The recently observed massive reorganisations of macroinvertebrate assemblages in streams are usually attributed to the combined effects of changes in water quality and climate. The consequences of the associated functional changes for ecosystem services and future development are still unknown. In this study, we try to disentangle the effects of climate change on the functional structure from other anthropogenic effects. To do so, we examine functional richness and composition of biological traits in macroinvertebrate assemblages, coming from 65 near-natural streams in the Czech Republic, where anthropogenic stressors apart from those due to climate change were minimal. We sampled the macroinvertebrates using a standardized biomonitoring sampling protocol during three periods from 1997 to 2015. To understand the patterns along the river continuum, we covered a substantial gradient of source distance (3-260 km). The assemblages previously showed a high increase in total species richness and abundances of many native species. As functional richness directly depends on species richness by virtue of probability, we introduced a novel concept of rarefied functional richness, where assemblages of the species richer period were rarefied to equal the number of species in the less species rich period at each site. We found a significant functional enrichment, predominantly independent of the higher number of species and tending towards a unimodal pattern along the source distance. The functional composition overall shifted to that of downstream sections in all source distance intervals, based mainly on life cycle, body size, locomotion, representation of several feeding groups, and dispersal abilities. The shift was mostly indicative of the substantial effects of lower flow conditions associated with fine sediment deposition, increased temperature and an increase in resources, mainly for collectors/gatherers and predators.

The postglacial recolonisation of temperate forest biota is a key process shaping modern European biodiversity, but its tempo is difficult to reconstruct because most palaeoecological records lack sufficient temporal resolution. This limitation applies to most Western Carpathian palaeomalacological sequences, despite the region being a key refugial source for recolonisation. Here, we document the mid-Holocene assembly of forest mollusc communities at the Valca tufa-wetland site in the Mala Fatra Mts. (Slovakia) using a high-resolution multiproxy record combining molluscs with plant macrofossils, stable isotopes, and geochemistry. Although mixed forest vegetation was already established at the site prior to the studied interval (ca 7800 cal yr BP), forest mollusc communities remained species-poor for several centuries, indicating a pronounced lag between forest development and the build-up of forest specialist fauna. The most abrupt rise in forest mollusc diversity occurred around 7150 cal yr BP, when most strictly forest species appeared within approximately 150 years. This rapid community expansion immediately followed an episodic local habitat disturbance recorded consistently across proxies, whereas independent downscaled climate simulations indicate no significant climatic shift during the same interval. Compared with other Western Carpathian records, Valca thus shows a markedly delayed yet unusually abrupt establishment of forest mollusc communities. We interpret this pattern as evidence that local habitat dynamics, topographic setting, and landscape connectivity can dominate the timing and rate of postglacial community assembly under a broadly stable regional climate. These results highlight the value of finely resolved multiproxy sequences for disentangling local versus regional drivers of postglacial recolonisation.

The genus Pyramidula (Gastropoda: Pupilloidea) has represented one of the most taxonomically puzzling groups of Western Palaearctic micro land snails owing to a high level of morphological conservatism and shell convergence. We reconstructed Pyramidula phylogeny across the entire Western Palaearctic, using both mitochondrial (COI) and nuclear (ITS1 + ITS2) markers, based on 123 individuals from 89 localities. Unlike earlier efforts, we treated each distinct ITS indel area as a separate binary presence/absence variable that could be used as a genetic character state. Quantitative and qualitative shell features were also coded from 355 individuals sourced from genetically verified populations. Bayesian analysis and maximum likelihood both generated trees with nine well-supported species-level clades, with ITS1 + ITS2 tree resolution being notably improved at shallow phylogenetic levels through formal inclusion of indel information. Each of these clades was also found to possess distinct shell morphology and biogeography. Two are described as new species: Pyramidula koshka Hors & aacute;k & Leonov sp. nov. and Pyramidula pygmaea Hors & aacute;k & Kafimola sp. nov. Our results establish the first comprehensive phylogenetic framework for the genus across the Western Palaearctic. We document how indels can affect phylogenetic inference at multiple evolutionary scales and provide practical guidelines for incorporating them into Bayesian inference and maximum likelihood analyses.

