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Multicopy nuclear ribosomal DNA (rDNA) genes have been used as markers for fungal identification for three decades. The rDNA sequences in a genome are thought to be homogeneous due to concerted evolution. However, intragenomic variation of rDNA sequences has recently been observed in many fungi, which may make fungal identification and species abundance estimation based on these loci problematic. Ceraceosorusis an enigmatic genus in the smut lineage Ustilaginomycotinafor which very limited distribution data exist. Our previous research demonstrated intragenomic variation in the internal transcribed spacer (ITS1-5.8S-ITS2) region of two Ceraceosorusspecies. In this study, we described the fourth known species of Ceraceosorus, C. americanus, isolated from an asymptomatic rosemary leaf collected in Louisiana, USA. This is the first report of this genus in the Americas. We then selected all four known Ceraceosorusspecies, plus exemplar smut fungi representing all major lineages of subphylum Ustilaginomycotina, to examine sequence heterogeneity in three regions of the rDNA repeat (partial 18S, ITS, and partial 28S regions). Three methods were used: PCR-cloning-Sanger sequencing, targeted amplicon high-throughput sequencing, and whole-genome shotgun high-throughput sequencing. Our results show that Ceraceosorusis the only sampled fungal genus in Ustilaginomycotinawith significant intragenomic variation at the ITS, with up to 25 nucleotide variant sites in the ITS1–5.8S–ITS2 region and 2.6% divergence among analyzed ITS haplotypes. We found many conflicting patterns across the three detection methods, with up to 27 conflicting variant sites recorded from a single individual. At least 40% of the conflicting patterns are possibly due to PCR-cloning-sequencing errors, as the corresponding variant sites were not observed in the other detection methods. Based on our data and the literature, we evaluated the characteristics and advantages/disadvantages of each detection method. Finally, a model for how intragenomic variation in the rDNA copies within a genome may arise is presented.

ABSTRACTWe examined three arbuscular mycorrhizal fungi (AMF; phylum Glomeromycota) producing glomoid spores. The mode of formation and morphology of these spores suggested that they represent undescribed species in the genus Rhizoglomusof the family Glomeraceae. Subsequent morphological studies of the spores and molecular phylogenetic analyses of sequences of the nuc rDNA small subunit (18S), internal transcribed spacer (ITS1-5.8S-ITS2 = ITS), and large subunit (28S) region (= 18S-ITS-28S) confirmed the suggestion and indicated that the fungi strongly differ from all previously described Rhizoglomusspecies with known DNA barcodes. Consequently, the fungi were described here as new species: R. dalpeae, R. maiae, and R. silesianum. Two of these species lived hypogeously in the field in habitats subjected to strong environmental stresses. Rhizoglomus dalpeaeoriginated from an inselberg located within Guineo-Sudanian transition savanna zone in Benin, West Africa, where the temperature of the inselberg rock during a 5-mo drought ranges from 40 to 60 C. Rhizoglomus silesianumoriginated from a coal mine spoil heap in Poland, whose substrate is extremely poor in nutrients, has unfavorable texture, and may heat up to 50 C. By contrast, R. maiaewas found in more favorable habitat conditions. It produced an epigeous cluster of spores among shrubs growing in a tropical humid reserve in Brazil. Moreover, the compatibility of phylogenies of species of the family Glomeraceae reconstructed from analyses of sequences of 18S-ITS-28S and the largest subunit of RNA polymerase II (RPB1) gene was discussed.

Innovative structured catalyst supports, like solid foams, wire gauzes, and short-channel structures, are considered in methane catalytic combustion. For comparison, classical supports such as packed beds and monoliths are also taken into account. Moreover, two catalysts, displaying “fast” and “slow” kinetics, are examined. The performance efficiency criterion is applied to account for a balance between the process conversion, mass transfer, and flow resistance. Another “technological” approach compares reactor length and the corresponding pressure drop required to reach the desired conversion rate. Results indicate that wire gauze, solid foam, and short-channel structure are highly promising catalyst supports due to their intense heat/mass transfer and moderate flow resistance, particularly for fast catalytic reactions. For slow reactions, monoliths seem to be the best as they exhibit the lowest flow resistance.

Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11thInternational Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.

