Over time, mountain biota has undergone complex evolutionary histories that have left imprints on its genomic arrangement, geographical distribution and diversity of contemporary lineages. Knowledge on these biogeographical aspects still lags behind for invertebrates inhabiting the Alpine region. In the present study, we examined three scorpion species of the subgenus Euscorpius (Alpiscorpius) from the European Alps using cytogenetic and molecular phylogenetic approaches to determine the variation and population structure of extant lineages at both chromosome and genetic level, and to provide an insight into the species diversification histories. We detected considerable intraspecific variability in chromosome complements and localization of the 18S rDNA loci in all studied species. Such chromosome differences were noticeable as the existence of three [in E. (A.) alpha and E. (A.) germanus] or four [in E. (A.) gamma] range-restricted karyotypic races. These races differed from one another either by 2n [in E. (A.) alpha 2n = 54, 60, 90; in E. (A.) gamma 2n = 58, 60, 88, 86-92], or by the karyotypic formula [in E. (A.) germanus 2n = 34m + 12sm; 36m + 10sm; 42m + 4sm]. Using mitochondrial (16S rRNA, COI) and nuclear (28S rDNA) genetic markers, we examined genetic variation and reconstructed phylogenetic relationships among the karyotypic races. Both approaches provided evidence for the existence of ten deeply divergent lineages exhibiting the features of local endemics and indicating the presence of cryptic species. Molecular dating analyses suggest that these lineages diversified during the Plio-Pleistocene and this process was presumably accompanied by dynamic structural changes in the genome organization.

• Klíčová slova
• Alps, Cryptic species, Evolution, Karyotype evolution, Phylogeography, Species delimitation,
• MeSH
• alely MeSH
• časové faktory MeSH
• chromozomy genetika   MeSH
• druhová specificita MeSH
• fylogeneze MeSH
• genetická variace * MeSH
• genom MeSH
• karyotypizace MeSH
• molekulární evoluce * MeSH
• ribozomální DNA genetika   MeSH
• RNA ribozomální 16S genetika   MeSH
• štíři genetika   MeSH
• zeměpis MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ribozomální DNA MeSH
• RNA ribozomální 16S MeSH

With the increasing application of molecular techniques for diatom species discovery and identification, it is important both from a taxonomic as well as an ecological and applied perspective, to understand in which groups morphological species delimitation is congruent with molecular approaches, or needs reconsideration. Moreover, such studies can improve our understanding of morphological trait evolution in this important group of microalgae. In this study, we used morphometric analysis on light microscopy (LM) micrographs in SHERPA, detailed scanning electron microscopy (SEM), and cytological observations in LM to examine 70 clones belonging to eight distinct molecular lineages of the cosmopolitan terrestrial diatom Pinnularia borealis. Due to high within-lineage variation, no conclusive morphological separation in LM nor SEM could be detected. Morphological stasis due to the "low-morphology" problem or stabilizing selection, as well as parallel/convergent evolution, phenotypic plasticity and structural inheritance are discussed as potential drivers for the observations. Altogether, P. borealis is truly cryptic, in contrast to the majority of other diatom species complexes which turned out to be pseudo-cryptic following detailed morphological analysis.

