Acarospora alba, A. indistincta, A. sharnoffii, and A. tejonensis are described from California. Sarcogyne fasciculata is described from California and New Mexico. Sarcogyne coeruleonigricans is reported new for California. Sarcogyne lapponica is recognized as a synonym of Acarospora lapponica, its basionym. We report 127 described species of Acarosporaceae for North America. We verified 62 species of Acarosporaceae from California.

Autopolyploidy, the result of genome duplication within a single species, is widespread among plant lineages and believed to have played a major role in angiosperm evolution and diversification. Whole genome duplication often triggers significant morphological and ecological changes in autopolyploids vis-a-vis their diploid progenitors, which are induced by subtle changes in gene expression patterns, often of a stochastic nature. Recent results have nonetheless identified specific changes in meiotic, metabolic, and defense response pathways that seem to be commonly shared among autopolyploid species, hinting at convergent evolution. Notably, a set of 12 core meiotic genes, including several genes involved in meiotic crossover formation, has been found to undergo strong selective pressure in the aftermath of autopolyploidization. For the most part these findings have been based on the study of Arabidopsis arenosa and A. lyrata autotetraploids and the question has remained as to whether the evolutionary forces shaping the establishment and evolution of autopolyploidy in the Arabidopsis model system extend more broadly across angiosperms, an area where our knowledge is still limited. In order to address these questions, we conducted a comparative transcriptome analysis of Betula pubescens , a highly introgressed autotetraploid, and its diploid sister species, B. pendula , two birch species belonging to the Fagales order that diverged from Brassicales 120-140 Mya. Our results reveal significant changes in the expression patterns of B. pubescens in genes involved in secondary metabolic processes and the regulation of stress response to pathogens, in agreement with results obtained in other autopolyploid plant complexes. Allele-specific expression analysis identified 16 meiotic genes in B. pubescens with constrained expression patterns, strongly favoring alleles introgressed from B. humilis or B. nana , a set that includes 8 meiotic genes − ASY1 , ASY3 , PDS5B , PRD3 , SYN1 , SMC3, SHOC1 and SCC4 − previously found to be under selection in Arabidopsis autopolyploids. These results provide support to the hypothesis that whole genome duplication triggers similar genomic responses across flowering plants, and that the evolutionary path available to autopolyploids for regaining meiotic stability is highly conserved and dependent on a small group of core meiotic genes. ### Competing Interest Statement The authors have declared no competing interest.

Introgression allows polyploid species to acquire new genomic content from diploid progenitors or from other unrelated diploid or polyploid lineages, contributing to genetic diversity and facilitating adaptive allele discovery. In some cases, high levels of introgression elicit the replacement of large numbers of alleles inherited from the polyploid's ancestral species, profoundly reshaping the polyploid's genomic composition. In such complex polyploids, it is often difficult to determine which taxa were the progenitor species and which taxa provided additional introgressive blocks through subsequent hybridization. Here, we use population-level genomic data to reconstruct the phylogenetic history of Betula pubescens (downy birch), a tetraploid species often assumed to be of allopolyploid origin and which is known to hybridize with at least four other birch species. This was achieved by modeling polyploidization and introgression events under the multispecies coalescent and then using an approximate Bayesian computation rejection algorithm to evaluate and compare competing polyploidization models. We provide evidence that B. pubescens is the outcome of an autoploid genome doubling event in the common ancestor of B. pendula and its extant sister species, B. platyphylla, that took place approximately 178,000-188,000 generations ago. Extensive hybridization with B. pendula, B. nana, and B. humilis followed in the aftermath of autopolyploidization, with the relative contribution of each of these species to the B. pubescens genome varying markedly across the species' range. Functional analysis of B. pubescens loci containing alleles introgressed from B. nana identified multiple genes involved in climate adaptation, while loci containing alleles derived from B. humilis revealed several genes involved in the regulation of meiotic stability and pollen viability in plant species.

