Seente perekonna Cerinomyces ja lähedaste taksonite süstemaatika ning fülogenees

Väitekirja elektrooniline versioon ei sisalda publikatsioonePäristuumsete hulgas on seened üks suuremaid ja liigirikkamaid eluslooduse riike. Kandseened on omakorda üks seente liigirikkam hõimkond, mille hulka kuuluvad nii surnud orgaanilise aine lagundajad kui ka taimejuurtega sümbioosis elavad organismid. Vaatamata kandseente olulisele ökoloogilisele rollile, on nende taksonoomia ja ökoloogia siiani ebapiisavalt uuritud. Käesolev doktoritöö hõlmab kandseente klassi pisarseened (Dacrymycetes) taksonoomia ja evolutsiooni uuringuid. Pisarseened kasvavad kõdupuidul ja neil areneb kahte tüüpi viljakehi: kollased sültjad või tuhmi värvi koorikjad viljakehad. Enne seda uurimistööd arvati koorikjate viljakehadega pisarseente liigid sugukonda Cerinomycetaceae ja selle ainsasse perekonda Cerinomyces. Selline lihtsustatud süstemaatika on viinud olukorrani, kus perekonda Cerinomyces kuulub palju liike, mis pole omavahel lähisuguluses. Käesoleva doktoritöö eesmärgiks oligi uurida perekonna Cerinomyces ja sellele morfoloogiliselt sarnaseid liike. Selleks kasutati nii DNA järjestusi kui ka morfoloogilisi ning anatoomilisi tunnuseid, mille põhjal viidi läbi fülogeneetilised analüüsid. Selle töö põhjal esitati teadusele uus monofüleetilise perekonna Cerinomyces kontseptsioon. Cerinomyces perekonda on nüüd arvatud nii sültjate kui ka liibuvate viljakehadega liigid. Esitati perekonnale Cerinomyces unikaalsete tunnuste kombinatsioon: seeneniitidel lihtsa ehitusega pandlad, kõver-silinderjad õhukesekestalised eosed ning vähene karotenoidsete pigmentide sisaldus seeneniitides ja eostes. Lisaks käsitleb doktoritöö perekonna Cerinomyces liikidele morfoloogiliselt sarnaseid taksoneid. Põhjalikult uuriti nn. dendrohüfiide, mis osutus perekonna Cerinomyces ja teisi lähedasi liike hästi eristavaks tunnuseks. Hüfiidid on ka doktoritöös kirjeldatud uue perekonna Dendrodacrys iseloomulikuks tunnuseks. Lisaks uuele perekonnale kirjeldati doktoritöös 27 teadusele uut liiki.Fungi represent one of the largest and diverse kingdoms of eukaryotes. Basidiomycota is the second most species-rich group within Fungi. Despite the ecological importance of Basidiomycota, i.e., its leading role in decomposition of wood in terrestrial ecosystems, its diversity and taxonomy are insufficiently known. Fulfilling the knowledge gap, the thesis presents taxonomic studies in dacrymycetes (Basidiomycota). Dacrymycetes occur only on dead wood and produce either of the two types of fruitbodies: gelatinous voluminous yellow or dry flat bleak-coloured. The latter type, also called corticioid fruitbodies, is the primary focus of the thesis. Traditionally, such corticioid fruitbodies in dacrymycetes were strictly associated with the family Cerinomycetaceae and its only genus Cerinomyces. This emphasis on a single character led to inclusion of dissimilar species into Cerinomyces, and over the time the genus became overly broad and polyphyletic. Thus, aim of the present thesis was to revise Cerinomyces and related taxa on a basis of DNA sequence-based phylogenetic analyses and morphological studies. As a result, Cerinomyces was reshaped to a more natural scope and became monophyletic. Priority for the corticioid morphology was abandoned, and gelatinous members were introduced to the genus. Instead of fruitbody type, the genus is now united by a set of microscopic characters: simple clamps, thin-walled aseptate basidiospores, and low amount of carotenoid pigments. Moreover, investigating taxa morphologically similar to Cerinomyces, the rest of dacrymycetes was partially revised. Special attention was paid to notable morphological structures called “dendrohyphidia” that are common in Cerinomyces, but were also found in other dacrymycetes. To accommodate such taxa in the Dacrymycetaceae family, a new genus Dendrodacrys was raised. In total, the thesis proposes 42 nomenclatural novelties to science, including one new genus, 27 new species, and 14 new combinations.https://www.ester.ee/record=b553990

