1 Introduction

Snails are a representative of a wide variety of phylums, from aquatic to terrestrial processes, providing rich research materials in terms of evolutionary adaptability and environmental diversity. For example, the genome-wide replication event of the giant African snail is believed to be related to its adaptability in terrestrial ecosystems, which provides clues to understanding the survival of terrestrial snails after the Cretan-Territory extinction event; Africa's biodiversity hotspots showcases the evolutionary patterns of snail species in paleo-climate change, which provides an important background for studying the geographical distribution and genetic structure of species.

Terrestrial snails are not only a key link in the food chain in the ecosystem, but also affect soil structure and plant communities through their biological activities. In evolutionary research, the diversity and distribution patterns of terrestrial snails provide a unique perspective for understanding biogeography and evolutionary mechanisms. Biogeographic models of snails show the diversity of species on a global scale, revealing the role of niche fidelity and long-distance diffusion in species diversity. The fossil record of terrestrial snails provides valuable evidence for understanding their evolutionary history.

This study integrates the systematic geography and fossil records of African terrestrial snails to trace their evolutionary origins and diffusion paths. By analyzing the genetic diversity and distribution patterns of snail populations in different regions, we hope to analyze the key factors affecting the diversity of terrestrial snails. The role of snails in ecosystem and evolutionary research will also be discussed in the article, hoping to provide a comprehensive perspective for the evolutionary research of terrestrial snails in Africa.

2 Species Diversity and Systematic Classification of African Terrestrial Snails

2.1 Major taxa and representative genera

The diversity of terrestrial snails in Africa showed significant differences in different regions. In South Africa, the terrestrial genus Gittenodouardia is the most abundant member of Cerastidae species, which is mainly distributed in highly fragmented shallow African and Indian Ocean coastal (IOCB) forest biomes (Raphalo et al., 2020). Since the early 20th century, research on molluscs in West Africa has attracted widespread attention, mainly focusing on species inhabiting coastal and shallow water habitats. Phyllins are marine benthic cephalospas, with a dorsal flat body shape, widely distributed in seas of all latitudes around the world, living in a soft bottom environment of silt from shallow water to deep seas. A distinctive feature of such snails is that they have a smooth or engraved shell with a round to square shape "disc" and is usually an inner shell with a length of between 1 and 40 mm (Malaquias et al., 2016).

2.2 Evolution and debates in classification systems

The classification system of terrestrial snails in Africa has been evolving, mainly due to the continuous in-depth research on molecular data and morphological. Historically, the classification of terrestrial mollusks in South Africa has relied primarily on shell morphology and the anatomical characteristics of reproductive organs for species identification. However, relying solely on morphological traits may lead to taxonomic confusion and an underestimation of species diversity.. Recent research on mitochondrial DNA systems in terrestrial molluscs in South Africa reveals a large number of new diversity. Combining molecular and morphological data, three and one new species were identified in two genera of the Rhytididae family. Based on molecular data, species complexes were found in three major subgenus of the genus Natalina (Natalina s.s., Afrorhytida and Capitina). These studies suggest that other terrestrial spirons that have not been studied are likely to have similar, yet-documented primary taxonomic diversity (Raphalo et al., 2020). In southern Africa, molecular phylogenetic studies of the genus Natalina show consistency with traditional morphological classifications, supporting the promotion of its subgenus to independent genus. These studies show that molecular data plays an important role in reevaluating and revising traditional classification systems.

2.3 Species diversity and geographic distribution patterns

The species diversity and geographical distribution of terrestrial snails in Africa are affected by a variety of factors. Several researchers, including Annika Boxnick, investigated the landsnail fauna in Nyungwe Forest National Park in southwestern Rwanda. 50 plots with a height of between 1718 m and 2573 m were studied, and a total of 3461 specimens were collected and assigned to 102 spiral species. Regarding the terrestrial snails species, the Nyungwe Forest is the most abundant forest known in Africa. Comparisons with other forests in the northern rift valley of Albertin suggest that the richness of land snail species in the region is significantly associated with distances from Pleistocene forest poor. Nyungwe Forest is located on the chasm of the Congo Nile, where species may exist in different geographical locations, and Nyungwe Forest provides a highly diverse habitat as it spreads across a wide range of altitudes and species richness decreases with altitude. It is also associated with the presence of bare rocks provided (Boxnick et al., 2015). Bellamya is a species rich in freshwater spironium species widely distributed in China and East Africa. Some researchers have sequenced mitochondrial and nuclear DNA for members of the genus in China and used sequences from some other locations in Africa and Asia to study their phylogenetic and genetic diversity distribution. The species have little genetic differentiation, and by contrast, they observed quite deep differences between the East African lakes, with almost every lake having its own unique clades. The results show that strong disagreement does not necessarily depend on the intrinsic characteristics of the species, but is related to the landscape dynamics of the region (Gu et al., 2019; Vijayan et al., 2022).

