacipollis spp. and Milfordia spp. abundances driving the highest average dissimilarity between clusters. A second notable spike in palynological concentrations above the PETM section may represent another early Eocene hyperthermal event. Pollen and plant spore concentrations generally increased during the EECO, associated with increases in terrestrial input during basin infilling.
The Pin Formation of the northern Indian Himalaya may contain a record of the late Katian (Late Ordovician) warming event (the Boda Event). Palynological samples collected from two members of this formation are investigated in order to evaluate the biostratigraphical potential of the different microfossil groups. Acritarchs and chitinozoans are the most abundant microfossils, but fragments of scolecodonts and melanosclerites are also present. Several of the acritarchs from the Pin Formation are long-ranging through the lower Palaeozoic, but other taxa can be compared to Upper Ordovician (Katian) assemblages described from other parts of the world. The chitinozoan assemblages, consisting of 13 species (including those in open nomenclature) belonging to seven genera, are mainly recorded from two layers. The chitinozoan assemblage collected from the sample at 87.3 m in the uppermost part of the Farka Muth Member, and that collected at 184.89 m from the Takche Member, indicate a late Katian age. This age interpretation is in accordance with conodont data from the Takche Member, a positive carbon isotopic peak from the top of a shale unit in the Takche Member, and the initial part of the rapid negative shift of the Paroveja isotopic excursion related to the Boda Event of late Katian age. Further detailed studies with a higher number of samples are needed, that describe better preserved and more diversified palynomorph assemblages, which would help to more precisely refine the Upper Ordovician biostratigraphy in this area.
The palynoflora and organic petrography of core samples from the Tyler Formation in the Williston Basin, North Dakota, USA were evaluated to determine their age and depositional environment. The palynofloras are assigned to seven plant groups used by previous authors who studied Carboniferous floras. Lycopsid trees, represented by Lycospora species and Crassispora kosankei are the most abundant and well-preserved miospores recorded. Palynomorphs representing small lycopsids, calamites, cordaites, and conifers, comprise a relatively minor part of the palynoflora. The petrographic component from seven coeval coal samples contain moderate to high mineral content and macerals which are dominated by vitrinite (woody components) and to a lesser extent inertinite and liptinite (lipid-rich plant material). Common vitrinite macerals include collotelinite and collodetrinite, and semifusinite and minor fusinite representing inertinite macerals. The palynofloras are of Early Pennsylvanian age, based on the presence of the age-significant fossils Schulzospora rara and Cirratriradites saturnii together with abundant Lycospora spp. The palynoflora and petrographic data suggest that the Tyler Formation in this location was deposited in a fluvially-dominated delta with some tidal influence. Wet, stagnant anoxic environments (coal swamps) were frequently flooded with clastic material from a fluvial source. Macerals, especially inertinite, imply periods of subaerial exposure, fire, or highly oxygenated waters, and liptinite (lipid-rich plant material), suggests periodic drowning of the coal swamp and formation of shallow lacustrine paleoenvironments.
The Cenozoic of the North Sea is among the best-documented stratigraphical successions in the world, and multiple palynological events have been recognised for chronostratigraphical control across the region. The ever-increasing number of wells studied for hydrocarbon exploration and production results in the generation of new biostratigraphical data that constantly increase our palynological knowledge of the area. Here we describe two new dinoflagellate cyst species from an Lower Eocene (Ypresian) to Lower Oligocene (Rupelian) succession in Gannet Field (UK Central North Sea). These are Reticulatosphaera valdereticulata sp. nov., a short-lived Rupelian index taxon, and Alisocysta heilmannii sp. nov., previously informally known as Alisocysta sp. 2, which is an Ypresian marker widely used by biostratigraphers working the North Sea region. The development of a dense network of trabeculae connecting the processes distally allows Reticulatosphaera valdereticulata sp. nov. to be clearly distinguished from the closely similar Reticulatosphaera actinocoronata. The main diagnostic feature in Alisocysta heilmannii sp. nov. is the development of delicate penitabular septa. Both species show widespread palaeogeographical distribution across the North Sea region. We also document the diverse palynofloras in which the two new species are encountered and discuss biostratigraphical application and palaeoenvironmental settings.
Diverse and well-preserved marine palynomorphs occur in the Padeha, Khoshyeilagh, and Mobarak formations in the Khoshyeilagh area, northeastern Alborz, northern Iran. The marine palynomorph assemblages consist of acritarchs, prasinophytes, and chitinozoans, comprising 27 genera and 46 species. In addition, the studied sediments contain 20 species of algae, foraminifera, and corals allocated to 11 genera. The vertical distribution of acritarchs and chitinozoans allows the erection within these sediments of three local assemblage zones. Biozone I occurs in the upper part of the Padeha Formation and the basal part of the Khoshyeilagh Formation, suggesting a Frasnian–early Famennian age; Biozone II is present in the Khoshyeilagh Formation and indicates a Famennian age. Biozone III, which occurs in the basal part of the Mobarak Formation, suggests a Tournaisian age for this interval. Many of the palynomorph species, such as Crassiangulina tessellita, Daillydium pentaster, Deltotosoma intonsum, Gorgonisphaeridium discissum, Helosphaeridium microclavatum, Horologinella horologia, Papulogabata annulata, Somphophragma miscellum, and Veryhachium downiei, are closely comparable with coeval assemblages recorded from Australia, Ireland, Portugal, Saudi Arabia, North Africa, South America, and North America. This indicates the close relationship of the Iranian Platform to other parts of the northern Gondwana and southern Laurentian domain during the Late Devonian–Early Carboniferous. Moreover, results of similarity indices of marine microphytoplankton indicate a relatively high degree of similarity between the assemblages of the Khoshyeilagh area and those elsewhere in the Alborz Mountains and the Kerman Basin. Palaeontological evidence indicates that the Khoshyeilagh Formation was deposited in a low-energy, somewhat offshore, normal marine environment within the Alborz Basin, along the Palaeo-Tethys Ocean during this time interval. Furthermore, based on palynological data gathered from Iran, it can be concluded that Iran was an island during this interval of time.
The Devonian strata in the Western Desert of Egypt contain diverse plant and animal remains, in addition to the commonly reported miospores, acritarchs and chitinozoans. These remains are of significant paleoenvironmental and biostratigraphic value. This is the first study dedicated to recording these assemblages in the Devonian section in the Sifa-1X well. The zooclast assemblage described herein consists mainly of scolecodonts and remains of arthropods, notably eurypterids, arachnids and scorpions. The recovered scolecodonts belong to several species and likely three different families. The eurypterids are represented by several spines and exoskeleton cuticles. The shape and dimensions of the spines are analyzed and described. The spines vary in shape and size. A fragment of the arachnid Attercopus fimbriunguis was found in the Early Devonian. Additionally, fragments of scorpions were recovered, including pedipalp manus fragments of Compsoscorpius elegans and Corniops mapesii. The phytoclasts contain nematophytal cuticles and early plant tracheids. Some other fragments bear stomata and are attributed to the lycopsid Drepanophycus spinaeformis and the zosterophyllopsid Forania plegiospinosa. The nematophytes are represented by Nematothallus and Cosmochlaina cuticles and other tubular elements such as Porcatitubulus annulatus, Porcatitubulus spiralis, Constrictitubulus cristatus, Laevitubulus, Ornatifilum lornensis and Ornatifilum granulatum.
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