Photobiont switching causes changes in the reproduction strategy and phenotypic dimorphism in the Arthoniomycetes

Phylogenetic analyses using mtSSU and nuITS sequences of Buellia violaceofusca (previously placed in Lecanoromycetes), a sterile, sorediate lichen having a trebouxioid photobiont, surprisingly prove that the species is conspecific with Lecanographa amylacea (Arthoniomycetes), a fertile, esorediate species with a trentepohlioid photobiont. These results suggest that L. amylacea and B. violaceofusca are photomorphs of the same mycobiont species, which, depending on the photobiont type, changes the morphology and the reproduction strategy. This is the first example of a lichenized fungus that can select between Trebouxia (Trebouxiophyceae) and trentepohlioid (Ulvophyceae) photobionts. Trebouxia photobionts from the sorediate morphotype belong to at least three different phylogenetic clades, and the results suggest that Lecanographa amylacea can capture the photobiont of other lichens such as Chrysothrix candelaris to form the sorediate morphotype. Phylogenetic analyses based on rbcL DNA data suggest that the trentepohlioid photobiont of L. amylacea is closely related to Trentepohlia isolated from fruticose lichens. The flexibility in the photobiont choice enables L. amylacea to use a larger range of tree hosts. This strategy helps the lichen to withstand changes of environmental conditions, to widen its distribution range and to increase its population size, which is particularly important for the survival of this rare species

Phylogeny of the genus Loxospora s.l. (Sarrameanales, Lecanoromycetes, Ascomycota), with Chicitaea gen. nov. and five new combinations in Chicitaea and Loxospora

Loxospora is a genus of crustose lichens containing 13 accepted species that can be separated into two groups, based on differences in secondary chemistry that correlate with differences in characters of the sexual reproductive structures (asci and ascospores). Molecular phylogenetic analyses recovered these groups as monophyletic and support their recognition as distinct genera that differ in phenotypic characters. Species containing 2’-O-methylperlatolic acid are transferred to the new genus, Chicitaea Guzow-Krzem., Kukwa & Lendemer and four new combinations are proposed: C. assateaguensis (Lendemer) Guzow-Krzem., Kukwa & Lendemer, C. confusa (Lendemer) Guzow-Krzem., Kukwa & Lendemer, C. cristinae (Guzow-Krzem., Łubek, Kubiak & Kukwa) Guzow-Krzem., Kukwa & Lendemer and C. lecanoriformis (Lumbsch, A.W. Archer & Elix) Guzow-Krzem., Kukwa & Lendemer. The remaining species produce thamnolic acid and represent Loxospora s.str. Haplotype analyses recovered sequences of L. elatina in two distinct groups, one corresponding to L. elatina s.str. and one to Pertusaria chloropolia, the latter being resurrected from synonymy of L. elatina and, thus, requiring the combination, L. chloropolia (Erichsen) Ptach-Styn, Guzow-Krzem., Tønsberg & Kukwa. Sequences of L. ochrophaea were found to be intermixed within the otherwise monophyletic L. elatina s.str. These two taxa, which differ in contrasting reproductive mode and overall geographic distributions, are maintained as distinct, pending further studies with additional molecular loci. Lectotypes are selected for Lecanora elatina, Pertusaria chloropolia and P. chloropolia f. cana. The latter is a synonym of Loxospora chloropolia. New primers for the amplification of mtSSU are also presented

Pseudolepraria, a new leprose genus revealed in Ramalinaceae (Ascomycota, Lecanoromycetes, Lecanorales) to accommodate Lepraria stephaniana

The new genus Pseudolepraria Kukwa, Jabłońska, Kosecka & Guzow-Krzemińska is introduced to accommodate Lepraria stephaniana Elix, Flakus & Kukwa. Phylogenetic analyses of nucITS, nucLSU, mtSSU and RPB2 markers recovered the new genus in the family Ramalinaceae with strong support. The genus is characterised by its thick, unstratified thallus composed entirely of soredia-like granules, the presence of 4-O-methylleprolomin, salazinic acid, zeorin and unknown terpenoid, and its phylogenetic position. The new combination, P. stephaniana (Elix, Flakus & Kukwa) Kukwa, Jabłońska, Kosecka & Guzow-Krzemińska, is proposed

