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Staurosaccites, a highly distinctive pollen genus, ranges from the late Anisian (Pelsonian; Middle Triassic) to the Norian, at low to mid latitudes, globally. Here we review the systematic taxonomy and spatial and temporal ranges of Staurosaccites. We provide an emendation to S. tharipatharensis, synonymise S. minutus with the type species S. quadrifidus, and retain the species S. quadrifidus, S. tharipatharensis, S. densus and S. marginalis. Following comparison with morphologically similar pollen and environmental reconstructions of the habitat of its parent plant, we hypothesise that Staurosaccites was produced by a conifer that was likely adapted to warm and humid conditions. Based on occurrences of diagnostic taxa for the Onslow and Ipswich microfloral provinces in the Southern Hemisphere (Staurosaccites, Camerosporites, Enzonalasporites, Infernopollenites and Ovalipollis), we show that these palynofloras were established in the Middle Triassic. Our findings further suggest that, based on the presence of diagnostic taxa in western Laurasia and their absence in eastern Laurasia, western and eastern Laurasia represent different palynofloral provinces in the Middle Triassic. [ABSTRACT FROM AUTHOR]

To characterise the botanical and geographical origin of honey from the Chaco region (Argentina), 189 samples of honey were examined for pollen content using standard methodology. A general feature was the high representation of pollen from native arboreal plants, mainly of Fabaceae and the scarcity of pollen from herbaceous plants. One hundred and twenty-three samples proved to be unifloral. The most common were from:Prosopis alba,Helianthus annuus,Sarcomphalus mistol,Eugenia unifloraandSchinopsis balansaefollowed by those ofCopernicia alba,Trithrinax schizophylla,Tessaria integrifolia,Baccharis-Eupatorium,Cynophalla retusa,Schinopsis lorentzii,Gleditsia amorphoides,Heimia salicifolia,Pisonia zapallo,Sagittaria montevidensisandBulnesia sarmientoi. The pollen spectrum allowed the Dry and Humid Chaco ecoregions to be distinguished. The presence of pollen from cultivated crops and naturalised plants reflects a transitional complex between both ecoregions. [ABSTRACT FROM PUBLISHER]

Propolis quality depends on its botanical origin and the producing bee species. Twenty-one propolis samples from northeast, southeast and southern Brazil were investigated using palynological and physicochemical techniques. The aim of the present study was to understand Artepillin-C concentration in the propolis samples in relation to the pollen spectrum and its phytogeographical origin. The propolis obtained fromBaccharis(Asteraceae), occurring mainly in mountain regions of the southern part of the state of Minas Gerais to the northern part of the state of Paraná, presents a high content of Artepillin-C and is the most valuable. Nevertheless, Artepillin-C was detected in the propolis samples from localities whereBaccharisplants are growing. It is expected that other plant species of the Asteraceae family, such asEupatorium, may contribute to the production of propolis containing a high content of flavonoids. [ABSTRACT FROM AUTHOR]

The pollen spectra of 16 samples of geopropolis ofMelipona fasciculatafrom three phytogeographic regions in Maranhão, Brazil, have been analysed. Samples GP1 to GP4 were collected in Palmeirândia located in the region of periodic flooded fields (lowlands of the northern micro-region of Maranhão). Samples GP5 to GP8 were collected in Barreirinhas (Cerrado vegetation, northern micro-region of Maranhão). Samples GP9 to GP16 were collected in Belagua (Restinga vegetation, eastern micro-region of Maranhão). Thirty-eight pollen types were identified, distributed in 26 families and 29 genera. The most frequent pollen types wereMimosa pudica,Mimosa caesalpiniifolia,ChamaecristaandSolanum.Eucalyptus,Psidium,Combretum/Melastomataceae, Arecaceae,MauritiaandArdisiapollen types were present in variable amounts (‘accessory pollen’ and/or ‘isolated pollen’).Alternanthera, Amaranthaceae,Desmodium,DiocleaandDalbergiapollen types occurred with a lower percentage (‘occasional pollen’). The first two axes of the principal component analysis grouped 69% of the pollen variability of samples from three locations. Even though all three ecosystem samples were collected in the same month, they had different patterns of similarity. The qualitative and quantitative analyses of pollen types in geopropolis samples ofMelipona fasciculatawere phytogeographically valuable for characterising the samples and providing knowledge about the flora in the Brazilian state of Maranhão. [ABSTRACT FROM AUTHOR]