The discovery and study of three new species of Trimmatothelopsis from Southwestern North America, T. californica, T. mexicana, and T. novomexicana, adds not only to the diversity of the genus and family but generated new insights into the occurrence of two ascus types in the genus and the variety of conidiogenous cells and conidia. Trimmatothelopsis now includes 15 species with a mainly Holarctic distribution (Asia, Europe, North America) and one species in Australia. A key is supplied to the genus. An overview of the genus Trimmatothelopsis is given, including differentiation from other genera of Acarosporaceae. The monotypic genus Thelocarpella is considered to be a synonym of Trimmatothelopsis. The new combination Trimmatothelopsis wirthii is proposed. The ascus type is shown to be variable in the genus with species with two types being intermixed with each other in our phylogeny.

Sarcogyne pruinosa and S. regularis are revised and lectotypes selected. Sarcogyne pruinosa is recognized as oldest name for the species and S. regularis as a synonym. The description of the species is revised. Sarcogyne pruinosa does not occur in North America. Two new species are described, Sarcogyne nimisii from Italy and Sarcogyne belarusensis from Belarus, Germany and Italy. Sarcogyne platycarpoides is lectotypified and S. melaniza is recognized as its synonym. New records are reported of S. distinguenda and S. nivea from the Czech Republic and Italy and S. fallax from the Czech Republic. A key is supplied for 14 species of Sarcogyne on calcareous rock in Europe.

Abstract. Eight new species are described from the Chihuahuan Desert in southern New Mexico: Acarospora agostiniana, A. divisa, A. fissurata, A. ryanii, Sarcogyne brouardiana, S. coeruleonigricans, S. malpaiensis, and S. nogalensis. Three species, Acarospora coloradiana, A. peltastica, and A. utahensis are not treated as synonyms of A. strigata, a South American endemic. Thirty-four species of Acarosporaceae are reported from the Chihuahuan Desert in southern New Mexico. Fifty-six species of Acarosporaceae are reported from New Mexico. It is estimated that 416 species of described Acarosporales occur worldwide, most in need of revisions. Including species described or taken out of synonymy in this paper, there are 120 species of Acarosporaceae reported from North America north of Mexico. Caeruleum heppii is not a member of the Acarosporales. A key is supplied for 93 species of Acarosporaceae in the southwestern United States (Arizona, southern and central California, Nevada, New Mexico, Utah, and western Texas), which covers 77.5% of the described species in North America. Resumen. En este trabajo se describen ocho nuevas especies del desierto de Chihuahua en el sur de Nuevo México: Acarospora agostiniana, A. divisa, A. fissurata, A. ryanii, Sarcogyne brouardiana, S. coeruleonigricans, S. malpaiensis y S. nogalensis, y tres especies Acarospora coloradiana, A. peltastica y A. utahensis, que no con tratadas como sinónimos de A. strigata, una especie endémica de América del Sur. Además, se reportan 34 especies de Acarosporaceae en el desierto de Chihuahua en el sur de Nuevo México y 56 especies de Acarosporaceae en Nuevo México. Se estima que 416 especies de Acarosporales has sido descritas en el mundo, la mayoría de las cuales necesita revisión. Incluyendo las especies descritas o eliminadas de la sinonimia en este trabajo, hay 120 especies de Acarosporaceae reportadas de Norteamérica al norte de México. Caeruleum heppii no es miembro de las Acarosporales. Finalmente, se proporciona una clave para 93 especies de Acarosporaceae en el suroeste de los Estados Unidos (Arizona, sur y centro de California, Nevada, Nuevo México, Utah, y el oeste de Texas), cubriendo el 77.5% de las especies descritas en América del Norte.

A history of the study of Sarcogyne is explained. Acarospora and Sarcogyne are morphological genus concepts and neither are currently recovered as monophyletic clades. Neither genus has any synapomorphic character or suite of characters distinguishing all species as either Sarcogyne or Acarospora. Three new species are described from Europe and North America: Sarcogyne adscendens (California, U.S.A.), S. lecanorina (Czech Republic), and S. poeltii (Greece). Two sterile taxa with probably functionally infertile apothecia were recovered in the Acarospora badiofusca-A. cervina clade, S. kisonii nom. prov. (Germany), and S. schultzii nom. prov. (Austria). They could replicate by division and fragmentation and S. kisonii also produces conidia. We report Sarcogyne canadensis new for Romania and Europe and Sarcogyne oceanica new for Germany. Acarospora glaucocarpa var. cumulata is a synonym of S. praetermissa. Sequences of nine undescribed Sarcogyne taxa from North America and one from Czech Republic, all known from single collections, are made available for future research.

