Browsing by Subject "Ascomycota"

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  • Rikkinen, Jouko; Meinke, Kristin; Grabenhorst, Heinrich; Gröhn, Carsten; Kobbert, Max; Wunderlich, Jörg; Schmidt, Alexander (2018)
    Calicioid lichens and fungi are a polyphyletic grouping of tiny ascomycetes that accumulate a persistent spore mass (mazaedium) on top of their usually well-stalked ascomata ('mazaediate fungi'). In addition to extant forms, six fossils of the group were previously known from European Paleogene amber. Here we report nine new fossils and analyze the preserved features of all fossils to assess their applicability for dating molecular phylogenies. Many fossils are extremely well preserved, allowing detailed comparisons with modern taxa. SEM investigation reveals that even fine details of ascospore wall ultrastructure correspond to those seen in extant specimens. All fossils can confidently be assigned to modern genera: three to Calicium (Caliciaceae, Lecanoromycetes), five to Chaenotheca (Coniocybaceae, Coniocybomycetes), six to Chaenothecopsis (Mycocaliciaceae, Eurotiales), and one to Phaeocalicium (Mycocaliciaceae, Eurotiales). Several Calicium and Chaenotheca fossils are assignable to specific lineages within their genera, while the Chaenothecopsis fossils demonstrate the extent of intraspecific variation within one such lineage. Some features in the morphology of Chaenotheca succina nov. sp. seem to be ancestral as they have not been reported from modern species of the genus. (C) 2018 Elsevier Masson SAS. All rights reserved.
  • von Cräutlein, Maria; Korpelainen, Helena; Helander, Marjo; Saikkonen, Kari; Ohberg, Annika (2014)
  • Kettunen, Elina Johanna; Schmidt, Alexander; Diederich, Paul; Grabenhorst, Heinrich; Rikkinen, Jouko (2018)
    A diversity of filamentous microfungi was discovered from thallus surfaces of epiphytic lichens preserved in Bitterfeld and Baltic amber. We report seven distinct morphologies of dematiaceous hyphomycetes, some of which closely resemble species of the extant genera Sporidesmium, Taeniolella s. lat. and Taeniolina. Both the placement of the fungi on their substrates and the exquisite preservation of delicate structures indicate that the fungi were fully developed before they were engulfed by fresh resin. The lichens probably grew on the trunks of resin producing trees and became embedded in resin flows together with their fungal associates. The findings demonstrate that a wide range of presumably specialised fungi have lived on living and decomposing lichen thalli at least since the Paleogene. The findings add an interesting new component to the as yet poorly known mycota of the ancient European amber forests.
  • Beimforde, Christina; Feldberg, Kathrin; Nylinder, Stephan; Rikkinen, Jouko; Tuovila, Hanna; Doerfelt, Heinrich; Gube, Matthias; Jackson, Daniel J.; Reitner, Joachim; Seyfullah, Leyla J.; Schmidt, Alexander R. (2014)
  • Kaasalainen, Ulla Susanna; Rikkinen, Jouko Kalevi; Schmidt, Alexander (2020)
    Fruticose lichens of the genus Usnea Dill. ex Adans. (Parmeliaceae), generally known as beard lichens, are among the most iconic epiphytic lichens in modern forest ecosystems. Many of the c. 350 currently recognized species are widely distributed and have been used as bioindicators in air pollution studies. Here we demonstrate that usneoid lichens were present in the Palaeogene amber forests of Europe. Based on general morphology and annular cortical fragmentation, one fossil from Baltic amber can be assigned to the extant genus Usnea. The unique type of cortical cracking indirectly demonstrates the presence of a central cord that keeps the branch intact even when its cortex is split into vertebrae-like segments. This evolutionary innovation has remained unchanged since the Palaeogene, contributing to the considerable ecological flexibility that allows Usnea species to flourish in a wide variety of ecosystems and climate regimes. The fossil sets the minimum age for Usnea to 34 million years (late Eocene). While the other similar fossils from Baltic and Bitterfeld ambers cannot be definitely assigned to the same genus, they underline the diversity of pendant lichens in Palaeogene amber forests.
