While surveying saprotrophic microfungi on Syagrus coronata (Arecaceae), an endemic palm in Brazil, an unusual fungus was identified occurring on the dead leaves of this plant. Morphologically, it showed the key traits of Yunnanomyces, including semi-macronematous conidiophores, integrated conidiogenous cells and globose to subglobose, ellipsoidal or irregularly shaped muriform conidia. Phylogenetic analyses using ITS, LSU, SSU, and rpb2 locus sequences confirmed its placement as a unique lineage among described species of Yunnanomyces, leading us to introduce it as Yunnanomyces syagri sp. nov.

In a continued effort to dismantle the Sticta fuliginosa morphodeme of western North America, we performed an extensive sampling throughout the mountainous regions of the southwestern states of the USA: Arizona, Colorado, and New Mexico. Recent studies have concluded the genus Sticta has extensive hidden biodiversity and is a large sub-cosmopolitan species-rich genus that encompasses 500+ taxa and counting. The prior treatment, incorporating all laminal isidiate species of Sticta into the Sticta fulignosa s.str. and Sticta sylvatica s.str. morphodemes, was incorrect. Our data does not support those previous treatments nor the broad application of European species concepts of isidiate Sticta in Western North America. Instead, our 4-locus phylogenetic analyses support a narrowing of that concept to a single species of Sticta that is neither S. fuliginosa s.str. nor S. sylvatica s.str. and is a distinct species with a specialized ecological niche. This unique proposed species is named and described here as Sticta puebloensis sp. nov.

We describe Diploschistes stereocaulorum as a new species of lichenized fungi growing on phyllocladia and stalks of Stereocaulon in the Pacific Northwest of North America. The larger ascospores of this species, the absence of a noticeable thallus, and the ITS barcode locus distinguish it from D. muscorum, which has been reported as growing on Stereocaulon, but has smaller ascospores and a distinct thallus. In phylogenetic reconstruction, the new species is sister to D. diacapsis, albeit without support.

This special issue of Plant and Fungal Systematics is dedicated to Prof. Tor Tnsberg on the occasion of his 75 th birthday.It presents 20 papers related to his scientific interests.Tor Tnsberg devoted his career to research in lichenology, including the taxonomy, chemistry, floristics, and phytogeography of lichens and lichenicolous fungi.Throughout his career, he has taken an interest in many groups of lichens, from Cladonia to his favourites, the sorediate crustose lichens, including the iconic genus Lepraria.Alone or together with his collaborators from several countries, he introduced more than one hundred species and genera new to science and has contributed substantially to the knowledge of lichens in Europe and North America.So far, the genus Toensbergia as well as nine species have been named in his honour.With this volume, the contributors wish to celebrate his impressive achievements in lichenology.We, the editors, also express our gratitude to all the authors, whose contributions made this celebration possible.

The lichenologist Tor Tønsberg (Fig. 1 ) was born in Oslo in 1948. It was not a bad start for a future botanist to grow up in Norway's capital city, for he lived in the outskirts of the city, close to the forested hills in its surroundings, "marka". Here he used to roam and was fascinated by the natural environment. It was therefore only natural that he, when entering the University of his native city in 1966, chose biology. After the basic courses he chose to specialize in botany. He discovered lichens during a course given by the bryologist Per Størmer (1907Størmer ( -1991)). This triggered him to take up closer studies on that theme for his cand.real thesis. Luckily, there was a lichenologist on the staff, Hildur Krog (1922Krog ( -2014)). She was part of the lichenological tradition (Jørgensen 2007) originating from Bernt Lynge , the great master of Arctic lichenology. This tradition had been renewed by his pupil Eilif Dahl (1916Dahl ( -1993) ) who introduced chemotaxonomy using the microcrystal tests invented by the Japanese Yasuhiko Asahina shortly before WWII. Tor was trained in this tradition, and later took up Thin Layer Chromatography (TLC), a method introduced by Krog (Jørgensen 2016). However, this thesis was a floristic/ phytogeographic study of a National Park, Børgefjell in Nordland, a region he knew from his childhood visits to his maternal grandparents who lived there. He earned a cand.real degree on this study in 1975. He retained this interest in floristics and phytogeography through his career, a most important result being the first Norwegian survey of threatened macrolichens (Tønsberg et al. 1996). He also participated in the publication of the first Norwegian flora of macrolichens (Krog et al. 1980) , and later in an illustrated lichen flora (Holien & Tønsberg 2006) with a much enlarged and revised edition in 2023. As a student, Tor became aware of the complexity of the species in the genus Cladonia and the lack of knowledge about them. In the following years he published a number of papers about them, recording several as new to the country, to Europe [e.g., C. alpina (Asahina) Yoshim., C. metacorallifera Asahina] and even one to science (Cladonia norvegica Tønsberg & Holien, Fig. 2 ).