ABSTRACTThe anther smuts of the genus Microbotryumare known from host plant species belonging to the Caryophyllaceae, Dipsacaceae, Lamiaceae, Lentibulariaceae, Montiaceae, and Primulaceae. Of these, the anther smuts on Caryophyllaceae, in particular on Silenespp., are best known because they include model organisms studied in many disciplines of fungal biology. For Microbotryumspecies parasitic on Caryophyllaceae, a high degree of host specificity was revealed and several cryptic species were described. In contrast, the host specificity within Microbotryum pinguiculaeoccurring in anthers of different Pinguiculaspecies (Lentibulariaceae) has not been investigated in detail until now. The anther smuts on Pinguicula alpina, P. villosa, and P. vulgaris, on which M. pinguiculaewas described, were analyzed using nuc rDNA ITS1-5.8S-ITS2 and nuc rDNA 28S D1–D2 sequences and morphology to determine if they belong to one polyphagous species or rather represent three host-specific species. The results of the morphological investigations revealed no decisive differences between the anther smuts on different Pinguiculaspecies. However, genetic divergence and molecular phylogenetic analyses, which split the specimens according to host plant species, supported host specificity of the anther smuts on different Pinguiculaspecies. Accordingly, in addition to Microbotryum pinguiculaes. str. on Pinguicula vulgaris, M. alpinumsp. nov. on P. alpinafrom Europe and M. liroisp. nov. on P. villosafrom Asia are described and illustrated.

Anther smuts on Silene acaulisand S. uniflorafrom the Outer Hebrides, Scotland, UK), are analysed using morphological and molecular techniques, and found to represent Microbotryum silenes-acaulisand M. silenes-inflatae, respectively. This is the frst identifcation of caryophyllaceous anther smuts in the Outer Hebrides according to modern species concepts and the frst report of Microbotryum silenes-acaulisconfrmed by molecular analysis from the British Isles. Additionally, the genetic structure of Microbotryum silenes- acaulis, based on all currently available ITS sequences, is analysed and discussed. Seven ITS genotypes are determined for Microbotryum silenes-acaulis, including three genotypes in North America and four genotypes in Europe. Compared to European accessions, all North American accessions share specifc nucleotides and are genetically divergent.

ABSTRACTWhite leaf smut is a minor foliar disease of sunflower (Helianthus annuus) in the United States. The disease occurs primarily in greenhouse-grown sunflowers in California and causes leaf spot, defoliation, and a reduction in yield and crop value. Historically, many Entylomaspecimens with similar morphological characters, but infecting diverse plant genera including Helianthus, were called Entyloma polysporum. Recent comparative morphological and molecular work has shown that Entylomaspecies infect hosts within a single genus or species, suggesting that the sunflower Entylomaspecies may not be E. polysporum. In 2015, sunflower leaf smut material was collected from ornamental sunflowers in a greenhouse in Santa Barbara County, California. Morphologically, this species differed from E. polysporumin having smaller, more regular-shaped teliospores and prominently developed conidiophores with cylindrical conidia. The rDNA ITS1-5.8S-ITS2 (internal transcribed spacer [ITS]) region of the sunflower leaf smut was phylogenetically distinct from all previously sequenced Entylomaspecies and found only on H. annuus. This study confirms that the sunflower leaf smut pathogen represents a novel species, Entyloma helianthi. Possible misidentification of the anamorphic stage of Entyloma helianthias another leaf spot pathogen, Ramularia helianthi, is also discussed.

The recently described fungal phylum Entorrhizomycotawas established solely for the genus Entorrhiza, species of which cause root-galls in Cyperaceaeand Juncaceae. Talbotiomyces calosporus (incertae sedis)shares morphological characteristics and an ecological niche with species of Entorrhiza. We investigated the higher classification of T. calosporusto determine whether it belongs in Entorrhizomycota. Ribosomal DNA sequences showed Talbotiomyces tobe a close relative of Entorrhizaand both taxa form a highly supported monophyletic group. Based on molecular phylogenetic analyses and in congruence with existing morphological and ecological data, Entorrhizaand Talbotiomycesrepresent a deep dichotomy within the Entorrhizomycota. While species of Entorrhizaare characterised by dolipores and occur on monocotyledons, members of Talbotiomycesare characterised by simple pores and are associated with eudicotyledons. This expands the host range of the recently described Entorrhizomycotafrom Poales toother angiosperms. Higher taxa, namely Talbotiomycet alesord. nov. and Talbotiomycetaceaefam. nov., are proposed here to accommodate Talbotiomyces.

Cintractia carpophilavar. kenaica, a neglected taxon described from Alaska more than half a century ago, is re-described and illustrated. Its nomenclature and taxonomic status are discussed. This smut species is characterised by small spores with a very finely verruculose surface rarely enclosed by a thin, hyaline, mucilaginous sheath, a wall with 2–5 distinct internal swellings, and parasitism on Carex micropoda (Carexsect. Dornera).It is reallocated to the genus Anthracoideaas a distinct species, Anthracoidea kenaicacomb. nov, and assigned to Anthracoideasection Leiosporaewhich includes species having smooth or very finely verruculose spores. Morphological and biological characteristics of the five most similar Anthracoideaspecies are contrasted and discussed.