3 Applications of Phylogeography in Terrestrial Snail Studies

3.1 Common molecular markers and phylogenetic divergence

Plant geography studies of terrestrial snails often utilize mitochondrial DNA markers, Evelyn M Raphalo, Mary L Cole and Savel R Daniels investigate the evolutionary patterns of two forest-inhabited terrestrial snails (Gittenede de Douardia spadicea and Maizania wahlbergi) in the biodiversity hotspots of Maputaland-Pondoland-Albany. Mitochondrial DNA (mtDNA) sequence datasets were used to infer phylogenetic relationships and estimate divergence times within each species, based on cytochrome c oxidase subunit I (COI) and large subunit ribosomal RNA (16S rRNA) markers. In addition, the rapidly developing COI dataset was used to infer intraspecies genetic structures and population differentiation within the two species. Plant geographic consistency factor (PCF) analysis was used to statistically estimate the degree of consistency between two species in places of the two species. From phylogenetic, G.spadicea exhibits two clades that diverge during the PLIO/Pleistocene, while M. Wahlbergi forms a single light-color clade that is shown (Raphalo et al., 2023). Similarly, the genus gittendouardia was analyzed using COI and 16S rRNA, revealing deep genetic structures and supporting the monogenus of the genus (Raphalo et al., 2020).

3.2 Genetic structure and historical isolation events

Plant geography analysis helps to elucidate genetic structures and historical segregation events in spiral populations. For example, the terrestrial snail Cornu aspersum shows a clear plant geographical structure with a unique lineage, indicating historical migration from North Africa to Europe (Guiller and Madec, 2010). Species with small geographic ranges are generally not expected to exhibit high genetic structure; however, some land snail species appear to be an exception. Serockrassa montserratensis is a critically endangered land snail from Catalonia (northeastern Iberian Peninsula), restricted to talus slopes and occurring within a small and fragmented area. Experts sequenced the COI barcode areas of 152 individuals covering the entire range of the species and found that four genetic groups matched their geographical distribution: a central ancestral group, with five regions containing common haplotypes and three groups confined to only one place. Two of these derived groups are geographically and genetically isolated, while the third is not the most differentiated group geographically isolated (Catalá et al., 2021).

3.3 Strengths and limitations of phylogeographic methods in reconstructing distribution history

Plant geography methods provide powerful tools for reconstructing the distribution history of species, but they also have limitations. Comparative plant geography has been shown to be used to study biological responses to past climate change and is strongest when combined with external assumptions from fossil records or geology. However, the rarity of species with sufficient space to explicit fossil evidence limits the application of this approach. "Reconciling paleodistribution models and comparative physics in the Wet Tropics rainforest land snail Gnarosophia bellendenkerensis (Brazier 1875)" mentioned that an alternative method was developed to compare spatial models of predicted species distribution under serialized paleofuels with molecular plant geography, in this case unique to terrestrial snails in the rainforest of North Queensland, Australia. They also compared the phytogether geography of snails with the snails of several endemic vertebrates and used partnership in all of these methods to enhance the biogeographic inference of this rainforest animal. The prediction of spiral mtDNA plant geography with paleoclimatic modeling relative to climate refuges is associated with the location and size through the late Pleistocene, as well as a wide range of patterns of extinction and recolonization. There is a general agreement between the quantitative estimates from the sequence data (using the possibility and merging method) and the quantitative estimates of distribution modeling. Snail plant geography represents a complex of common and trait-pattern patterns in vertebrates, reflecting a finer geographical scale of durability and subdivision in snails. In general, this multifaceted approach combines spatially explicit paleoclimatic models with comparative plant geography, providing a powerful way to locate historical refuges and understand species’ responses to them (Hugall et al., 2002). However, dependence on mitochondrial DNA can sometimes be limited to what is seen in the study of Bellamia snails, where nuclear DNA also needs to fully understand genetic diversity and evolutionary trajectory (Gu et al., 2019).