  • Tedersoo, Leho; Sanchez-Ramirez, Santiago; Koljalg, Urmas; Bahram, Mohammad; Doring, Markus; Schigel, Dmitry; May, Tom; Ryberg, Martin; Abarenkov, Kessy (2018)
    High-throughput sequencing studies generate vast amounts of taxonomic data. Evolutionary ecological hypotheses of the recovered taxa and Species Hypotheses are difficult to test due to problems with alignments and the lack of a phylogenetic backbone. We propose an updated phylum-and class-level fungal classification accounting for monophyly and divergence time so that the main taxonomic ranks are more informative. Based on phylogenies and divergence time estimates, we adopt phylum rank to Aphelidiomycota, Basidiobolomycota, Calcarisporiellomycota, Glomeromycota, Entomophthoromycota, Entorrhizomycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota and Olpidiomycota. We accept nine subkingdoms to accommodate these 18 phyla. We consider the kingdom Nucleariae (phyla Nuclearida and Fonticulida) as a sister group to the Fungi. We also introduce a perl script and a newick-formatted classification backbone for assigning Species Hypotheses into a hierarchical taxonomic framework, using this or any other classification system. We provide an example of testing evolutionary ecological hypotheses based on a global soil fungal data set.
  • Guo, Qingxue; Yan, Lijuan; Korpelainen, Helena; Niinemets, Ülo; Li, Chunyang (2019)
    The impact of conspecific and heterospecific neighboring plants on soil bacterial and fungal communities has never been explored in a forest ecosystem. In the present study, we first investigated soil microbial communities in three plantations: Larix kaempferi monoculture, L. olgensis monoculture and their mixture. Then, a two-year growth experiment was conducted to investigate the effects of intra- and inter-specific interactions of L. kaempferi and L. olgensis on rhizosphere microbial communities at two different nitrogen levels. The results demonstrated clear differences in the beta-diversity and composition of bacteria and fungi among the three plantations, which implied the presence of different effects of plant-plant interactions on soil microbial communities. The results of the pot experiment showed that L. kaempferi suffered from greater neighbor effects from its conspecific neighbor regardless of N fertilization, although the effect declined when L. kaempferi was grown with L. olgensis under N fertilization. Changes in intra- and inter-specific plant interactions significantly impacted the chemical and biological properties of soil under N fertilization, with lower concentrations of NH4+, and lower soil microbial biomass (C-Mic) and soil carbon nitrogen biomass (N-Mic) under intra-specific plant interactions of L. kaempferi (KK) compared to inter-specific interactions of L. kaempferi and L. olgensis (KO). N fertilization increased bacterial and fungal alpha diversities in the rhizosphere soil of KO. For the beta diversity, the PERMANOVA results demonstrated that there was a significant impact of intra- and inter-specific plant interactions on soil microbial communities, with KK significantly differing from intra-specific plant interactions of L. olgensis (OO) and KO. The two plant species and N fertilization showed specific effects on the soil microbial composition, particularly on the fungal community. Both L. olgensis and N fertilization increased the abundance of Ascomycota but reduced that of Basidiomycota, and even shifted the dominance from Basidiomycota to Ascomycota under KO combined with N fertilization.
  • Suija, Ave; Kaasalainen, Ulla Susanna; Kirika, Paul; Rikkinen, Jouko Kalevi (2018)
    During lichenological explorations of tropical montane forests in Kenya, a remarkable new lichenicolous fungus was repeatedly found growing on thalli of the epiphytic tripartite cyanolichen Crocodia cf. clathrata. Molecular phylogenetic analyses placed the fungus within Gomphillaceae (Ostropales, Lecanoromycetes), a family mainly of lichen-symbiotic species in the tropics. The anatomical features (unitunicate, non-amyloid asci and simple, septate paraphyses) as well as the hemiangiocarpic ascoma development confirm its taxonomic affinity. DNA sequence data showed the closest relationship was with Gyalidea fritzei, followed by Corticifraga peltigerae. A monotypic genus, Taitaia, is introduced to incorporate a single species, T. aurea. The new fungus is characterized by aggregated ascomata with yellow margins and salmon red discs developing from a single base.