Currently, the monophyletic lineage of anther smuts on Caryophyllaceaeincludes 22 species classified in the genus Microbotryum.They are model organisms studied in many disciplines of fungal biology. A molecular phylogenetic approach was used to resolve species boundaries within the caryophyllaceous anther smuts, as species delimitation based solely on phenotypic characters was problematic. Several cryptic species were found amongst the anther smuts on Caryophyllaceae, although some morphologically distinct species were discernible, and most species were characterized by high host-specificity. In this study, anther smut specimens infecting Silene saxifragawere analysed using rDNA sequences (ITS and LSU) and morphology to resolve theirspecific status and to discuss their phylogenetic position within the lineage of caryophyllaceous anther smuts. The molecular phylogeny revealed that all specimens form a monophyletic lineage that is supported by the morphological trait of reticulate spores with tuberculate interspaces (observed in certain spores). This lineage cannot be attributed to any of the previously described species, and the anther smut on Silene saxifragais described and illustrated here as a new species, Microbotryum silenes-saxifragae.This species clusters in a clade that includes Microbotryumspecies, which infect both closely and distantly related host plants growing in diverse ecological habitats. It appears possible that host shifts combined with changes to ecological host niches drove the evolution of Microbotryumspecies within this clade.

The anther smut fungi in the ustilaginomycetous genus Antherospora (Floromycetaceae, Urocystidales)that infect monocots, are currently placed in nine species. Against the background of the generally observed high host specificity in smut fungi, the broad host range reported for some of the species suggests much higher diversity. Antherospora vaillantii s. latoincludes anther smuts on different Muscarispecies. In this study, specimens of anther smuts on Muscari armeniacum, M. botryoides, M. comosum, and M. tenuiflorumwere analysed by rDNA sequences and morphology to determine whether they represented one polyphagous or several host specific species. The molecular phylogeny revealed three distinct lineages that were correlated with host plants, yet had only slight morphological differences. These lineages are assigned to three cryptic species: Antherospora hortensissp. nov. on Muscari armeniacum, A. muscari-botryoidiscomb. nov. (syn. Ustilago muscari-botryoidis) on M. botryoides, and A. vaillantii s. str. on M. comosumand M. tenuiflorum. All species on Muscariform a monophyletic group within Antherospora, and the phylogenetic relations within this group coincide well with the subgeneric classification of the respective host species. This indicates a common ancestry of Muscarianther smuts and co-evolution as a driver of their diversification.

The morphology and phylogeny of Anthracoideaon Carex meadii(sect. Paniceae) collected in Illinois, Iowa, Wisconsin, USA, were studied by light microscopy, scanning electron microscopy and LSU rDNA sequence analyses. As a result A. caricis-meadiisp. nov. is described. The fungus differs morphologically from Anthracoidea laxaeand A. paniceae, which also occur on sedges from the section Paniceae. Molecular analyses support the placement of the latter species and Anthracoidea caricis-meadiiin different phylogenetic lineages. Because of morphological discrepancies in the literature, A. laxaeand A. paniceaealso are described and illustrated based on re-examination of respective holotype and isotype specimens.

The generic position of the enigmatic smut fungus Ustilago solidais evaluated applying molecular phylogenetic analyses using ITS and LSU rDNA sequences as well as light and scanning electron microscopical investigations of several collections of this species. Ustilago solidahas previously been included in five different genera (Ustilago, Urocystis, Sorosporium, Cintractia, and Tolyposporium), however, molecular analyses revealed that this smut does not belong to any of these genera and represents a distinct ustilaginalean lineage. The closest known phylogenetic relative of Ustilago solidais Heterotolyposporium lepidospermatis, the type species of the monotypic genus Heterotolyposporium. Both smuts differ considerably in both LSU sequences and in several morphological traits, such as the structure of sori and the characteristics of spore balls. Accordingly, the new genus Shivasiais described to accommodate Ustilago solida. This smut infects different Schoenusspecies (Cyperaceae)in Australia and New Zealand. The description of Shivasiaincreases the number of endemic smut genera in Australasia to ten. Compared to all other continents the number of endemic smut genera is exceptionally high, which may point at fast evolving characters and/or may be caused by the regional history, including the long-term geographic isolation of Australasia.