• Klíčová slova
• Diatoms, LSU rDNA, molecular phylogenies, morphometrics, rbcL, shape.,
• MeSH
• biodiverzita * MeSH
• mikroskopie elektronová rastrovací MeSH
• mikroskopie MeSH
• rozsivky klasifikace   ultrastruktura   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Identifying factors that influence species interactions is central to research in symbiotic systems. While lichens represent iconic models of symbiosis and play important roles in understanding the biology of symbiotic interactions, patterns of interactions in lichen symbionts and mechanisms governing these relationships are not well characterized. This is due, in part to the fact that current taxonomic approaches for recognizing diversity in lichen symbionts commonly fail to accurately reflect actual species diversity. In this study, we employed DNA-based approaches to circumscribed candidate species-level lineages in rock-posy lichen symbionts (mycobiont=Rhizoplaca s. lat. species; photobiont=Trebouxia species). Our results revealed a high degree of cryptic diversity in both the myco- and photobionts in these lichens. Using the candidate species circumscribed here, we investigated the specificity of the symbionts toward their partners and inferred the relative importance of various factors influencing symbiont interactions. Distinct mycobiont species complexes, ecozones, and biomes are significantly correlated with the occurrence of photobiont OTUs, indicating that complex interactions among mycobiont lineages, ecogeography, and microhabitat determine interactions between photobionts and their mycobionts in lichen symbiosis. One-to-one specificity between mycobiont and photobiont species was not found, with the exception of R. maheui that associated with a single Trebouxia OTU that was not found with other Rhizoplaca s. lat. species. We estimated the most recent common ancestor of the core Rhizoplaca group at c. 62.5Ma, similar in age to the diverse parmelioid core group in the well-studied family Parmeliaceae. However, in contrast to Parmeliaceae, species in Rhizoplaca were found to associate with a narrow range of photobionts. Our study provides important perspectives into species diversity and interactions in iconic lichen symbiotic systems and establishes a valuable framework for continuing research into rock-posy lichens.

• Klíčová slova
• Ecoregion, Lecanoraceae, Selectivity, Specificity, Symbiosis, Trebouxia,
• MeSH
• biodiverzita MeSH
• Chlorophyta klasifikace   fyziologie   MeSH
• DNA fungální chemie   izolace a purifikace   metabolismus   MeSH
• fylogeneze MeSH
• lišejníky klasifikace   genetika   fyziologie   MeSH
• sekvenční analýza DNA MeSH
• symbióza * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DNA fungální MeSH

High elevation temperate mountains have long been considered species poor owing to high extinction or low speciation rates during the Pleistocene. We performed a phylogenetic and population genomic investigation of an emblematic high-elevation plant clade (Androsace sect. Aretia, 31 currently recognized species), based on plant surveys conducted during alpinism expeditions. We inferred that this clade originated in the Miocene and continued diversifying through Pleistocene glaciations, and discovered three novel species of Androsace dwelling on different bedrock types on the rooftops of the Alps. This highlights that temperate high mountains have been cradles of plant diversity even during the Pleistocene, with in-situ speciation driven by the combined action of geography and geology. Our findings have an unexpected historical relevance: H.-B. de Saussure likely observed one of these species during his 1788 expedition to the Mont Blanc and we describe it here, over two hundred years after its first sighting.

• MeSH
• biodiverzita * MeSH
• fylogeneze MeSH
• nadmořská výška * MeSH
• rostliny * MeSH
• zeměpis MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Taxa of microbial eukaryotes defined on morphological basis display a large degree of genetic diversity, implying the existence of numerous cryptic species. However, it has been postulated that genetic diversity merely mirrors accumulation of neutral mutations. As a case taxon to study cryptic diversity in protists, we used a widely distributed filamentous genus, Klebsormidium, specifically the lineage E (K. flaccidum/K. nitens complex) containing a number of morphologically similar strains. Fourteen clades were recognized in the phylogenetic analysis based on a concatenated ITS rDNA + rbcL data set of more than 70 strains. The results of inferred character evolution indicated the existence of phylogenetic signal in at least two phenotypic characters (production of hydro-repellent filaments and morphology of zoosporangia). Moreover, the lineages recovered exhibited strong ecological preferences to one of the three habitat types: natural subaerial substrata, artificial subaerial substrata, and aquatic habitats. We interpret these results as evidence of existence of a high number of cryptic species within the single morphospecies. We consider that the permanent existence of genetically and ecologically well-defined cryptic species is enabled by the mechanism of selective sweep.

• Klíčová slova
• Algae, cryptic diversity, ecotype, speciation, species concept,
• MeSH
• ekologie * MeSH
• fylogeneze MeSH
• genetická variace genetika   MeSH
• ribozomální DNA genetika   MeSH
• Streptophyta klasifikace   genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ribozomální DNA MeSH

The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on ∼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.