Acarospora schorica is the oldest name for Trimmatothelopsis sphaerosperma and has priority. The new combination Trimmatothelopsis schorica is proposed. The species is recognized as occurring in Asia, Europe, and North America. Phylogenetic analysis of sequence data verifies its placement in the genus Trimmatothelopsis.

Non-coding repetitive DNA (repeatome) is an active part of the nuclear genome, involved in its structure, evolution and function. It is dominated by transposable elements (TEs) and satellite DNA and is prone to the most rapid changes over time. The TEs activity presumably causes the global genome reorganization and may play an adaptive or regulatory role in response to environmental challenges. This assumption is applied here for the first time to plants from the Cape Floristic hotspot to determine whether changes in repetitive DNA are related to responses to a harsh, but extremely species-rich environment. The genus Pteronia (Asteraceae) serves as a suitable model group because it shows considerable variation in genome size at the diploid level and has high and nearly equal levels of endemism in the two main Cape biomes, Fynbos and Succulent Karoo. First, we constructed a phylogeny based on multiple low-copy genes that served as a phylogenetic framework for detecting quantitative and qualitative changes in the repeatome. Second, we performed a comparative analysis of the environments of two groups of Pteronia differing in their TEs bursts. Our results suggest that the environmental transition from the Succulent Karoo to the Fynbos is accompanied by TEs burst, which is likely also driving phylogenetic divergence. We thus hypothesize that analysis of rapidly evolving repeatome could serve as an important proxy for determining the molecular basis of lineage divergence in rapidly radiating groups.

A phylogenetic analysis recovered Acarospora oreophila in the monophyletic Trimmatothelopsis clade and a new combination was made. Trimmatothelopsis oreophila is closely related to T. terricola. Acarospora benedarensis and A. sphaerosperma are transferred to Trimmatothelopsis based on morphological and anatomical analyses. Globose apothecia with the disc usually less 0.5 mm in diam., a high hymenium, narrow paraphyses, and long conidia (3-6 x 1-1.5 mu m) are diagnostic characters of the genus. Five species occur in North America.

Abstract: Knudsen, K., Kocourková, J., Hodková, E. & Schiefelbein, U. 2021. A new species of Myriospora (Acarosporaceae) and a report of Myriospora rufescens from Central Europe. – Herzogia 34: 327–338. Myriospora bullata is described from Germany. It is similar to M. scabrida in having apothecia in a parathecial ring but differs in becoming bullate, in often being orange, and in being a lichenicolous lichen. It is probably restricted to copper-rich rock. Myriospora himalayensis is not considered a member of the genus but a regional lineage in either Acarospora or Sarcogyne. Myriospora rufescens is reported new for the Czech Republic.

Eighteen described Acarosporaceae are reported from the Chihuahuan Desert in southern New Mexico. Ten species reported by Magnusson from northern New Mexico were collected in the Chihuahuan Desert. Four species described by Magnusson are revised and taken out of synonymy: Acarospora amabilis, A. applanata, A. carnegiei and A. tenebrica. The squamulose yellow species A. organensis, new for science, was determined as A. xanthophana by Magnusson, a species endemic to South America. Acarospora organensis differs in having a higher hymenium than the two common and similar squamulose species, A. socialis from coastal Mexico and California and A. radicata from the New Mexican, Mojave and Sonoran Deserts. Acarospora subcontigua is reported new for North America.