4 Historical Evolutionary Clues from Fossil Records

4.1 Major fossil discoveries and distribution of african terrestrial snails

The fossil record of terrestrial snails in Africa provides important clues to understanding their evolutionary history. In Tumweze's research team, snail species with different habitats and altitudes in Africa were analyzed, focusing on the environment of alpine or "Sky Island" to explore how current climate and historical geological factors affect the distribution and evolutionary process of species; using fossil-calibrated multigene phylogenetic trees, including two mitochondrial genes (cox1 and 16S) and two nuclear genes (ITS2 and H3), based on fossil-calibrated Bayesian phylogenetic inference, a strong support phylogenetic tree was constructed, and the phylogenetic relationship between the four major snail groups was analyzed. The results show that colonization in high altitude areas only exists in the Bulinus truncatus/tropicus complex. Several independent colonization events occurred in the Pleistocene and Pleistocene, mainly from adjacent areas of various mountain ranges. Most species originate from low to moderate elevations. The ethiopian plateau, Kenya and Lesotho highlands show significant exogenousness (Tumwebaze et al., 2022). Lakes and rivers in East Africa undergo frequent expansion and contraction, and this dynamic change is also reflected in the fossil record, showing the diversification of terrestrial snails in these environments (Gu et al., 2019).

4.2 Fossil types and inferred paleoecological contexts

The diversity of fossil types reflects different paleoecological environments. Viviparidae (commonly known as river snails) is a predominant group of freshwater snails, with an almost global distribution reaching its highest taxonomic and morphological diversity in Southeast Asia. Björn Stelbrink et al. used a comprehensive genetic dataset containing mitochondrial and nuclear markers, including 24 species of 28 genera across the entire family. In order to reconstruct the spatial and temporal evolution in vivo on a global scale, they reconstructed the phylogenetic fossil calibration and found that a common law among different fetal spiral groups is that species living in static environments usually have engraved snail shells, while only one highly engraved species was found in the reflowing environments. Their research shows that this shell carving is closely related to habitat and evolves independently in the snails in water-static environments. High transition rates between shell patterns in water-static environments may lead to significantly different shell morphology coexisting in multiple lakes. In contrast, in flowing environments, we observe a directional evolutionary trend towards smooth shells, which perhaps explains why engraved shells are rarely seen in these environments (Stelbrink et al., 2020). In South Africa, spiral fossils of the genus Gittenodouardia reveal diversification during the Miocene and Late Miocene, during which reduced precipitation and contraction of forest biota may be the drivers of its diversity (Raphalo et al., 2020).

4.3 Morphological and phylogenetic links between fossil and extant species

Fossils provide important insights into our understanding of phylogenetic medical history by using it as calibration points for differential time estimates. However, uncertainty in fossil record may seriously affect the estimated node age due to parallel evolution and convergent evolution. In the article Phylogenomic analyses reveal incongruences between divergence times and fossil records of freshwater snails in East Asia", experts compared and compared the two freshwater genus (cipangopaludina and Margarya) of phylogenetic differences with geological and fossil history. The cipangopaludina species is usually a widely distributed species in East Asia, but the existing species are endemic to ancient lakes in Yunnan, China. According to some previous studies, parallel evolution or convergent evolution of shell morphology has occurred several times in the family, which may affect the estimation of the difference time using fossil records. In this study, they used SNP data derived from the DDRAD-seq locus to study population history for the two genera. Common patterns of lineages diversified from widely distributed lineages in the Miocene, in which an ancient lake occurred in the Pleistocene. The results show that there is a large inconsistency between the estimated time of systemic gene difference, some fossil records, and the age of ancient lakes. These findings suggest that some fossil records may be misidentified in these groups and stress the need for careful evaluation of geological evidence and fossil records when using them for disagreement time estimates (Hirano et al., 2023). Genomic studies of giant African snails show that genome-wide replication events may play an important role in their adaptation to terrestrial ecosystems, a discovery that provides a new perspective on the evolutionary link between fossils and existing species (Liu et al., 2020)..