• Klíčová slova
• Conservation, Freshwater mussels, Phylogeography, Unionida,
• MeSH
• fylogeneze MeSH
• fylogeografie MeSH
• genetická variace MeSH
• mitochondriální DNA genetika   MeSH
• Unio * genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• mitochondriální DNA MeSH

South-east Europe, along with the adjacent region of south-west Asia, is an important biodiversity hotspot with high local endemism largely contributed by contemporary continental lineages that retreated to southern refugia during colder Quaternary periods. We investigated the genetic diversity of the European bitterling fish (Rhodeus amarus) species complex (Cyprinidae) across its range in the western Palearctic, but with a particular emphasis in the region of Balkan, Pontic and Caspian refugia. We genotyped 12 polymorphic microsatellite loci and a partial sequence of mitochondrial gene cytochrome b (CYTB) for a set of 1,038 individuals from 60 populations. We used mtDNA sequences to infer phylogenetic relationships and historical demography, and microsatellite markers to describe fine-scale genetic variability and structure. Our mtDNA analysis revealed six well-supported lineages, with limited local co-occurrence. Two lineages are distributed throughout central and western Europe (lineages "A" and "B"), with two zones of secondary contact. Another two lineages were restricted to the Ponto-Aegean region of Greece (lineages "C" and "D") and the final two lineages were restricted south of the Caucasus mountains (lineage "E" from the Black Sea watershed and lineage "F" from the Caspian watershed). A signal of recent expansion was revealed in the two widespread lineages and the Ponto-Aegean lineage "C". The geographic distribution of clusters detected by nuclear microsatellites corresponded well with mitochondrial lineages and demonstrated finely sub-structured populations. A profound population structure suggested a significant role of genetic drift in differentiation among lineages. Lineage divergence in the Ponto-Aegean and Caspian regions are substantial, supporting the validity of two described endemic species (Rhodeus meridionalis as lineage "D" and Rhodeus colchicus as lineage "E") and invite taxonomic evaluation of the other two southern lineages (Thracean "C" and Caspian "F").

• Klíčová slova
• Balkan refugium, Cyprinidae, Gene flow, Genetic drift, Mediterranean endemism, Ponto-Caspian region,
• MeSH
• biodiverzita MeSH
• Cyprinidae klasifikace   genetika   MeSH
• cytochromy b genetika   MeSH
• demografie MeSH
• fylogeneze MeSH
• genetická variace MeSH
• genetický drift MeSH
• genotyp MeSH
• mikrosatelitní repetice MeSH
• mitochondriální DNA chemie   MeSH
• mitochondrie genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• západní Asie MeSH
• Názvy látek
• cytochromy b MeSH
• mitochondriální DNA MeSH

We believe this study is the first attempt to address molecular prospecting for species diversity of Diplostomum (Digenea: Diplostomidae) in Europe. A database linking sequences from the barcode region of the cytochrome c oxidase subunit 1 (cox1) mitochondrial gene and from the internal transcribed spacer cluster (ITS1-5.8S-ITS2) of the rRNA gene was generated for larval and adult parasites of snails, fish and gulls from central Europe. Analyses of the novel cox1 dataset revealed the presence of six genetically distinct Diplostomum lineages in the snail and fish populations studied in the River Ruhr drainage (Germany). ITS1-5.8S-ITS2 sequences from a representative subset of isolates supported the delineation detected by cox1. Molecular elucidation of the life-cycles of Diplostomum spathaceum and Diplostomum pseudospathaceum in central Europe was achieved by matching multiple sequences for isolates from natural infections in snails, fish and birds identified on the basis of the morphology of all life-cycle stages. Comparative analyses restricted to the ITS1 rDNA region and incorporating sequences for six European and seven North American Diplostomum spp. retrieved from GenBank, corroborated the results of the molecular prospecting based on the cox1 dataset. Taken together, these analyses depicted 20 molecularly characterised species and lineages of Diplostomum including three complexes of genetically distinct lineages i.e. 'Diplostomum mergi', 'Diplostomum baeri' and 'Diplostomum huronense', that require further appraisal with the application of molecular, morphological and experimental approaches. Two of the species and 10 of the lineages (arguably species) delineated in the datasets studied originate from central and northern Europe thus indicating a substantial unrecognized genetic diversity inferred from molecular evidence on Diplostomum spp. in Europe.