Anacolosidites Cookson & Pike, a fossil pollen genus recorded since the Campanian, is peculiar in its morphology – six-porate with three apertures on each hemisphere, located away from the equator, and with the distal and proximal apertures positioned over each other. Representatives of this fossil genus are widely considered to represent extant Olacaceae from tribe Anacoloseae. Olacaceae is an exclusively tropical angiosperm family with a pantropical distribution; consequently the fossils are often used to suggest a tropical climate and in addition are frequently used as a stratigraphic marker. Fossil species assigned to Anacolosidites are quite variable and may not all represent Olacaceae, in which case they may not indicate tropical climate. The present study is a morphological survey of fossil pollen assigned to Anacolosidites ; it identifies the published reports of the fossil species that probably represent positive occurrences of Olacaceae pollen in the fossil record. Within Olacaceae, Anacolosidites -type pollen is usually compared with pollen of genera in tribe Anacoloseae, in particular: Cathedra , Anacolosa and Phanerodiscus , but never with the pollen of Ptychopetalum , a genus from tribe Olaceae with closely similar pollen to the other three genera, but with a reticulate tectum and very small circular apertures located near the equator. Nevertheless, the records of reticulate Anacolosidites species which have been excluded from the emended diagnosis are unlikely to be related to Ptychopetalum . The earliest accepted record of Anacolosidites is from the Late Cretaceous (Maastrichtian) of Germany. However, most Late Cretaceous records, and later Russian and Chinese occurrences referred to Anacolosidites , consist mainly of Normapolles-type pollen, whereas many of the Cenozoic records assigned to Anacolosidites have a much clearer affinity with the pollen of Anacolosa , Cathedra and Phanerodiscus (tribe Anacoloseae). The newly emended genus Anacolosidites may be used as a stratigraphic marker for tropical or megathermal climatic conditions. [ABSTRACT FROM AUTHOR]

A morphological study of dispersed Circumpolles pollen grains from the Upper Triassic of the Southern Alps has been initiated with the genus Duplicisporites . Individual pollen grains were studied by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Seen with SEM the pollen surface is finely verrucate with low verrucae of different sizes. A sub-equatorial continuous rimula is clearly visible. The proximal trilete scar is small and indistinct. TEM images reveal a bi-layered exine. The ectexine is formed by numerous small, closely packed, granulae subdivided by irregularly-spaced cavities. In the region of the subequatorial canal, the ectexine becomes thinner, about 1/3 of the usual thickness. At places, the ectexine is slightly separated from the underlying endexine. The endexine is prominent and significantly darker than the ectexine. It is homogeneous and of constant thickness. On the basis of its older age, with respect to Classopollis , the present ultrastructural dataset provides information on the possible origin of cheirolepidiaceous-type morphology. [ABSTRACT FROM AUTHOR]

Stellate pore ornamentation is an unusual feature of angiosperm pollen, so far it is known in only ten genera of Amaranthaceae. The pollen grains of these plants have apertures with large hook-shaped ektexinous bodies that are stellately arranged. Previous studies interpreted this character complex as a synapomorphy in consideration of its strong specialization. By reconstructing the evolution of stellate pore ornamentation based on phylogenetic trees of Amaranthaceae obtained by parsimony, likelihood, and Bayesian analysis of chloroplast trnK/matK DNA sequences, clear evidence is provided for several independent origins and reversals to less specialized aperture types. In addition to the gomphrenoid genus Pseudoplantago , stellate pore ornamentation evolved several times among achyranthoid genera, which have an African distribution. The most derived apertures, with 5 – 6 large protruding hooks, appear independently in Centemopsis on the one hand, and in Psilotrichum sericeum on the other. In an effort to break down the complex character syndrome of stellate pore ornamentation, we delimited a set of six pollen morphological characters that could be independently traced on the phylogeny. It appears that stellate pore ornamentation was independently derived from apertures with equally spread ektexinous bodies that became hook-shaped, reduced in number, and symmetrically arranged. Likewise the symmetrically arranged, rectangular ektexinous bodies in Marcelliopsis represent an independent specialization. In view of this pattern of morphological changes, functional significance in the context of specialized insect pollination syndromes and positive selection for stellate pore ornamentation is hypothesized. Stellate pore ornamentation provides an example of a specialized pollen character complex with adaptive significance, and underlines the need for a dense taxon sampling for analyses of character evolution. [ABSTRACT FROM AUTHOR]

The article discusses the late glacial and holocene vegetation development of the raised bog Fláje-Kiefern, which lies in the Krušné Hory Mountains in Czech Republic. The phytogeographic region of the mountains is described as a region of mountain flora and vegetation, with thermophilus species largely missing. Conifers prevail in the natural forests. The mountains' bedrock is Precambrian crystallinicum.