5 Influence of African Geological History on Snail Evolution

5.1 Plate tectonics and paleogeographic changes

Plate tectonics and paleogeographic changes in Africa have had a profound impact on the evolution of terrestrial snails. Taking a tropical freshwater genus in Africa as the research object, experts discussed its geographical origin and phylogenetic relationship to evaluate the role of river system evolution in species diversity and distribution range evolution. Based on sampling covering the entire geographical distribution range of the genus, a fossil calibration-based polygenic molecular phylogenetic tree was constructed, and the maximum likelihood method and Bayesian inference were used for analysis. After applying the species demarcation method, the researchers estimated the ancestral geographic regions and habitats and analyzed the changes in species diversity rates through the ‘lineage-time map’. The genus Lanistes is likely to originate from the Eocene (about 50 million years ago), and its 23 existing operating taxa (OTUs) are likely to be distributed in Central Africa and the adjacent Lower Guinea biogeographical areas. The study also found that around the Miocene, the accumulation rate of species suddenly increased and then gradually decreased to the present. Biogeographic analysis further showed that Madagascar spread from East Africa, and the Zambezi River Basin experienced at least two independent colonization events. Seven species in this genus are distributed only in rivers, and three species live only in lakes. Estimates of ancestral habitats suggest that the initial ancestors of the genus Lanistes are likely to originate from river environments (Mahulu et al., 2021).

5.2 Paleoclimatic changes and habitat dynamics

Paleoclimatic change has a significant impact on the evolution and distribution of African snails. The tropical Asian freshwater snail - Indoplanorbis exustus, studies on its molecular data show that I. exustus is actually a species complex composed of multiple candidate species. The major species diversification occurs in the plains of northern India or in northeastern India. These species formation events are mainly heterogeneous species formation driven by a series of drought events from the late Miocene to the early Pleistocene. All species did not exhibit the genetic structure corresponding to a high diffusion capacity, and during the Pleistocene, all species experienced population fluctuations, possibly affected by Quaternary climate fluctuations (Sil et al., 2022). In East Africa, frequent expansion and retreat of lakes and rivers are closely related to climate change, and this dynamic environment promotes genetic diversity and population differentiation of snails (Gu et al., 2019). In addition, climate change has also affected habitat dynamics of snails, leading to regional differences in species diversity (Raphalo et al., 2023).

5.3 Geographic barriers: mountains, deserts, and river systems

Geographical barriers in Africa such as mountain ranges, deserts and river systems have had an important impact on the evolutionary path of land snails. Terrestrial snails are native to the Mediterranean region and have become the subject of multiple anatomical and molecular biology research. The study found that it can be divided into two lineages within the distribution range of North Africa, named ‘Eastern’ and ‘Western’ respectively. The original biogeographic hypothesis believed that paleogeographic events of the Oligocene and shelters of the Quaternary Ice Age jointly shaped the spatial pattern of its genetic variation. The research results show that the two previously described genealogy of "East/West" no longer represents clear biogeographic entities. Phylogenetic analysis revealed the existence of seven lineages, did not support the Tyrrhenian vicariance hypothesis (Tyrrhenian Sea) and showed that C. a. aspersum is likely to originate in North Africa. New biogeographic models suggest that the species initially spread from North Africa to areas around the Iberian Peninsula and the Tyrrhenian Sea, and the diffusion pathway could be achieved through land bridge connections during the Messinian Salinity Crisis and the channels formed during the Pleistocene Glacier. In addition, historical events not only affect the genetic structure, but also have an impact on the morphological variation pattern; while recent diffusion events have promoted secondary contact between different lineages. In the Southern Mediterranean, multiple lineages are still confined to their initial distribution areas; while widespread lineages may rapidly redisperse throughout the Mediterranean during the Holocene due to stronger adaptability and human transmission activities (Sherpa et al., 2018). The evolution of river systems also has an impact on the diversification of snails, especially in freshwater snails, where changes in flow direction of rivers and dynamic changes in lakes promote population differentiation and diversification (Figure 1) (Mahulu et al., 2021).