• MeSH
• cyklooxygenasa 1 genetika   MeSH
• fylogeneze MeSH
• genetická variace * MeSH
• mezerníky ribozomální DNA genetika   MeSH
• molekulární sekvence - údaje MeSH
• sekvenční analýza DNA MeSH
• shluková analýza MeSH
• stadia vývoje MeSH
• Trematoda klasifikace   genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• Severní Amerika MeSH
• Názvy látek
• cyklooxygenasa 1 MeSH
• mezerníky ribozomální DNA MeSH

It is normally supposed that populations of the same species should evolve shared mechanisms of adaptation to common stressors due to evolutionary constraint. Here, we describe a system of within-species local adaptation to coastal habitats, Brassica fruticulosa, and detail surprising strategic variability in adaptive responses to high salinity. These different adaptive responses in neighboring populations are evidenced by transcriptomes, diverse physiological outputs, and distinct genomic selective landscapes. In response to high salinity Northern Catalonian populations restrict root-to-shoot Na+ transport, favoring K+ uptake. Contrastingly, Central Catalonian populations accumulate Na+ in leaves and compensate for the osmotic imbalance with compatible solutes such as proline. Despite contrasting responses, both metapopulations were salinity tolerant relative to all inland accessions. To characterize the genomic basis of these divergent adaptive strategies in an otherwise non-saline-tolerant species, we generate a long-read-based genome and population sequencing of 18 populations (nine inland, nine coastal) across the B. fruticulosa species range. Results of genomic and transcriptomic approaches support the physiological observations of distinct underlying mechanisms of adaptation to high salinity and reveal potential genetic targets of these two very recently evolved salinity adaptations. We therefore provide a model of within-species salinity adaptation and reveal cryptic variation in neighboring plant populations in the mechanisms of adaptation to an important natural stressor highly relevant to agriculture.

• Klíčová slova
• Brassicaceae, adaptation, evolution, population genomics, salinity,
• MeSH
• Brassica * genetika   fyziologie   metabolismus   MeSH
• ekosystém MeSH
• fyziologická adaptace * genetika   MeSH
• genetická variace MeSH
• genom rostlinný MeSH
• regulace genové exprese u rostlin MeSH
• salinita * MeSH
• sodík metabolismus   MeSH
• tolerance k soli genetika   MeSH
• transkriptom MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• sodík MeSH

The decline of amphibian populations, particularly frogs, is often cited as an example in support of the claim that Earth is undergoing its sixth mass extinction event. Amphibians seem to be particularly sensitive to emerging diseases (e.g., fungal and viral pathogens), yet the diversity and geographic distribution of infectious agents are only starting to be investigated. Recent work has linked a previously undescribed protist with mass-mortality events in the United States, in which infected frog tadpoles have an abnormally enlarged yellowish liver filled with protist cells of a presumed parasite. Phylogenetic analyses revealed that this infectious agent was affiliated with the Perkinsea: a parasitic group within the alveolates exemplified by Perkinsus sp., a "marine" protist responsible for mass-mortality events in commercial shellfish populations. Using small subunit (SSU) ribosomal DNA (rDNA) sequencing, we developed a targeted PCR protocol for preferentially sampling a clade of the Perkinsea. We tested this protocol on freshwater environmental DNA, revealing a wide diversity of Perkinsea lineages in these environments. Then, we used the same protocol to test for Perkinsea-like lineages in livers of 182 tadpoles from multiple families of frogs. We identified a distinct Perkinsea clade, encompassing a low level of SSU rDNA variation different from the lineage previously associated with tadpole mass-mortality events. Members of this clade were present in 38 tadpoles sampled from 14 distinct genera/phylogroups, from five countries across three continents. These data provide, to our knowledge, the first evidence that Perkinsea-like protists infect tadpoles across a wide taxonomic range of frogs in tropical and temperate environments, including oceanic islands.

• Klíčová slova
• alveolates, emerging disease, frog decline, molecular diversity, parasite,
• MeSH
• Alveolata klasifikace   patogenita   MeSH
• druhová specificita MeSH
• fylogeneze MeSH
• larva klasifikace   parazitologie   MeSH
• obojživelníci klasifikace   růst a vývoj   MeSH
• zeměpis * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH