Stanislav Španiel

Derived woodiness—the evolution of woody growth from herbaceous ancestors—has arisen hundreds of times across flowering plants, yet the environmental conditions associated with its repeated evolution remain poorly understood. Here, we analyse woodiness evolution in the mustard family (Brassicaceae; ∼4,150 species) using a time-calibrated phylogeny of 2,927 species, including 374 of the 385 known woody species, together with global growth-form and climatic niche data. We infer 231 independent origins of woodiness alongside 176 reversals to herbaceousness, indicating that woodiness evolves repeatedly but remains evolutionarily unstable. Although woody species are enriched on islands, most occur on the mainland, where woodiness is consistently associated with drought and reduced frost. Correlated-evolution analyses reveal that drought is associated primarily with the persistence of woodiness, whereas reduced frost is associated with gains of woodiness and increased frost with its loss. These findings identify distinct climatic associations with the gain, persistence, and loss of woody growth forms.

Two perennial goldenrods, Solidago canadensis and S. gigantea (Asteraceae), are considered successful plant invaders with an exceptional ability to affect the biodiversity and environment of native ecosystems in Europe. However, their species-specific invasion impacts and associated ecological mechanisms shaping the species diversity of plant guilds and the soil conditions in grasslands remain poorly understood. Here, a spatial invasion-gradient approach with different invasion levels categorised by the percentage of goldenrod cover (heavily invaded > 50%, transitional invaded 20–50% and uninvaded control plots) was used to assess invasion impacts on species diversity of forbs, graminoids and bryophytes as well as on soil and vegetation properties in semi-natural grasslands of Slovakia (Central Europe). Multi-guild diversity assessment showed that graminoids were more tolerant than forbs of the competitive and stressful conditions in invaded plots. Invasion level reduced species richness of forbs in heavily invaded plots, likely owing to intensified competition and litter accumulation generated by dense Solidago stands. No invasion effect was found on graminoid and bryophyte species diversity metrics. Most variation in species diversity and ecological responses was addressed to the shared invasion impacts of both Solidago species, but several species-specific invasion effects on forb diversity indices and soil chemistry (soil reaction, nitrogen and potassium concentrations, C-to-N ratio) were also identified. The contrasting forb responses in Shannon and Simpson diversity indices corresponded to shifts in community evenness associated with species-specific effects of the invaders on soil nutrient cycling and productivity. Goldenrod invasions also altered community structure, primarily through shifts in abundance-dominance interactions rather than through substantial species replacement. Our results highlight the importance of recording invasion impacts across functional guilds and ecosystem components to better understand the mechanisms of plant invasion in semi-natural grasslands.

Author information: KMa, https://orcid.org/0000-0002-7658-0844; JK, https://orcid.org/0000-0002-9983-7630; RGA, https://orcid.org/0009-0000-0176-7252; JČ, https://orcid.org/0000-0002-2370-2051; AHE, https://orcid.org/0000-0002-7930-5696; SVG, https://orcid.org/0000-0002-7678-9648; AGG, https://orcid.org/0000-0002-4580-2061; AVH, https://orcid.org/0009-0009-4791-3919; IH, https://orcid.org/0000-0002-9905-381X; ZHH, https://orcid.org/0000-0001-8880-2144; IJ, https://orcid.org/0000-0003-2105-5310; TK, –; EK, https://orcid.org/0000-0001-9641-5750; FK, https://orcid.org/0000-0002-8793-7992; CL, https://orcid.org/0000-0002-2450-5455; TM, https://orcid.org/0000-0001-6485-0563; KMa, https://orcid.org/0000-0002-7658-0844; LYuM, https://orcid.org/0000-0001-9385-6462; LM, https://orcid.org/0000-0003-4478-5930; LAM, https://orcid.org/0000-0002-1283-3865; KMu, https://orcid.org/0000-0003-1585-6226; YMN, https://orcid.org/0000-0003-4749-0839; AAN, https://orcid.org/0000-0002-4380-7715; MN, https://orcid.org/0000-0002-1594-2418; AP, https://orcid.org/0000-0003-3620-6695; AVP, https://orcid.org/0009-0004-3522-5936; PP, https://orcid.org/0000-0001-8500-442X; BŠ, https://orcid.org/0000-0002-6487-6373; KS, https://orcid.org/0000-0002-1452-5428; MŠ, https://orcid.org/0000-0002-5919-890X; SŠ, https://orcid.org/0000-0003-4809-4379; GŠ, https://orcid.org/0000-0002-7439-2911; EZ, https://orcid.org/0000-0003-2992-2941; JZ‐L, https://orcid.org/0000-0002-8950-6643

The taxonomic identity of Alyssum emarginatum, an overlooked species described by Visiani from present-day Croatia, is assessed on the basis of Visiani’s herbarium material and the protologue. Other plant specimens collected in Croatia, including the original locality, were examined as well. The lectotype of the name is designated and it is identified as a new synonym of Alyssum simplex.

Background and aims: Invasive species represent a threat to the conservation of biological systems. Riparian ecosystems are vulnerable to plant invasions, as waterflow facilitates the dispersal of plant propagules, while invasive species may subsequently impact soil, including soil microbial communities. Downstream connectivity among disparate riverine segments is expected to cause spatial continuity of abiotic and biotic components of riparian ecosystems. Methods: We studied diversity of microbial communities in three headwater streams in Central Europe. Plant diversity, soil properties and soil microbiota were assessed on 20 sample plots per river. Soil microbial activity and community-level physiological profiling were used to study the soil microbial community. Results: While the α-diversity of plants and soil microbiota was similar among rivers, plant communities were substantially more differentiated than microbial communities. Richness in alien and invasive plants significantly differed among rivers, which was reflected in different spatial patterns of microbial activity and diversity. A high level of spatial continuity was observed in the Kysuca river with straightened riverbed and artificial surfaces in the adjacent areas. The cover of invasive plants affects the composition of microbial functional groups of riverbed soils. Conclusion: The expectation of spatial continuity of riverbed soil properties including those of soil microbiota caused by connectivity between different river segments was only partially fulfilled. Spatial continuity strongly depends on the environmental setting and stream characteristics of a particular river. The presence of invasive herbs affected the functional composition of soil microbiota but had no effect on microbial activity and diversity.

Aim: New areas are often simultaneously invaded by closely related alien species; however, between‐species differences in the course of their invasive spreading due to diverse ecological preferences have rarely been investigated. Here, we aim to study the species‐specific spatio‐temporal invasion patterns of Solidago canadensis and S. gigantea.Location: Slovakia—the Western Carpathian and adjacent Pannonian regions.Taxon: Invasive alien Solidago canadensis and S. gigantea.Methods: Our study was based on revised herbarium specimens, a recent field survey which included gathering abundance and habitat data, and environmental data from GIS layers. We characterised the environmental niche differentiation between S. canadensis and S. gigantea. Generalised additive models were then used to identify the key drivers of the species' occurrences and to assess their potential current and future distributions.Results: Both species began to spread in Slovakia in the 1850s; in the first 100 years, the number of S. gigantea sites increased exponentially, while that of S. canadensis remained low. Currently, S. canadensis is more widespread in the region. The species have similar habitat preferences. Their environmental niches overlap, but are not identical. The core distribution of S. canadensis is in foothills and valleys that experience lower annual mean temperatures, while that of S. gigantea is in lowlands with higher annual mean temperatures. A large part of their potential distribution areas seems to be already invaded. Possible future climate change could stimulate the spreading of S. canadensis into higher altitudes and S. gigantea farther into lowlands and Carpathian foothills.Main conclusions: The studied invasive Solidago species differed considerably in the early stages of invasion. Their environmental niches, current realised and potential distribution patterns are different. In the studied region, further spreading, with an increase in the number and size of populations, is likely unless effective measures are undertaken.

Alyssum rossetii is recorded for the first time in Spain from a single locality in the Pyrenees. After the type locality in the Valpelline valley (Pennine Alps, Italy), it is only the second known locality of this species. Morphology, diploid chromosome number (2n = 16), relative genome size, and ITS sequences confirm that the Pyrenean plants are conspecific with the Alpine ones and should be classified as A. rossetii. Phylogenetic analyses placed A. rossetii within the clade of A. sect. Gamosepalum comprising species from Turkey and demonstrated that A. rossetii is only distantly related to other Alyssum species occurring in the Pyrenees and adjacent regions: A. alyssoides, A. cacuminum, A. collinum, A. fastigiatum, A. granatense, A. montanum, and A. simplex. An identification key to all Alyssum species known from the Pyrenees is presented. Citation: Š aniel S Mártonfiová L & Zozomová-Lihová J 2024: An unex ected occurrence of Al ssum rossetii (Brassicaceae) in the Pyrenees, a new species for the Spanish flora. – Willdenowia 53: 297–307 Version of record first published online on 29 January 2024.

Elucidating the evolution of recently diverged and polyploid-rich plant lineages may be challenging even with high-throughput sequencing, both for biological reasons and bioinformatic difficulties. Here, we apply target enrichment with genome skimming (Hyb-Seq) to unravel the evolutionary history of the Alyssum montanum-A. repens species complex. Reconstruction of phylogenetic relationships in diploids supported recent and rapid diversification accompanied by reticulation events. Of the four main clades identified among the diploids, three clades included species from the Alps, Apennine and Balkan peninsulas, indicating close biogeographic links between these regions. We further focused on the clade distributed from the Western Alps to the Iberian Peninsula, which comprises numerous polyploids as opposed to a few diploids. Using a recently developed PhyloSD (phylogenomic subgenome detection) pipeline, we successfully tracked the ancestry of all polyploids. We inferred multiple polyploidization events that involved two closely related diploid progenitors, resulting into several sibling polyploids: two autopolyploids and six allopolyploids. The skewed proportions of major homeolog-types and the occurrence of some minor homeolog-types, both exhibiting geographic patterns, suggest introgression with the progenitors and other related diploids. Our study highlights a unique case of parallel polyploid speciation that was enhanced by ecological and geographic separation and provides an excellent resource for future studies of polyploid evolution.