6 Dispersal Mechanisms and Migration Pathways of African Terrestrial Snails

6.1 Hypotheses and evidence for centers of origin

The evolutionary origins of African terrestrial snails are relatively complex and are affected by multiple factors of biogeographic history and ecological environment. The Gittenodouardia genus is widely distributed in forest biomes along South Africa and the Indian Ocean coast, showing dependence on humid and stable forest environments. This distribution pattern suggests that the coastal areas of South Africa and its adjacent areas may be one of the centers of origin of the genus. Relevant molecular phylogenetic studies have shown that such genera has shown significant lineage differentiation during periods of intense climatic oscillations in the Pliocene (Raphalo et al., 2020). Habitat isolation and reconnection brought about by climate change provide opportunities for lineage differentiation and species formation, thereby driving the evolution of its diversity. The terrestrial spiral Cornu aspersum, widely distributed in the Mediterranean region, also provides important clues for studying the origin and diffusion path of terrestrial spirals. Genetic and phytogether evidence shows that the species originated in North Africa and gradually expanded to southern Europe through the combined effects of natural expansion and human activities in the late Pleistocene, and eventually spread throughout Europe (Guiller and Madec, 2010). Mitochondrial DNA analysis of populations revealed a distinct North-South differentiation structure, with the genetic diversity of North African populations significantly higher than that of European populations, further supporting the idea that North Africa is the center of its origin.

6.2 Ecological niche evolution and geographic variation in dispersal capacity

Ecological niche evolution plays an important role in the diffusion capacity of terrestrial snails. The Vertigo genus shows that species diversity accumulates in a linear manner, with a slight increase in the period 35~30 million years and 25~20 million years, which coincides with the emergence of most subgenus and the climate cooling events in the Northern Hemisphere, respectively. Biogeographic models show that most species differentiation events occur in co-regional environments, that is, there is no change in distribution range, but a few "founder events" promote global diversity. Soil moisture conditions are one of the main variables that define the Vertigo niche, showing significant signals in phylogenetics, but the changes between subgenus are smaller than those within subgenus. On the macroevolutionary scale, changes in geographical distribution range are significantly correlated with changes (or lack of changes) in humidity niches, with most niche changes occurring in co-regional differentiation, while there are almost no niche changes in species formation driven by the founder event. Research shows that under co-regional conditions, Vertigo species occasionally undergo lineage differentiation or achieve individual evolutionary diffusion through adaptation to soil moisture niches; but long-distance diffusion is more likely to be successful without niche changes. Vertigo’s macroevolutionary success is the result of the combined action of neutral mechanisms (such as founder effects and genetic drift) and selective mechanisms (such as adaptive habitat changes) (Horsák et al., 2024).

6.3 Key corridors and dispersal barriers: climate zones and topographical features

Climate regions and topographic characteristics can be said to be obstacles to the spread of terrestrial snails in Africa. Related plant geography shows that during the Miocene/Pliocene, the contraction of forest biomes caused by reduced precipitation, resulting in deep genetic structures and diversification within the genus (Raphalo et al., 2020). Researchers conducted a systematic survey on terrestrial snails belonging to the Caucasotachea atrolabiata complex in the Caucasus region. Currently, the complex is divided into three species: C. atrolabiata in the northwestern Caucasus, C. calligera in the Transcaucasus, and C. intercedens in the eastern Pontes Mountain. Phylogenetic analysis based on AFLP data and hybridization analysis showed that the complex was actually composed of two population clusters. The mitochondrial haplotype of C. a. atrolabiata in Türkiye can only be explained by passive diffusion across the Black Sea. C. a. The distribution pattern of atrolabiata and the separation distribution phenomenon of other terrestrial snails on both sides of the Black Sea are not due to common causes, but are the result of long-distance diffusion events occurring at different times (Neiber et al., 2016).

7 Integrative Analyses of Phylogeographic and Fossil Data

7.1 Molecular clocks and fossil-calibrated time reconstructions

Integrating plant geography and fossil data provides a comprehensive understanding of the evolutionary history and diffusion pathways of terrestrial snails in Africa. This approach combines genetic data with fossil records to reconstruct historical biogeography and diversification patterns of these species. For example, among a few species widely sampled in North Africa to study historical processes that affect current distribution patterns, the terrestrial mollusc Cornu aspersum (=syn. Helix aspersa) provides an excellent biological model for understanding the systematic geographical pattern of North Africa and the surrounding areas of the Western Mediterranean, which helps evaluate the relevant hypotheses that lead to population differentiation. Originally named Helix aspersa Müller, 1774, the terrestrial spiron originated in the Mediterranean country and contains a series of morphotypes and subspecies endemic to North Africa that were originally described in the early 20th century based on shell characteristics. The most common of these is C. a. aspersum, which has become very common in all habitats disturbed by humans, especially in areas with Mediterranean climate, temperate and even subtropical climates. To reconstruct the biogeographic history of this invasive morphology in the Western Mediterranean, researchers have evaluated their spatial variation patterns in shell, genitalia and molecular characteristics by investigating more than 100 populations representing the distribution range of aspersums, including the Western Mediterranean and European coastlines (Guiller and Madec, 2010). Similarly, the phytogeography of Bellamya snails in China and East Africa illustrates how climate and geological history have shaped their evolutionary trajectories, highlighting the role of landscape dynamics in species diversification (Gu et al., 2019).

7.2 Ancestral area reconstruction: joint models and case studies

Molecular clocks calibrated with fossil data are important for estimating the difference times and understanding the evolutionary timeline of the spiral. Some experts’ research on African terrestrial snails uses genome-wide repetition events to estimate species and adaptation timing, assembled the chromosomal-level reference genome of the global invasive species Achatina immaculata, and compared it with another African terrestrial snail Achatina fulica and other published molluscs. Through macro-collinear analysis, collinear blocks, synonymous permutation rate (Ks) peaks, and distribution of Hox gene clusters, they jointly discovered that these two spirals experienced a genome-wide replication event. The event occurred approximately 70 million years ago, close to the species differentiation period of the Sigmurethra-Orthurethra taxa in the order Stylommatophora and the Cretaceous-Territory (K-T) mass extinction event. The concurrence of this time point suggests that WGD may be an event experienced by all Sigmurethra-Orthurethra taxa and may confer ecological adaptation to these species after K-T extinction (Liu et al., 2020).

7.3 Challenges and future directions in multisource data integration

Integrating multiple data sources such as genetic, fossil and ecological data presents challenges, including data compatibility and model complexity. However, it also provides a more powerful opportunity for botanical inference. As demonstrated by the study of giant tree frogs, the integration of environmental modeling and genetic data highlights the potential to achieve synthesis among different data types, thereby increasing confidence in plant geographical conclusions (Carstens and Moshier, 2022). Future research should focus on improving data integration techniques and exploring new ways to overcome these challenges, ultimately enhancing our understanding of the evolutionary history and dispersion pathways of terrestrial snails in Africa.

8 Conclusions and Perspectives

8.1 Major findings in the evolution and dispersal of african terrestrial snails

The evolution and diffusion paths of terrestrial snails in Africa reveal diverse biogeographic processes and ecological adaptation mechanisms. Research shows that the genome-wide replication event of giant African snails may have promoted the improvement of its ecological adaptability following the Cretaceous-Territory extinction event, an event that may be a common feature of all Sigmurethra-Orthurethra species (Liu et al., 2020). The study found that the evolutionary history of terrestrial snails in Africa was closely related to climate change, such as the lineage differentiation of the Gittenedouardia genus in South Africa was associated with climate fluctuations in the Miocene and Pliocenes (Raphalo et al., 2020). In the Mediterranean region, the distribution pattern of Cornu aspersum snails shows a trend of diffusion from North Africa to Europe, reflecting the influence of paleoclimatic and geological events on their diffusion (Guiller and Madec, 2010).

8.2 Current knowledge gaps and methodological bottlenecks

Despite some progress in the evolution and diffusion study of terrestrial snails in Africa, significant knowledge gaps and methodological challenges remain. Incompleteness and possible misidentification of fossil record create uncertainty in the time estimate of divergence (Hirano et al., 2023). Second, the lineage relationships and species diversity of many spiron genera have not been adequately studied, for example, the undescribed diversity of Gittenedouardia genera requires further classification revisions (Raphalo et al., 2020). The existing molecular and morphological data are inconsistent in some cases, limiting a comprehensive understanding of the evolutionary history of certain genera.

8.3 Interdisciplinary integration and implications for conservation biology

Interdisciplinary integration plays a key role in understanding the evolution and spread of terrestrial snails in Africa. By combining molecular data, fossil records and ecological models, researchers are able to reconstruct the evolutionary history and diffusion paths of spirals more accurately (Carstens and Moshier, 2022). This integration not only helps to reveal the biogeographic patterns of terrestrial snails, but also provides important insights into conservation biology. For example, understanding the ecological adaptation and diffusion mechanisms of snails can help develop more effective conservation strategies to address future climate change and the impact of human activities on snail habitats (Horsák et al., 2024).

Acknowledgements

The authors are very grateful to Wang May for reading and also to thank the two peer reviewers for their suggestions.

Conflict of Interest Disclosure

The authors confirm that the study was conducted without any commercial or financial relationships and could be interpreted as a potential conflict of interest.

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