The morphology and phylogeny of anther smut specimens on Tractema vernacollected in the United Kingdom were investigated using light microscopy, scanning electron microscopy and partial rDNA sequence analyses. The anther smut of Tractema vernashows similarity to Antherospora eucomis, A. scillae, A. tourneuxii, A. urgineae, A. vaillantii, and A. vindobonensisbut differs in spore size range, spore wall thickness, host plant genera and considerable divergences of ITS and LSU sequences. Consequently, the smut is described here as a new species, Antherospora tractemae.The host plant was formerly included in the genus Scilla(S. verna), but recently moved to a distinct genus Tractema.Molecular phylogenetic analyses reveal that Antherospora tractemaeis sister to the lineage of Muscari-parasitizing Antherosporaand only distantly related to the Scilla-parasitizing Antherosporaspecies. Thus, the phylogenetic placement of the smut fungus supports the systematic placement of its host plant.

J. Piątek, M. Piątek, B.A. Zeeb andA. ElShahed. 2009. Chrysophyte stomatocysts in Africa: the first description of an assemblage in the recent sediments of a thermo-mineral spring in Egypt. Phycologia48: 13–23. DOI: 10.2216/08-50.1.An assemblage of chrysophycean stomatocysts from the recent sediments of a thermo-mineral spring in Ain Sukhna in Egypt was investigated using scanning electron microscopy. Seven stomatocysts are reported from the spring; four are described as new morphotypes, and three have previously been observed in various parts of the world. A new term, ‘ornamentation with bullate swellings,’ is introduced to describe a type of ornamentation not observed to date in any known stomatocysts. The present study documents for the first time an assemblage of chrysophyte stomatocysts from Africa in a unique ecosystem consisting of a thermal, highly mineralized spring.

Cintractia bulbostylidicolainfecting Bulbostylis capillaris(Cyperaceae) is described and illustrated as a new smut fungus from the U.S.A. It is characterized by the presence of inconspicuous sori produced usually in all flowers of an inflorescence, and by having medium-sized spores with finely, minutely reticulate-verruculose surface as seen by SEM. Cintractia bulbostylidicolais compared with species of Cintractiadescribed previously. The generic as well as familial placements of the new species are briefly discussed. Eleven accepted species of Cintractiaare enumerated and their most important diagnostic characteristics are given. A key to the smut fungi on Bulbostylisis provided.

The unambiguous application of fungal names is important to communicate scientific findings. Names are critical for (clinical) diagnostics, legal compliance, and regulatory controls, such as biosafety, food security, quarantine regulations, and industrial applications. Consequently, the stability of the taxonomic system and the traceability of nomenclatural changes is crucial for a broad range of users and taxonomists. The unambiguous application of names is assured by the preservation of nomenclatural history and the physical organisms representing a name. Fungi are extremely diverse in terms of ecology, lifestyle, and methods of study. Predominantly unicellular fungi known as yeasts are usually investigated as living cultures. Methods to characterize yeasts include physiological (growth) tests and experiments to induce a sexual morph; both methods require viable cultures. Thus, the preservation and availability of viable reference cultures are important, and cultures representing reference material are cited in species descriptions. Historical surveys revealed drawbacks and inconsistencies between past practices and modern requirements as stated in the International Code of Nomenclature for Algae, Fungi, and Plants(ICNafp). Improper typification of yeasts is a common problem, resulting in a large number invalid yeast species names. With this opinion letter, we address the problem that culturable microorganisms, notably some fungi and algae, require specific provisions under the ICNafp. We use yeasts as a prominent example of fungi known from cultures. But viable type material is important not only for yeasts, but also for other cultivable Fungithat are characterized by particular morphological structures (a specific type of spores), growth properties, and secondary metabolites. We summarize potential proposals which, in our opinion, will improve the stability of fungal names, in particular by protecting those names for which the reference material can be traced back to the original isolate.

AbstractMovement of six-legged robot is considered. The robot is built to conduct research on the control of different modes of walking with a particular focus on switching from one mode to another. The robot parameters are identified from real-time control experiments. A number of identical servo motors are responsible for the mobility of the hexapod. Therefore, in addition to the construction of hexapod and its control system and the ability to generate different gaits, it is important to create a simulation model of the hexapod including servo motors. The full state observer for the servo motor is an integral part of this model. Forward and backward kinematics of the robot legs is implemented. The six node Toda-Rayleigh lattice model is created and numerically simulated. The lattice is applied as the robot controller. Three different modes of robot gait are achieved. The algorithm used for the gait mode change is equipped with parameters that are experimentally chosen.