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Previous studies on Abolboda pollen did not conduct statistical analyses of morphological data. Here, the pollen morphology of four Brazilian species and three varieties, represented by 13 herbarium specimens, is described. Pollen grains were treated by 60% lactic acetolysis, measured and photographed under light and scanning electron microscopy. A multivariate analysis was performed for the first time to find possible features that aid the specific and infraspecific delimitation within this genus. Abolboda is characterised by pollen grains in monads that are spheroidal, large to very large sized (59.9 µm [A. abbreviata] to 158.9 µm [A. pulchella]), inaperturate and atectate. The nexine is very thick. The spine shape and the width of its base have been considered specific and infraspecific diagnostic features; however, at present, they are not considered consistent characters with a systematic value. The combination of pollen size, nexine thickness, and dimensions of the sexine excrescences ('inverted funnelform shaped' spines, 'obconical shaped' spines, and baculum-like, pilum-like or verruca-like elements) are the most important characteristics at the species level and for grouping the varieties. This study presents informative morphological data useful for future phylogenetic optimisation and contributes to the systematics of the Abolboda genus. [ABSTRACT FROM AUTHOR]

The article introduces various reports published within the issue, including one by Stefan Vinckier, Pascal Cadot and Erik Smets on the description of orbicules in the order Gentianales and another by Madeline M. Harley, Unsook Song and Hannah I. Banks on pollen morphology and systematics of Burseraceae.

This study focuses on the pollen season timing and intensity, and the influence of weather conditions, on airborne Cupressaceae, Quercus, and Poaceae pollen in two different biogeographical areas, Córdoba (Spain) and Tulsa, Oklahoma (USA), during 2010–2014. Pollen concentrations were recorded using Hirst-type spore traps. The meteorological parameters studied included temperature, relative humidity, wind speed, and rainfall. This study aims to define the pollen seasons and their intensity and relationships with meteorological parameters in different biogeographical areas. The main pollen season (MPS) of each pollen type was divided into two periods: pre-peak and post-peak. The Shapiro–Wilk normality test was applied to the pollen concentrations and log transformed data were used. Pearson correlations and linear regression were applied for the pre-peak, post-peak, and MPS for comparing pollen concentrations with meteorological parameters considering both the same day and the previous day. Then, multiple regression analysis was applied with all the meteorological parameters that showed significant results in the linear regression. The models were validated through correlations between the measured and predicted pollen concentrations. The results showed a small difference in the MPS for the different pollen types at each site. Temperature, relative humidity, and rainfall influenced the pollen concentrations. The same day's meteorological parameters usually had a greater impact on the pollen concentration than the previous day's meteorological parameters; although, pollen concentrations for the next day could be forecasted considering the meteorological parameters forecasted for the present day. The pollen concentrations showed greater correlations with temperature. [ABSTRACT FROM AUTHOR]

Misodendraceae is a small family of mistletoes in the order Santalales. Its distribution is restricted to the southern South American temperate forests. The family comprises the sole genus Misodendrum with eight species of hemiparasitic shrubs, mainly parasitising the southern beech Nothofagus. This contribution presents palynological evidence from seven species, using light microscopy and scanning electron microscopy. Pollen grains are consistently small, periporate and echinate, although differences in the length of echini and number and size of pores were noted. Pollen features can be used to distinguish groups of species and, in some cases, individual species. Cluster analysis of pollen characters differentiates two main groups: one includes M. brachystachyum, M. oblongifolium and M. quadriflorum; and the other includes M. gayanum, M. linearifolium, M. punctulatum and M. angulatum. Palynological results are compared with previous systematic studies of the family. The South American fossil pollen record is summarised and characters of the fossil pollen are analysed using UPGMA to test the relationships between extant and fossil species. Miocene pollen resulted similar to species of subgenus Angelopogon while Eocene pollen is disimilar to extant species of Misodendraceae. [ABSTRACT FROM AUTHOR]

An obituary for Norwegian botanist Svein B. Manum is presented.

The important marker species for the base of the Jurassic, Cerebropollenites thiergartii, occurs contemporaneously with at least nine related taxa. However, their distinction is difficult and has been confused in the past. In addition, a long history of numerous recombinations with different genus names (e.g. Tsugaepollenites and Sciadopityspollenites), and inconsistent classifications or synonymisations, further complicate the taxonomic framework of Cerebropollenites thiergartii. A comprehensive study of these ten taxa, summarising their crucial distinctive characteristics and potential synonymy, is currently missing. This limits the stratigraphic value of Cerebropollenites thiergartii and associated taxa relevant to the Triassic–Jurassic transition. Here, we revisit relevant holotype material, related taxa and investigated new material for potential interspecific and intraspecific morphological variation. Based on an empirical analysis of name use and an extensive literature review, we identified previous sources of confusion, re-evaluated the distinctive characteristics and stratigraphic value of these taxa, and their relevance for the Triassic–Jurassic transition. Finally, we argue that the recombination as Sciadopityspollenites thiergartii is taxonomically and nomenclaturally imperative, not only due to priority, but also because it unifies previous disjunct use of Cerebropollenites for Mesozoic and Sciadopityspollenites for Cenozoic taxa, or Mesozoic species in many Russian studies. Thus, we propose a series of nomenclatural novelties: Sciadopityspollenites emend., Sciadopityspollenites thiergartii comb. nov. et emend., S. thiergartii ssp. nov. thiergartii, S. thiergartii ssp. multiverrucosus stat. nov., S. megaorbicularius sp. nov., S. carlylensis comb. nov. et emend., S. serratus emend., S. macroverrucosus emend., S. mesozoicus emend., Cryptopalynites gen. nov., Cryptopalynites pseudomassulae comb. nov. et emend. [ABSTRACT FROM AUTHOR]

The pollen morphology of 150 species representing 33 genera of Zingiberaceae was examined using light (LM) and scanning electron microscopy (SEM) as part of a comprehensive survey of this family. The pollen grains of the species studied are inaperturate, with a thin exine and thick intine, and with diverse ornamentation. This variation in the pollen suggests it may be a useful source of characters for future phylogenetic analyses based on combined datasets. [ABSTRACT FROM AUTHOR]

The incidence of fungi inside certain historic buildings and premises used for storing heritage collections in Havana (Cuba) and fungal contamination of the items stored there have been assessed. Cultivable airborne fungi were sampled using the slit-to-agar impaction method with a type S Chirana aeroscope; various substrates were swab-sampled in addition. Most common were Aspergillus, Penicillium and Cladosporium. The physiological features of some of the fungal strains isolated from the substrates were examined in order to evaluate their potential for biodeterioration. Numerous Aspergillus strains were able to produce cellulase and acids and to hydrolyse gelatine, while Cladosporium displayed the greatest ability to produce polyphenol oxidases. One third of the strains tested, all belonging to the genera Aspergillus and Penicillium, produced pigments. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue including one about the European Pollen Database.

Simultaneous microsporogenesis is described for the first time in a grass, Streptochaeta spicata Schrad., a tropical Brazilian species that belongs in the early-divergent subfamily Anomochlooideae. Microsporogenesis is successive in all other Poaceae examined so far, and most other members of the order Poales, to which grasses belong. The only other reports of simultaneous microsporogenesis in Poales are in Rapateaceae and some members of the cyperid clade (Juncaceae, Cyperaceae, Prionium and Thurnia). Among the graminids, Ecdeiocolea (the putative closest relative to Poaceae) is successive, as are Joinvillea, Flagellaria and all other Poaceae, indicating that the simultaneous condition is autapomorphic in Streptochaeta, though Anomochloa has yet to be examined. Anther wall development in Streptochaeta is of the reduced type, as also in another early-divergent grass Pharus, though most other Poales, including most grasses, have the monocot type. In Streptochaeta, as in Pharus, the endothecium lacks thickenings, unlike other grasses that have a persistent endothecium with thickenings. The centrifixed anthers and nonplumose stigmas of Streptochaeta suggest entomophily. [ABSTRACT FROM AUTHOR]

Triprojectacites Mtchedlishvili, 1961 emend. Stanley 1970 is an important pollen group of the Northern Hemisphere palynofloras during the Late Cretaceous. It is featured by three, or occasionally four or five, projections at the equatorial zone of the body with colpate apertures and endexinous thickenings. This pollen group is very useful in the stratigraphic division and correlation for its high diversity, short stratigraphic interval, and rapid evolution. However, the diversity and complex morphology make the pollen difficult to describe and classify, which brought discrepancies in the understanding and application of genus and species. In the present article, we make a re-evaluation of the previously proposed genera by using an improved, clearly defined morphological terminology based on standardised measurements. Finally, eight genera are screened out to set a new classification system from the 39 genera that have been proposed in relation with Triprojectacites. A diagnostic key is compiled for the convenience of differentiating them. [ABSTRACT FROM AUTHOR]

Records of Poaceae pollen concentration from three years of sampling in a rural area of West Wales have revealed distinctive circadian patterns of variation. Maximum pollen concentrations are typically recorded between 14.00 and 16.00 hours, on days both above and below an average daily Poaceae pollen count of 50 grains m[sup -3], although later peaks in concentration may be recorded during periods with no precipitation. Variations in the periodicity of Poaceae pollen are analysed in relation to meteorological conditions, phenological patterns of pollen release, pollen source area, and the magnitude of the average daily pollen count. The time of peak pollen concentration in West Wales is generally earlier than in other studies and this is explained by this study being conducted closer to Poaceae pollen source areas than most urban-based studies. [ABSTRACT FROM AUTHOR]

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]

The present study describes the floral morphology and evaluates pollen viability for the bromeliad Nidularium minutum Mez. during the flowering period 2018‒2019 through histochemistry and pollen germination tests. The inflorescences are nidular, capituliform with short branches bearing two to three odourless, bisexual and greenish-white flowers and with an androecium shorter than the gynoecium, consisting of six stamens with anthers featuring rimose dehiscence. The ovules are anatropous, displaying a small appendage in the chalazal region. The first flower opened in late November 2018 and flowering peak was in January 2019. Anthesis started at 6:55 a.m. and lasted until 8:49 a.m. Pollen/ovule ratio indicates facultative autogamy. The pollen grains are monads, medium to large, 2-(3)-porate, reticulate heterobrochate with abundant pollenkitt. A high frequency of unviable pollen grains with discrepant sizes was observed. The mature pollen grain is considered recalcitrant and therefore sensitive to desiccation. In vitro pollen germination after 48 hours was higher in BKM medium (64.77%) compared to SM (38.51%). Pollen viability was overestimated in all histochemistry tests, with Alexander (72.46%) being the closest to the in vitro germination rate. The results obtained for N. minutum bring new information about its floral biology as a subsidy to the cultivation of ornamental bromeliads that are at risk of extinction. [ABSTRACT FROM AUTHOR]