Understanding the evolution of phenotypical characters in the Micarea prasina group (Pilocarpaceae) and descriptions of six new species within the group

peer reviewe

Research methods in modern taxonomy of lichens

Porosty to symbiotyczne układy tworzone przez co najmniej dwa genetycznie odmienne organizmy: grzyba, zielenicę lub sinicę. Systematyka porostów stanowi integralną część systemu klasyfikacyjnego grzybów i nazwa mikobionta jest nazwą gatunkową porostu, który tworzy, natomiast organizm autotroficzny klasyfikowany jest niezależnie. W pracy omówione są metody badawcze współcześnie stosowane w taksonomii porostów. Dane morfologiczno-anatomiczne oraz cechy chemiczne od wielu lat są wykorzystywane do identyfikacji porostów. Za pomocą prostych testów plamkowych, mikrokrystalizacji oraz metod chromatograficznych (TLC, HP TLC i HPLC) identyfikowane są wtórne metabolity obecne w plechach porostów. Jednak współczesne badania molekularne sugerują konieczność weryfikacji znaczenia taksonomicznego poszczególnych cech, zarówno anatomicznych, morfologicznych jak i chemicznych. W oparciu o zmienność na poziomie DNA identyfikowane są gatunki kryptyczne, których odrębność potwierdzają w dalszych analizach drobne cechy morfologiczno-anatomiczne. Przez wiele lat identyfikacja f otobiontów możliwa była jedynie po izolacji szczepu z plechy i jego hodowli w stanie aposymbiotycznym. Jednakże wykorzystanie specyficznych starterów pozwalających na selektywną amplifikację DNA partnerów glonowych pozwala zidentyfikować gatunki fotobiontów bez czasochłonnych hodowli in vitro. Markery DNA wykorzystywane jako barkody stanowią nowe narzędzie do oznaczania gatunków. Ponadto, rozwój technologii informacyjnych stworzył nowe możliwości rozpowszechniania i wymiany danych taksonomicznych. Tworzone są bazy danych dostępne on-line zawierające informacje na temat różnorodności porostów w poszczególnych obszarach geograficznych, bazy znanych i nowo opisanych taksonów, wyszukiwarki barkodów DNA, bazy literatury taksonomicznej i interaktywnych kluczy do oznaczania. Opracowywane są również elektroniczne klucze do oznaczania porostów, które powinny ułatwić identyfikację okazów.Lichens are symbiotic associations, composed of a fungus and green alga, and/or cyanobacterium, but lichen systematics deals with their fungal partners and photobionts are classified separately. In the paper research methods used in lichen taxonomy are briefly reviewed. Besides morphological and anatomical studies, chemotaxonomy became a very important tool for identification of lichens. Using simple spot tests, microcrystal tests and chromatography (TLC, HPTLC and HPLC) secondary metabolites are identified. With the introduction of molecular approaches, traditionally used characters, such as anatomy, morphology and chemistry need to be re-evaluated. Cryptic species are identified based on molecular variation and hidden biodiversity is being discovered. For many years identification of lichen photobionts was possible only after isolation and aposymbiotic growth of an algal strain. However, using specific primers appropriate molecular markers are amplified and the algal partners are identified without time-consuming in vitro culture. DNA markers used as barcodes provide a new tool for determination of species. Moreover, the development of information technology created new opportunities for dissemination and exchange of taxonomical data. On-line databases containing information on lichens from particular areas, newly described taxa, DNA barcodes, taxonomical literature etc. and interactive determination keys are being developed

Infraspecific variation of some brown Parmeliae (in Poland) – a comparison of ITS rDNA and non-molecular characters

Infraspecific variation of the ITS rDNA region of some brown Parmeliae occurring in Poland is studied and compared with non-molecular characters. Haplotype networks are used to illustrate the variability within the species. Both newly-produced sequences from Central Europe and from all over the world, downloaded from the GenBank, are used. The number of haplotypes found for each taxon ranged from five in Melanelia stygia to 12 in Melanelia hepatizon and Montanelia disjuncta; however, their numbers correlate with the number of specimens tested. New haplotypes for Melanelia agnata, M. hepatizon and Cetraria commixta are found. Based on our 169-sample dataset, we could not infer any geographical correlation, either locally or world-wide. Many of the analysed haplotypes were widely distributed and the same haplotype was often shared between temperate and polar populations. A comparison of molecular, morphological, anatomical and chemical characters also shows no correlation

Phylogenetic relationship of the stringent response-related genes of marine bacteria

Bacteria living in marine environment encounter various challenges and limitations, thus in order to survive, they need to employ efficient stress-response mechanisms. One of these mechanisms is the stringent response, where unusual nucleotides, guanosine tetra- and pentaphosphates, herald starvation and physico-chemical stresses. All so far sequenced free-living bacteria contain the gene(s) responsible for (p)ppGpp synthesis - rsh (named after Escherichia coli genes, relA and spoT). Two similar genes were identified mostly in β- and γ-proteobacteria while other bacteria have only one gene coding the dual function of (p)ppGpp synthesis and degradation. Although the presence of (p)ppGpp-mediated response to the stress conditions has been shown for a few, and predicted for some other marine microorganisms, the (p)ppGpp effects may vary among different organisms. Thus, in this work we asked whether marine bacteria could have evolved a genetic adaptation specifically suited to adapt to environment with limited resources. The phylogenetic analyses of SpoT, RelA and RSH proteins from organisms associated with marine environment showed, however, that the evolutionary correlations obtained for these proteins are congruent with those constructed for 16S rRNA sequences and reflect taxonomical relationships of these organisms. Likewise, the similarity of specific amino acid residues indispensable for catalytic activity of these enzymes is very high, and any observed changes parallel with the taxonomical and evolutionary relationships. However, potential homologs of Mesh1 enzyme (metazoan SpoT homologs) that occur in both eukaryotic and prokaryotic organisms and contain the hydrolytic domain orthologous to SpoT were identified in Cellulophaga, Erythrobacter and Flavobacterium genera for the first time, as well as in soil bacterium Cytophaga hutchinsonii and freshwater Rhodothermus marinus