Rocks are among the oldest terrestrial niches hosting a multiplicity of life forms, of which diversity has been only partially uncovered. Endolithic metacommunities comprise all major groups of microorganisms, such as chemo-organotrophic, chemo-lithotrophic and phototrophic, represented by bacteria, microalgae and microfungi. Their diversity is often difficult to describe and may remain underestimated. Furthermore, knowledge about the diversity of microorganisms colonizing rocks in peculiar niches is even poorer due to the difficulty to retrieve environmental specimens. Here, we report the phylogenetic and phenotypic characterization of a few endolithic fungi and algae isolated from rock fragments collected at high elevation, i.e., on the top of two mountains over 6000 m altitude, Muztagh Ata (China) and Cerro Mercendario (Argentina). The identity of the strains was confirmed by sequencing the nuclear ITS and LSU, the plastidial rbcL loci and by morphological analysis. Three fungal strains belonging to the class Dothideomycetes and one algal strain belonging to the genus Trebouxia were isolated from Muztagh Ata, while six fungal strains belonging to the order Chaetothyriales and four algal strains belonging to the genus Myrmecia were isolated from Cerro Mercedario. The detected species diversity is discussed in an evolutionary and ecological context.

A survey of the diversity and community composition of culturable endophytic fungi associated with photosynthetic stems of the gnetophyte Ephedra trifurca (Ephedraceae) in southeastern Arizona, USA, yielded numerous isolates that are consistent morphologically with members of the genus Preussia (Sporormiaceae, Pleosporales, Dothideomycetes, Ascomycota). Preussia (including species until recently classified within Sporormiella) include dung-, soil-, and plant-inhabiting strains with considerable diversity worldwide. We used morphological evidence and phylogenetic analyses (nuclear ribosomal internal transcribed spacers and 5.8s gene, the adjacent D1-D2 region of the nuclear ribosomal large subunit, and for a subset of strains, the translation elongation factor 1-alpha, EF1-a) to identify distinctive members of the Preussia intermedia clade occurring as endophytes in E. trifurca. These include P. arizonica sp. nov., which also occurs as an endophyte in other plants of the region, and P. elegans sp. nov., which has been found only in E. trifurca to date. We also propose Preussia mariae sp. nov., allied phylogenetically with Preussia lignicola but distinguishable on the basis of morphology and EF1-a data. Our analyses illustrate the potential for several currently recognized species of Preussia to represent species complexes that should be resolved by analyses of additional loci and by further sampling of endophytes, which may provide an ecological connection among strains occurring within living plant tissues and as coprophilous or soil-inhabiting fungi. More broadly, our work expands the known geographic scope, host use, and diversity of Preussia, especially in arid lands. In conjunction with previous work, our study also provides the basis for hypotheses regarding secondary metabolites of the newly described species.

Two species of Tricholoma, T. bonii and T. triste, are reported as new records for Pakistan. Phylogenetic analysis based on the nuclear ribosomal internal transcribed spacer (nrITS) region clustered the Pakistani collections with T. bonii and T. triste sequences from previous worldwide collections. Detailed descriptions of macro- and microcharacters, habitat, general distribution, and diagnostic features are presented.

Quercus ningangensis is an economically and ecologically important tree species belonging to the family Fagaceae. In this study, the complete chloroplast (cp) genome of Q. ningangensis was sequenced and assembled, and 18 published cp genomes of Quercus were retrieved for genomic analyses (including sequence divergence, repeat elements, and structure) and phylogenetic inference. With this study, we found that complete cp genomes in Quercus are conserved, and we discovered a codon composition bias, which may be related to genomic content and genetic characteristics. In addition, we detected considerable structural variations in the expansion and contraction of inverted repeat regions. Six regions with relatively high variable (matK-rps16, psbC, ycf3 intron, rbcL, petA-psbJ, and ycf1) were detected by conducting a sliding window analysis, which has a high potential for developing effective genetic markers. Phylogenetic analysis based on Bayesian inference and maximum likelihood methods resulted in a robust phylogenetic tree of Quercus with high resolution for nearly all identified nodes. The phylogenetic relationships showed that the phylogenetic position of Q. ningangensis was located between Q. sichourensis and Q. acuta. The results of this study contribute to future research into the phylogenetic evolution of Quercus section Cyclobalanopsis (Fagaceae).

Phylogenetic relationships between Usnea nipparensis and U. sinensis, caperatic acid containing Usnea species, were examined based on ITS rDNA, and the phylogenetic position of U. nipparensis was inferred based on multi-locus gene analysis using ITS rDNA, nuLSU, and MCM7. Although U. nipparensis and U. sinensis have a sorediate and an esorediate shrubby thallus, respectively, and in general look quite different, other detailed morphological and chemical features are similar. Analysis of the ITS rDNA sequences suggests their close relationship, but also confirms the independence of both species, and that they most likely form a ‘species pair’ based on morphological, chemical and molecular phylogenetic data. Phylogenetic trees based on both multi-locus gene and ITS rDNA alone strongly support that U. nipparensis and U. angulata belong to the same clade.