Large branchiopods are globally endangered, mainly due to habitat loss. Their effective conservation depends on information about their distribution and habitat requirements. Although detailed historical records exist on the distribution of 19 species in Slovakia, comprehensive recent data have been lacking to date. Therefore, we investigated over 700 pools in Slovakia, which resulted in 808 records of 17 species. We use these data to examine current species distribution, determinants of species richness, and potential shifts in distribution and phenology by comparison with historical records. Local species richness was positively associated with mean annual temperature and the proportion of pastures, and negatively with distance to a river, proportions of grasslands, and artificial surfaces. While we found three eurythermic species at more sites than before, most species declined in the number of sites. We observed a significant shift in species occurrence toward colder parts of the year, possibly due to climate change. Our results suggest that effective conservation of large branchiopods requires protection of their habitats, particularly temporary wetlands on arable land, pastures, and marshes. This study can contribute to the conservation of large branchiopods by providing updated data on their recent distribution and documenting long-term patterns in distribution and habitat occupancy.

The invasive nematode Angiostrongylus cantonensis (rat lungworm) can cause eosinophilic meningitis in humans. Once restricted to Southeast Asia, A. cantonensis nematodes are now widespread across the tropics and have been reported in Europe. Tenerife, in the Canary Islands, and the Mediterranean region are emerging hotspots. We surveyed gastropods, rats, and lizards across Tenerife and detected the parasite in all host groups at 2.4%- 41.6% prevalence. Using species distribution models, we identified precipitation seasonality as the main driver of habitat suitability; tree cover and climatic variability primarily shaped prevalence patterns. Modeling showed suitable habitats in northeastern Tenerife and several western Canary Islands but limited overlap with areas of dense human population. Multivariate environmental similarity surface analysis comparison with another A. cantonensis hotspot, Hawaii, USA, revealed similar environments across the archipelago, except for the novel northeastern Tenerife area. Although no human infections have been reported, continued vigilance is warranted because A. cantonensis nematodes are established in Tenerife.

Pedicularis palustris, a hemiparasitic plant, can act as an ecosystem engineer by suppressing dominant vegetation and facilitating fen restoration. As fen deterioration continues due to human activities and climate change, conservation interest in this species is increasing. In temperate Europe, where P. palustris is endangered and regionally fragmented, concerns are rising over future commercial cultivation and uncontrolled seed transfer. In this study, we used Restriction Site Associated DNA sequencing (RAD-seq) to assess the genetic structure and differentiation of 18 P. palustris populations across four regions in temperate Europe, and to provide guidance for seed sourcing in restoration practice. In the spatial autocorrelation analysis, populations within approximately 30 km showed the highest genetic similarity, followed by a steep decline up to about 50 km, suggesting limited gene flow beyond this range. Weak but significant positive autocorrelation persisted up to about 240 km, indicating regional-scale lineage cohesion. Bayesian clustering and Neighbor-Net analyses supported the existence of distinct regional gene pools, while also revealing the genetic uniqueness of certain populations. At the broadest scale, genetic affinities did not follow geographic distance, as the Alpine populations clustered with those from the Bohemian Massif, whereas the Western Carpathian populations clustered with those from the Baltic region. Our results demonstrate strong genetic differentiation both within and among regions, and suggest that meaningful provenance of P. palustris extends only over several tens of kilometres. For restoration, we recommend prioritising local seed sources whenever possible. Seed transfers from populations within approximately 30 km can be considered, although further experimental work is needed to confirm this threshold. Where local seed sources are unavailable, seed transfer should remain confined within the same phytogeographical region, with strict avoidance of translocation between the Carpathian and Hercynian units. Uncontrolled translocation or the use of commercial seeds of unknown origin should be avoided.

Abstract Shell morphology in terrestrial gastropods is widely assumed to reflect climatic adaptation, yet empirical support for body size-climate relationships remains inconsistent across scales. We investigated how shell morphology is associated with large-scale climatic gradients in nine rock-dwelling Pyramidula species across 228 sites in the Western Palearctic. We hypothesised that climatic conditions linked to high solar radiation and low precipitation are associated primarily with shell traits potentially mediating conductive heat exchange with sun-exposed limestone substrates rather than with overall body size. For 519 adult shells, we analysed shell width, height, width/height ratio and a novel composite shell geometry index ( SGI ) using linear mixed-effects models with species and locality as random factors. Shell width showed the strongest and most consistent climatic associations, decreasing with increasing solar radiation and decreasing precipitation. In contrast, shell height and body volume exhibited weak or no independent climatic relationships. The SGI displayed intermediate but consistent responses, particularly to precipitation of the driest month. An additive model combining solar radiation and low precipitation explained nearly 19% of shell width variation. Responses were directionally consistent across species, suggesting shared morphological responses to similar climatic conditions. Observed patterns indicate that shell geometry, particularly shell width, is more closely associated with climatic gradients related to heat and drought stress than is overall body size.

Global biodiversity is increasingly threatened by widespread anthropogenic impacts, which have accelerated since the First Industrial Revolution. Lowland rivers rank among the most affected ecosystems, having undergone centuries of hydromorphological modifications. The scarcity of historical data hampers precise assessments of biodiversity loss in these rivers since 1950, a critical threshold when anthropogenic pressures led to unprecedented ecological change. We compiled a comprehensive dataset of records of Ephemeroptera, Plecoptera and Trichoptera collected in time series from nine Czech lowland rivers over the past 140 years. Additionally, we integrated environmental data on water quality and hydroclimatic parameters spanning the last 60 years. Both alpha and gamma diversity declined steadily until the 1980s, followed by a partial recovery at the turn of the millennium due to water quality improvements. However, biodiversity recovery has remained limited in recent decades due to persistent pollution, climate change and potential depletion of the regional species pool. Assemblages are undergoing compositional changes driven by species turnover, rendering a return to their mid-20th-century baseline unlikely. Our results further highlight a dramatic loss of biodiversity already in the first half of the 20th century, which has not been offset by the partial recovery of rivers observed after 1990. Immediate actions are necessary to prevent further biodiversity decline and safeguard the ecosystem services of lowland rivers.

The status of the six traditionally recognised European Vallonia taxa is considered based on mtDNA and nDNA sequences from five independently sorting loci in combination with morphometric landmark analyses conducted on genetically confirmed shells. These analyses document that only two species are valid (V. costata and V. pulchella). Oversplitting was aided because easily observed and apparently dichotomous traits-in this case the presence or absence of shell ribs-are shown via DNA sequence analyses to not convey useful taxonomic information: they say no more about species status than does hair, eye or skin colour in humans. This work is a reminder that taxonomists must empirically document those macro-scale features which are and those which are not robust indicators of species-scale taxonomic units prior to the initiation of revision. While impossible to accomplish throughout most of taxonomic history, the great expansion of molecular methods and access to these tools mandates that this empirical step underlie all modern revisionary work.

Some of the most remarkable Neolithic finds encountered in central Europe are wells with a wooden construction. These features provide unusual insights into Neolithic societies, their subsistence strategies and the landscape they inhabited. In the last fifteen years, four Early Neolithic wells out of a total of seven such wells known since the 1970s have been discovered in Czechia. One of them is the well at Ostrov, the wooden construction and sedimentary infill of which have made it possible to study diverse topics by taking a multi-proxy approach using a range of complementary methods. The study presented here compares different periods of the well's existence, examines the carpentry skills of the first farmers, investigates sedimentary processes, reveals details about the use and decline of the well, addresses its location relative to that of the settlement, and reconstructs the environment of the well itself and the surrounding landscape. The water well at Ostrov is a highly unusual find because it probably existed outside of a settlement. The grooved wooden lining used is identical to that of previously investigated wells inside settlements, as are the processes of its use and decline. However, environment-related indicates that the Ostrov well was located in an open landscape with sparse vegetation and was perhaps only used by-passing herdsmen.

While biodiversity loss is undeniably a global phenomenon, an increase in taxonomic richness has recently been reported from some ecosystems and spatial scales. A striking increase in abundance and/or species richness has been documented from temperate rivers over the last 25 years, with many of the expanding species (i.e. winners) being native species. However, the lack of repeatedly collected local environmental data prevents the exploration of their niche dynamics and also makes it difficult to distinguish between possible causes. We fill this gap by using species occurrence data from 65 pristine Czech rivers sampled in 1997-2000 and 2015. The same methods were used for sampling macroinvertebrates and measuring environmental parameters in both periods. We selected 43 winners, defined as taxonomically validated and originally non-rare native macroinvertebrate species whose occupancy increased by at least six sites between the time periods. We searched for consistent patterns of niche dynamics (i.e. stability, expansion and restriction) among species that might contribute most to the overall increase in species richness. Using several biological traits, we also compared the winners with the other 253 taxa collected to look for differences. Analysis of the occurrence data showed that niche stability was by far the predominant pattern of the niche dynamics. This clearly indicates that the winners fill their original niches, with a limited contribution of niche shift or expansion, depending on the species. As no significant differences in either temperature preferences or the other biological traits were found between the winners and the other taxa, there is no unique set of functional traits that explain the success of the winners. The observed mechanism of filling the original niche space by the spreading native species not only explains the increase in local species richness, but also contributes to support the hypothesis of a climate-driven increase in ecosystem energy flow from a new perspective. The increased metabolism of the system may relax interspecific competition allowing it to carry more individuals and species, even without the need for an increase in nutrients and ecosystem recovery.

The glacial/interglacial cycles have shaped the landscape of temperate Europe for the past 2.5 million years, with open landscapes prevailing during the glacial and forested landscapes during the interglacial periods. However, the survival and recolonization strategies of temperate forest species during glacial phases remain poorly understood and hotly debated. This study investigates the persistence and postglacial dispersal of forest molluscs in the Western Carpathians by analysing molluscs from 126 Last Glacial and Early Holocene sites. Radiocarbon dating was applied to directly date shells of the target forest species, minimizing the risk of contamination from colluvial sediments. Our results confirm the presence of 15 forest snails in 33 sites in the region for the last 44 ka, with evidence of five species surviving the MIS 2. These findings support the hypothesis of localized microrefugia in the Western Carpathians, which allowed forest species to persist during unfavourable climatic conditions and facilitated their recolonization in the Holocene. In addition, our study highlights considerable temporal variation in mollusc successional patterns, with a sharp increase in forest species during the post‐Last Glacial Maximum period. Despite these advances, the exact location of glacial (micro)refugia remains unclear for many species, highlighting the need for further research. This study provides new insights into the complex biogeographical history of forest molluscs in temperate Europe, emphasizing the need for high‐resolution dating techniques and extensive sampling to accurately reconstruct past environmental changes.

The remarkable phenotypic plasticity of land snail shells often results in convergent evolution, leading to frequent taxonomic misidentifications and non-monophyletic classifications. The taxonomy of the Holarctic micro land snails related to Euconulus fulvus has been particularly challenging to resolve. This study integrates mitochondrial and nuclear DNA phylogenetics, geometric morphometrics, and climate suitability modeling to clarify the phylogenetic and taxonomic status of an East Asian lineage within this group. We confirm that this lineage represents a distinct and previously misclassified species, Euconulus harimensis, which was formerly placed within the genus Parakaliella. While standard mtDNA and nDNA markers showed this evolutionary lineage as polyphyletic, two newly developed nuclear markers (ZN507 and TEP1) resolved the lineage, except for one individual, within a single robust clade of E. harimensis. Geometric morphometric analyses revealed significant differences in shell shape, which, along with unique shell microsculpture, further support its taxonomic separation. Although E. harimensis possesses the smallest distribution range of all related species, it exhibits the highest intraspecific genetic diversity. The models of suitable climatic conditions for both the present and the Last Glacial Maximum showed no major shifts, suggesting high climatic stability of the species range during the Pleistocene. This, along with other palaeobiogeographic factors, may have contributed to the unexpectedly high intraspecific genetic diversity of this species despite its limited range. Our findings provide new insights into the evolutionary processes that shape land snail inter- and intraspecific diversity, with implications for their taxonomy, which has often relied on shell morphology only. Additionally, phylogenetic analysis based on the new markers sheds novel light on the taxonomy and evolution of E. fulvus and E. alderi, highlighting the need for further taxonomic research.

The Faroe Islands, an isolated North Atlantic archipelago, are characterized by a grassland vegetation, which is shaped by strong winds and, since human settlement, also by intensive sheep grazing. This study, conducted in August 2023, investigated terrestrial gastropod fauna across 46 sites on six islands: Vagár, Streymoy, Eysturoy, Kunoy, Borðoy, and Viðoy. We found 26 gastropod species, including two new species for the archipelago (Euconulus fulvus and Vertigo angustior). Several rare species were found at new locations, including Lauria cylindracea, previously only known from a single site on Suðuoy, now documented at two additional sites on Vagár and Streymoy. Species richness at the sites varied between 1 and 16 species, with an average of five species. The fauna is notably slug-dominated, as on average more slug species were found at a site than snail species. Our results illustrate the effects of overgrazing by sheep, which limits gastropod diversity to refuges such as steep rocky outcrops, tall riparian vegetation in narrow canyons, and less disturbed wetlands. The snail fauna of the Faroes is relatively species-poor (31 species in total) and is dominated by introduced generalists and non-native slugs, while micro-snails, which are common in other insular areas with similar climates, are notably absent.

Angiostrongylus cantonensis is an invasive parasitic nematode and zoonotic pathogen responsible for eosinophilic meningitis. Originally native to Southeast Asia, it is now globally distributed across tropical and subtropical regions and is approaching Europe, with Tenerife as a key hotspot. This study investigates the distribution and prevalence of A. cantonensis in Tenerife across three host groups (rats, gastropods, lizards). Based on prevalence data, we modelled its potential distribution using species distribution models (SDMs) and compared climatic conditions with Hawaii, a region with frequent human cases. Field surveys confirmed A. cantonensis in endemic and introduced gastropods (25.6%; 179/698), rats (21.5%; 14/79), and lizards (24.0%; 31/129), with local prevalence ranging from 2.4% to 41.6%. MaxEnt and Boosted Regression Tree models identified precipitation seasonality as the main driver of distribution, while prevalence was influenced primarily by tree cover density and climatic variability. Northeastern Tenerife, La Gomera, La Palma, and El Hierro showed the highest habitat suitability. However, overlap with densely populated areas was limited, possibly explaining the absence of reported human cases. The MESS analysis, based on climatic data from Hawaii, indicated moderate to high environmental similarity across most of the Canary Islands, except in northeastern Tenerife, where conditions were outside the range observed in Hawaii. A. cantonensis is firmly established in Tenerife, but human cases remain absent, likely due to limited human exposure, cultural practices, and geographic separation of parasite hotspots from urban zones. Our findings highlight the importance of integrating ecological and epidemiological data in zoonotic risk assessments. ### Competing Interest Statement The authors have declared no competing interest.

Cryptic species represent an ever-increasing proportion of discovered biological diversity. Thus, the number of observations of cryptic species co-occurring in syntopy also increases, raising the question of mechanisms facilitating this phenomenon. Gammarus fossarum is a widespread, ecologically important, and diversified cryptic species complex with dozens of deeply divergent lineages of Miocene origin, some of which have been observed in syntopy in its European range. We used a multifaceted approach to study the ecology of two syntopic, genetically differentiated G. fossarum lineages in the stable environment of a calcareous spring fen. We investigated the effects of spatial distribution of sampling sites and local environmental factors (water chemistry, substrate composition) on the fine-scale distribution of the two lineages, together with their trophic ecology (delta 13C, delta 15N and gut content analysis). Moreover, we assessed functional morphological differentiation of the lineages, and compared identification based on mitochondrial DNA with variation at three nuclear markers to confirm their reproductive isolation. Small-scale syntopy of both lineages prevailed across the studied locality, having been observed at 14 out of 15 sampling spots. Lineage ratios varied within the spring fen; they were significantly affected by spatial proximity between the sampling spots, but not by local environmental conditions. The two lineages significantly differed in body size as well as trophic niche. However, they were essentially morphologically indistinguishable, although significant shifts were observed in a few phenotypic traits mainly related to feeding. The lack of nuclear allele sharing confirmed the existence of a strong reproductive barrier between them. The two studied G. fossarum lineages are reproductively isolated species that significantly differ in trophic ecology and body size in syntopy. Their local coexistence may thus be facilitated by trophic niche differentiation due to alternative resource use. Our results add to the growing body of evidence that morphologically cryptic species may not be functionally fully equivalent, indicating that cryptic species complexes may be more ecologically differentiated than currently known.

Iceland is the westernmost stronghold of European flora and fauna in the North Atlantic and provides a model system for studying post-glacial colonisation. We conducted quantitative sampling of terrestrial gastropods at 97 natural sites in Iceland between 2016 and 2024, documenting 29 species. Local diversity ranged from zero to 14 species (10 excluding slugs), with an average of five species (four excluding slugs). Of the species recorded, Carychium tridentatum (Risso, 1826), Euconulus alderi (Gray, 1840), Vertigo lilljeborgi (Westerlund, 1871) and V. substriata (Jeffreys, 1833) are new to Iceland and all occur in minerotrophic fens along the south coast. Their distribution is highly localised, with C. tridentatum and V. lilljeborgi occurring at only one and two sites respectively. Their absence in similar habitats in the north, except for a single record of V. lilljeborgi , suggests a climate-driven limitation. Phylogenetic reconstruction and haplotype networks based on mitochondrial DNA confirm their European origin and are consistent with previously studied species. Genetic similarities between Icelandic populations and those from the British Isles and mainland Europe support the hypothesis of natural dispersal via migratory birds. Our results emphasise the role of climate and habitat heterogeneity in shaping the Icelandic gastropod fauna, while suggesting that most species arrived postglacially through passive dispersal mechanisms. This study expands the knowledge of Icelandic biodiversity and underscores the importance of wetlands as refugia for rare species in this extreme environment.

Biogeographical relicts, particularly glacial relicts, are species that have survived postglacial climatic shifts in isolated refugia. In temperate Europe, such species are commonly found in high-altitude mountain ranges, including the Alps, Carpathians, and Pyrenees. While glacial relict land snails are well-documented in the Alps and Carpathians, their occurrence in the Pyrenees remains largely unexplored. In this study, we report the first records of Columella columella in the Iberian Peninsula, found in alpine rocky tundra and alkaline spring fen habitats, far south of its known distribution. Additionally, we report the first presence of Pyramidula saxatilis in Spain, a rock-dwelling species with a distinct Pyrenean haplotype, suggesting its long-term isolation. Our findings also challenge previous records of Vertigo genesii in the Pyrenees, which seem to represent Vertigo hoppii (syn. V. arctica). Furthermore, we document Vertigo alpestris for the first time in Spain, revealing a unique haplotype shared with an Icelandic population. These findings highlight the Pyrenees as a potential southern refugium for glacial relict snails and emphasize the need for further research and conservation measures to protect these highly isolated populations from habitat degradation, particularly due to overgrazing.

Lowland standing waters in Central Europe are biodiversity hotspots for aquatic molluscs but are increasingly threatened by anthropogenic influences, particularly intensive fish farming. This study investigates the effects of environmental variables, fish farming practices, and pond protection on mollusc diversity across three geographic regions in the Czech Republic. Mollusc assemblages were surveyed in 89 ponds, with environmental variables measured to assess drivers of species richness and community composition. Protected and unprotected ponds were compared to evaluate the role of conservation measures. A total of 38 mollusc species were identified, with the Odra region being the most species-rich. Species richness was positively influenced by littoral organic matter and vegetation cover, while chlorophyll-a concentration had a negative effect. Available data from the Labe region on fish farming showed water transparency as the best proxy of habitat quality, outweighing fish stock and supplementary feed data in explanatory power. Protected ponds supported significantly more diverse assemblages, including rare and sensitive taxa, emphasizing the importance of high-quality littoral zones and reduced anthropogenic disturbance. This study underscores the critical role of littoral habitat quality, trophic state of water, and legal protection in maintaining mollusc biodiversity in lowland ponds.

Coarse woody debris (CWD) plays a crucial role in maintaining biodiversity in forest ecosystems by supporting habitat complexity and influencing soil properties. This study investigates the effects of CWD on gastropod diversity within managed spruce (Picea abies) forests in the Czech Republic, comparing results to nearby nature reserves (NRs). Gastropod species richness and composition were evaluated at both plot (50 m x 50 m) and mesohabitat scales across gradients of CWD and beech (Fagus sylvatica) tree representation. Our results indicate significantly reduced species richness in managed forests (median 7 species per plot) compared to NRs (median 15 species), attributed to lower soil pH, calcium availability, and moisture due to the dominance of spruce and the limited availability of CWD. Species richness was positively influenced by CWD volume, with two amounts identified: a minimum of 4 m3 center dot ha-1 to prevent significant biodiversity loss and 20 m3 center dot ha-1 to support sensitive and dendrophile species. At the within-plot scale, CWD was the species richest mesohabitat, playing a particularly important role in acidic and nutrient-poor environments. Furthermore, beech basal area positively correlated with species richness, mitigating the negative impact of spruce. The findings highlight the critical need for changes in forest management, including increased retention of CWD and integration of deciduous trees, to support biodiversity in intensively managed forests. These measures are particularly urgent given the susceptibility of spruce monocultures to climate change and pest outbreaks. Gastropods, as sessile indicators of environmental change, may serve as effective umbrella species for conservation efforts targeting forest soil biodiversity.