The centre–periphery hypothesis (CPH) predicts a decrease in population performance from the centre of the species range towards the edge, hindering further species expansion. To overcome ecological limitation, local adaptation of peripheral populations is assumed necessary to extend niche space and thus to potentially facilitate species’ range expansion. However, adaptive changes do not necessarily correspond to current ecological marginality. Instead, population history may provide a fuller context for understanding patterns of local adaptation within the species range. Here, we test whether local adaptation to current conditions or population history explains current species distribution in an annual heterocarpic species, Atriplex tatarica, in Europe. The ecological marginality and population history were estimated using species distribution modelling (SDM) and 13 microsatellite markers. To test for local adaptation, we evaluated the population performance of both currently central and currently peripheral populations by examining germination and growth traits under three temperature regimes which correspond to climates within, and also beyond, the species’ current range. In addition, we compared Bayesian estimates of population differentiation in neutral genetic markers and quantitative traits to test whether phenotypic differentiation evolved by local adaptation and/or by genetic drift. We found population performances were not higher under temperature regimes corresponding to their own habitats, suggesting that patterns of local adaptation in A. tatarica do not correspond to current centre–periphery gradient. In contrast, population genetic structure indicated a strong influence of population history on variation in the germination phenotype. Species distribution modelling suggested a more cold–tolerant genetic lineage was located at the species' range periphery during the last glacial period. Meanwhile, a less cold‐tolerant lineage occurred in more suitable areas of the Balkan Peninsula and southeastern Europe. Thus, the strong adaptive divergence of evolutionary lineages may reflect a past spatial arrangement of populations, suggesting evolutionary processes were ongoing before the species expansion in the Holocene. Synthesis . There is continuing debate concerning the speed of trait evolution during range expansion with climate change. Our results indicate that even though organisms expand rapidly, the accompanying evolutionary changes in phenotype may be much slower.

Aim The Holocene history of annual plant species is at best shadowy because, for most, the palaeobotanical data are scarce or absent. Hence, there is limited information on their glacial refugia and postglacial colonization pathways. Also, little is known on how human activity has affected their expansion. Here, we outline the joint influences of postglacial colonization and recent expansions on the genetic diversity of the continental, sub-halophyte species Atriplex tatarica during the late Pleistocene and the Holocene. Location Europe. Taxon Atriplex tatarica (Amaranthaceae). Methods We analysed 780 individuals from 80 populations throughout the current European distribution range, employing chloroplast DNA sequences and microsatellite markers. Results Five haplotype lineages were recognized based on the results of the cpDNA phylogenetic analyses. These lineages originated 0.43-0.22 myr BP. Bayesian clustering analyses divided populations of A. tatarica into two clusters: (a) populations in the Pannonian Basin and the Bohemian Massif and (b) populations in the North European Plain, the Balkan Peninsula, the Carpathian Arc and the Pontic region. The ABC approach provided the strongest statistical support for a model proposing refugia in the Balkan Peninsula and the Pannonian Basin. Expansions from these refugia occurred around 7,000 yr BP. Main conclusion Atriplex tatarica represents a continental species growing exclusively in man-made habitats. It serves as a phylogeographic model for annual ruderal taxa currently spreading in central Europe along highways and representing a large group of alien plant species, the so-called archaeophytes. Atriplex tatarica survived the last glaciation in both a southerly located Balkan refugium and in a more northerly refugium in the Pannonian Basin. From these, the species has colonized Europe as a result of expansion of humans and the anthropogenic climate change. The massive colonization of central north Europe is very recent, with the expansion estimated to have occurred only hundreds of years ago.

The presence and extent of hybridization within the Chenopodium album aggregate (Amaranthaceae) is still unclear. Although many hybrid combinations have been described, their existence in the field has never been systematically studied and verified. The main aim of this study was to ascertain the extent of interspecific hybridization between the diploid species C. ficifolium and C. suecicum using highly variable nuclear microsatellite markers. Due to the absence of such kind of molecular markers for the whole C . album group, we divided the analysis into two steps: (1) Eleven microsatellite loci designed for the closely related species C. quinoa were cross-amplified in five Eurasian species of the C . album diploid–polyploid complex, i.e. C . album s.s. (6x), C . striatiforme (4x), C . strictum (4x), C . ficifolium (2x) and C . suecicum (2x); (2) For the detection of interspecific hybridization between C . ficifolium and C . suecicum, we sampled 480 individuals from five localities in Central Europe. We also investigated morphological differences between the parental taxa and their hybrid and devised a key for their determination. Analysis of variation in microsatellite loci using Bayesian methods, PCoA and Neighbour-joining tree identified 32 F1 hybrids. These F1 hybrids, described here as C . paradoxum Mandák, formed a cluster between well-differentiated parental species, combining the morphological characters of both their parents. Moreover, genetic analyses also recognized several F2 or backcross hybrids, whose delimitation, mainly from C. suecicum and F1 hybrids, based on morphological characters, is problematic.