Morphology and secondary chemistry in species recognition of Parmelia omphalodes group – evidence from molecular data with notes on the ecological niche modelling and genetic variability of photobionts

To evaluate the importance of morphological and chemical characters used in the recognition of species within the Parmelia omphalodes group, we performed phylogenetic, morphological and chemical analyses of 335 specimens, of which 34 were used for molecular analyses. Phylogenetic analyses, based on ITS rDNA sequences, show that P. pinnatifida is distinct from P. omphalodes and the most important difference between those species is the development of pseudocyphellae. In P. pinnatifida, they are mostly marginal and form white rims along lobes margins, but laminal pseudocyphellae can develop in older parts of thalli and are predominantly connected with marginal pseudocyphellae. In contrast, in P. omphalodes laminal pseudocyphellae are common and are predominantly not connected to marginal pseudocyphellae. Chemical composition of secondary lichen metabolites in both analysed species is identical and therefore this feature is not diagnostic in species recognition. Few samples of P. discordans, species morphologically similar to P. omphalodes and P. pinnatifida, were also included in the analyses and they are nested within the clade of P. omphalodes, despite the different chemistry (protocetraric acid present versus salazinic acid in P. omphalodes). All taxa of the P. omphalodes group occupy similar niches, but their potential distributions are wider than those currently known. The absence of specimens in some localities may be limited by the photobiont availability. Parmelia omphalodes and P. pinnatifida are moderately selective in photobiont choice as they form associations with at least two or three lineages of Trebouxia clade S. Parmelia pinnatifida, as well as P. discordans are associated with Trebouxia OTU S02 which seems to have a broad ecological amplitude. Other lineages of Trebouxia seem to be rarer, especially Trebouxia sp. OTU S04, which is sometimes present in P. pinnatifida. This study indicates the importance of extensive research including morphology, chemistry and analysis of molecular markers of both bionts in taxonomical studies of lichens

Photobiont switching causes changes in the reproduction strategy and phenotypic dimorphism in the Arthoniomycetes

Abstract Phylogenetic analyses using mtSSU and nuITS sequences of Buellia violaceofusca (previously placed in Lecanoromycetes), a sterile, sorediate lichen having a trebouxioid photobiont, surprisingly prove that the species is conspecific with Lecanographa amylacea (Arthoniomycetes), a fertile, esorediate species with a trentepohlioid photobiont. These results suggest that L. amylacea and B. violaceofusca are photomorphs of the same mycobiont species, which, depending on the photobiont type, changes the morphology and the reproduction strategy. This is the first example of a lichenized fungus that can select between Trebouxia (Trebouxiophyceae) and trentepohlioid (Ulvophyceae) photobionts. Trebouxia photobionts from the sorediate morphotype belong to at least three different phylogenetic clades, and the results suggest that Lecanographa amylacea can capture the photobiont of other lichens such as Chrysothrix candelaris to form the sorediate morphotype. Phylogenetic analyses based on rbcL DNA data suggest that the trentepohlioid photobiont of L. amylacea is closely related to Trentepohlia isolated from fruticose lichens. The flexibility in the photobiont choice enables L. amylacea to use a larger range of tree hosts. This strategy helps the lichen to withstand changes of environmental conditions, to widen its distribution range and to increase its population size, which is particularly important for the survival of this rare species

Phylogenetic placement of Lepraria cryptovouauxii sp. nov. (Lecanorales, Lecanoromycetes, Ascomycota) with notes on other Lepraria species from South America

Lepraria cryptovouauxii is described as a new semicryptic species similar to L. vouauxii, from which it differs geographically (South America) and phylogenetically; both species differ in nucleotide position characters in nucITS barcoding marker. Lepraria harrisiana is reported as new to South America and L. nothofagi as new to Antarctica, Bolivia, and Peru. Lepraria incana (South American records are referred to L. aff. hodkinsoniana) and L. vouauxii (most South American records are referred to L. cryptovouauxii) should be excluded at least temporarily from the lichen list of South America. All records previously referred to as L. alpina from Bolivia and Peru belong to L. nothofagi. Most of Bolivian records of L. pallida belong to L. harrisiana. Lepraria borealis and L. caesioalba should be included in L. neglecta. Lepraria achariana, L. impossibilis, and L. sipmaniana are sequenced for the first time