Barless flocculent galaxies: a dynamic puzzle

We draw attention to the bright galaxies that do not show a bar in their structure but have a flocculent spiral structure. Using the THINGS' and HERACLES' kinematic data for four barless galaxies (NGC~2841, NGC~3512, NGC~5055, NGC~7331) we built their mass models including dark halos. We concluded that the fraction of the dark matter does not exceed 50\% within the optical radii of the galaxies. This is too little to explain the lack of a bar in these galaxies. In an attempt to understand the featureless structure of these galaxies we constructed several $N$-body models with an initially reduced content of dark matter. We concluded that, in addition to the low mass of the dark halo, the decisive factor that leads to a barless disc is the start from an initially unstable state. An isolated dynamically cold disc (with the Toomre parameter $Q < 0.5$) settled into rotational equilibrium passes trough the short stage of violent instability with fragmentation and formation of stellar clumps. After that, it evolves passively and ends up with a featureless structure. We assume that the barless flocculent galaxies studied in the present work may be descendants of galaxies at high redshifts with rotation curves which are consistent with the high mass fraction of baryons relative to the total dark matter halo.Comment: 18 page

Additions to Dendrodacrys and outline of taxa with branched hyphidia in Dacrymycetes (Basidiomycota)

The genus Dendrodacrys is a monophyletic group that belongs to Dacrymycetes (Agaricomycotina, Basidiomycota) and accommodates species distinguished by strongly branched hyphidia in combination with 3-septate basidiospores. While the original circumscription mainly treated European taxa, here we shift the focus to tropical and sub-tropical material and uncover wider variation in morphology within Dendrodacrys. Still united by hyphidia shape and basidiospore septation, the genus is expanded with 10 taxa having pustulate, cerebriform, or stipitate basidiocarps of yellow to dark brown colours, cylindrical to ovoid basidiospores, and hyphal septa with or without clamps. Monophyly of the amended Dendrodacrys is confirmed with a phylogeny based on six markers (SSU, ITS, LSU, TEF1-α, RPB1, and RPB2). As a result, we describe two new species (De. laetum and De. rigoratum), transfer three existing species to Dendrodacrys (De. brasiliense, De. dendrocalami, and De. pezizoideum), and raise one variety to the species level (De. kennedyae ≡ Dacrymyces enatus var. macrosporus). In addition, we provide descriptions for the earlier combined De. paraphysatum and four new informal taxa. Lastly, we present illustrations, a character table, and an identification key that addresses all known dacrymycetes with branched hyphidia.Peer reviewe

On Craterocolla and Ditangium (Sebacinales, Basidiomycota)

In the present paper, we select a neotype for Tremella cerasi and prove that it is conspecific with Ditangium insigne (the genus type of Ditangium). We argue that Ditangium should be restored as a correct genus for T. cerasi, while the currently used generic name Craterocolla is to be treated as its younger synonym. Morphological, ecological and genetic variability of Ditangium cerasi is discussed, and two other Ditangium species are described—D. altaicum, sp. nov. and D. incarnatum, comb. nov. In addition, Exidia fulva is combined in Globulisebacina.Peer reviewe

Fungi from Soomaa National Park : rarities and species new for Estonia

Peer reviewe

Do plant-based biogeographical regions shape aphyllophoroid fungal communities in Europe?