  • Pykälä, Juha; Kantelinen, Annina; Myllys, Leena (2020)
    Species of Verrucaria, characterised by large spores (at least some spores exceeding 25 mu m in length), perithecia leaving pits in the rock and a pale thin thallus, form a taxonomically-difficult and poorlyknown group. In this study, such species occurring in Finland are revised, based on ITS sequences and morphology. Maximum likelihood analysis of ITS sequence data was used to examine if the species belong to the Thelidium group, as suggested by BLAST search. Twelve species are accepted in Finland: Verrucaria bifurcata sp. nov., V. cavernarum sp. nov., V. devergens, V. difficilis sp. nov., V. foveolata, V. fuscozonata sp. nov., V. karelica, V. kuusamoensis sp. nov., V. subdevergens sp. nov., V. subjunctiva, V. subtilis and V. vacillans sp. nov. Verrucaria foveolata is nested in V. subjunctiva in the phylogeny, but due to morphological and ecogeographical differences, the two taxa are treated as separate species pending further studies. Based on the analysis, the study species belong to the Thelidium group. The studied species show a rather high infraspecific morphological, but a low genetic variation. Furthermore, they show considerable overlap in their morphology and many specimens cannot be reliably identified, based on morphology only. All species arc restricted to calcareous rocks. Verrucaria alpigena, V. cinereoruh and V. bochstetteri are excluded from the lichen flora of Finland. Verrucaria gmssa is considered a species with unresolved identity. Verrucaria foveolata and V. subtilis are rather common on calcareous rocks of Finland while V. devergens and V. kuusamoensis are restricted to northern Finland. Verrucaria subjunctiva occurs mainly in northern Finland. Verrucaria bifurcata has been found only from southern Finland. Verrucaria difficilis has few localities both in SW and NE Finland. Verrucaria vaeillans is restricted to calcareous roc ks (dolomite) on the mountains of the NW corner of Finland. Verrucaria Jiacozonata, V. karelica and V. sulideveTens occur only in the Oulanka area in NE Finland. A lectotype is designated for V. subjunctiva. The morphology of the Finnish species was compared with 51 European species of Verrucaria presumably belonging to the Theliolium group.
  • Oranen, Heidi (Helsingfors universitet, 2013)
    Filamentous fungi vectored by Trypodendron lineatum were identified. The mycota of flying beetles was distinguished from that of hatching ones. The purpose was also to study to what extent T. lineatum is associated with specific fungal partners and opportunistic fungi. The hypotheses stated that: the proportions of beetles carrying epi- and endomycetes (positioned to outer surface and inner parts of insect, respectively) differ (1); proportions of beetles that get attached to fungal propagules vary between collection methods (pheromone traps and stumps) (2); the frequencies of fungal iso-lates differ between positions (3); the frequencies of isolates are unequal between collection meth-ods (4). The beetles were collected from two clear felled spruce dominated sites in Southern Finland with pheromone traps in spring and sawing pieces of stumps in summer. The experimental design of this study is unique in studying the effect of trapping time and method on the resulting assemblage of fungi. Identification of fungi rests on morphological characteristics and DNA-based methods. The sequences were compared against BLAST. The hypotheses were tested statistically using odds ratio (logistic regression) for proportions and ratio of averages (Poisson regression) for frequencies. Species richness and diversity for positions, trap types, sites and treatment methods were analyzed using Shannon-Wiener Diversity Index/Shannon Entropy Calculator and EstimateS. The proportion of beetles carrying epimycetes was greater than that of endomycetes (1). The proportions of vector beetles were not significantly affected by trap type (2). The frequencies of fungal isolates were higher among the epimycota (3). Trap types had no impact on the frequencies of isolated fungi (4). Species richness and diversity analyses supported the outcome of the tested hypotheses. Additionally, they indicated similarity between the mycota of the sites, whereas conclu-sions concerning the treatment methods could not be made. Seven genera (Penicillium sp., Cadophora sp., Cladosporium sp., Rhizosphaera sp., Sydowia sp., Absidia sp. and Mucor sp.) were discovered associated to the striped ambrosia beetle as new. Swarming beetles and those leaving stumps were observed to carry different assemblages of fungi. Origin of the Zygomycota was only traced to the beetles hatching from stumps in midsummer. 61.84 % of the isolates belonged to the Ascomycota, 10.53 % to the Zygomycota and 27.63 % remained unidentified. Best concentrated genera were Hypocrea, Ophiostoma and Sydowia.