Aim: Aphyllophoroid fungi are associated with plants, either using plants as a resource (as parasites or decomposers) or as symbionts (as mycorrhizal partners). In spite of their strong association with plants, it is unknown how much plant distributions determine their biogeographical patterns compared with environmental factors such as climate and human land use. In this study, our aims are to (1) describe the spatial diversity patterns of aphyllophoroid fungi in Europe and (2) identify the factors shaping these patterns. Location: Europe, as well as the adjacent Subarctic to Arctic islands (Greenland, Faroe Islands, Iceland, Svalbard), Palestine and the south-east coast of the Caspian Sea. Methods: We compiled a dataset consisting of 14,030 fruitbody occurrences of 1,491 aphyllophoroid fungal species from 39 geographical areas (17 countries) belonging to eight biogeographical regions. We assessed the differences in fungal species richness and overall diversity and its nestedness and turnover components across biogeographical regions of Europe, as well as between southern and northern Europe (based on geographical latitude of 50 degrees as threshold). We used cluster and ordination analyses to classify the European aphyllophoroid communities biogeographically and evaluated the importance of climate, host-tree species, topography and human land-use intensity in explaining biogeographical variation. Results: The importance of biogeographical regions in determining European aphyllophoroid fungal communities varies for different diversity components. Species richness and nestedness are best explained by plant-based biogeographical regions, whereas overall beta diversity and species turnover are driven mostly by variation in climate, and nestedness mostly by tree species occupancy. Beta-diversity patterns of aphyllophoroid fungi do not differ between southern and northern Europe. Main conclusions: At the continental scale, aphyllophoroid fungi are less shaped by historical legacies than vascular plant and animal communities, and trends of overall beta diversity in southern and northern Europe are similar to patterns found for bryophytes.Peer reviewe

Оцінка ризиків використання банківських груп у тіньових операціях

Наведено результати аналізу показників, які характеризують ризики використання банківських груп у тіньових схемах. За результатами кластерного аналізу сформовано чотири кластери банківських груп. Це дозволить у подальшому більш системно та обґрунтовано проводити компаративний аналіз показників банківських груп на предмет виявлення спільних якісних і кількісних характеристик, що описуватимуть їхні ризики участі в нелегальних операціях. На другому етапі методом головних компонент виявлено показники, які найбільш істотно впливають на потенційні ризики участі банківських груп у тіньових операціях. На третьому етапі сформовано статистично значущу регресійну модель, що підтверджує вплив кількості фінансових установ у складі банківської групи і загальної кількості учасників банківської групи на потенційний ризик використання банківських груп у тіньових операціях. Отримані результати в подальшому можуть також використовуватись для формування інтегральної оцінки потенційного ризику використання банківських груп у тіньових операціях, а також для поліпшення банківського наглядуПриведены результаты анализа показателей, характеризующих риски использования банковских групп в теневых схемах. По результатам кластерного анализа сформированы четыре кластера банковских групп. Это позволит в дальнейшем более системно и обоснованно проводить компаративный анализ показателей банковских групп на предмет выявления общих качественных и количественных характеристик, описывать их риски участия в нелегальных операциях. На втором этапе методом главных компонент обнаружено показатели, которые наиболее существенно влияют на потенциальные риски участия банковских групп в теневых операциях. На третьем этапе сформирован статистически значимую регрессионную модель, что подтверждает влияние количества финансовых учреждений в составе банковской группы и общей количества участников банковской группы на потенциальный риск использования банковских групп в теневых операциях. Полученные результаты в дальнейшем могут также использоваться для формирования интегральной оценки потенциального риска использования банковских групп в теневых операциях, а также для улучшения банковского надзораIn a market economy, financial intermediaries become direct or indirect participants in most shadow schemes. Taking to account the bank-centric nature of the Ukrainian financial sector, banks and banking groups are a critical element of shadow operations. The article presents the analysis of indicators that characterize the risks of using banking groups in shadow schemes. According to the results of cluster analysis, four clusters of banking groups were formed. This will allow a more systematic and reasonable analysis of the performance of banking groups to identify common qualitative and quantitative characteristics that will describe their risks of participation in illegal transactions. In the second stage, the principal components method revealed the indicators that most significantly affect the potential risks of participation of banking groups in shadow operations. Such indicators include the number of financial institutions in the group, the residency of the group controllers, and the total number of group members. At the third stage, a statistically significant regression model was formed, which confirms the influence of the number of financial institutions in the banking group and the total number of banking group members on the potential risk of using banking groups in shadow operations. The obtained results can be further used to form an integrated assessment of the potential risk of using banking groups in shadow operations and improve banking supervision