Richness Hotspots Research Articles

Flora and geographic pattern of mountain forests at community level in Taihang Mountains: Results based on plant community survey

Taihang Mountains is located on the eastern edge of the second step of Chinese topography, which is the natural boundary between Loess Plateau and North China Plain and is considered as one of the important priority areas for biodiversity conservation in China. We took 108 counties involved in the generalized Taihang Mountains as the research area to systematically analyze the characteristics of family and genus characters, floristic composition, geographical pattern of plant diversity and species richness hotspots at community level of mountain forests in Taihang Mountains. A total of 963 species of seed plants belonging to 447 genera and 100 families were recorded in 778 forest plots in Taihang Mountains. Within all the species, 12 species of gymnosperms belonging to 7 genera of 3 families, 951 species of angiosperms belonging to 440 genera of 97 families. Herbaceous plants (71.1%) was the dominant life form. The distribution types of families were mainly tropical (38%) and temperate (24%), and the distribution types of genera were mainly temperate (68.7%). The horizontal distribution pattern of plant diversity showed a trend of increasing from southwest to northeast. Species richness was positively correlated with the latitude and longitude. However, the richness patterns of different life-form plants were different, in that herbaceous richness was positively correlated with the longitude and latitude but that of woody plants was not. In the vertical gradient, plant richness of Taihang Mountains presented a single-peak distribution, which was concentrated in the low and middle elevations of 400-1800 m and peaked at 1000-1200 m. Based on the community inventory data, we mapped plant richness of Taihang Mountain forest community. The mountain areas such as Xiaowutai Mountain, Yuntai Mountain, Taiyue Mountain, Wangwu Mountain and Zhongtiao Mountain were identified as hotspots of plant richness, which should be included in the key planning and management areas of the Taihang Mountains priority protection.

Endemicity and community composition of marine species along the NW Pacific and the adjacent Arctic Ocean

The NW Pacific lies in the most productive, rich, and diverse region of the World Ocean. The NW Pacific includes several shallow-water oceanic islands and deep-sea basins differing in depths, hydrology and isolation. The adjacent Arctic Ocean includes the northern Bering and southern Chukchi Sea, areas of high productivity characterized by short food chains and shallow depths. Despite the NW Pacifićs high species richness, characterization of species diversity and species composition in this region remains poorly explored and/or unknown. Here we attempt to discover how geographic boundaries and depth shape current community assemblages in this area by limiting species richness and geographic distribution ranges. All geographic distribution records were extracted from Ocean Biogeographic Information System (OBIS) and Global Biodiversity Information Facility (GBIF). Distribution data were then cleaned, resulting in a final dataset including 324,916 distribution records of 17,414 species ranging from 0 to 10,900 m depth. We calculated the rate of endemicity and alpha species richness per ecoregion. We also showed how species composition and community structure varies between the tropical and temperate NW Pacific and adjacent Arctic Ocean when sampling bias is accounted for using rarefaction. After accounting for sampling bias, the Eastern Philippines had the greatest species richness (for both pelagic and benthic species) in the NW Pacific and its adjacent Arctic Ocean, and the lowest species richness was observed in Papua. Despite the high species richness in the Eastern Philippines, the Yellow Sea and Gulf of Tonkin had the highest benthic species endemicity rates (ca. 70%) and Aleutian Islands had the highest pelagic endemicity rate (ca. 45%) among all other ecoregions. In the NW Pacific, Chordata, Arthropoda, and Mollusca contributed more than 50% to the species composition of the community. In the Arctic Ocean, Arthropoda, Annelida, and Mollusca were the dominant taxa comprising ca. 82% of the species community. Two significantly distinguished clusters (North and South clusters) were identified based on species similarity analysis including ecoregions of the (1) polar Arctic Ocean and temperate North NW Pacific, and (2) tropical and sub-tropical NW Pacific. We also calculated marine species richness hotspots (actual and expected ES50) and centers of endemism in the NW Pacific and adjacent Arctic Ocean. These analyses reveal an opportunity for marine conservation planning effort as reporting species richness and endemicity hotspots could be highly effective in pinpointing and preventing biodiversity loss.

Humboldt's enigma: What causes global patterns of mountain biodiversity?

Mountains contribute disproportionately to the terrestrial biodiversity of Earth, especially in the tropics, where they host hotspots of extraordinary and puzzling richness. With about 25% of all land area, mountain regions are home to more than 85% of the world's species of amphibians, birds, and mammals, many entirely restricted to mountains. Biodiversity varies markedly among these regions. Together with the extreme species richness of some tropical mountains, this variation has proven challenging to explain under traditional climatic hypotheses. However, the complex climatic characteristics of rugged mountain regions differ fundamentally from those of lowland regions, likely playing a key role in generating and maintaining diversity. With ongoing global changes in climate and land use, the role of mountains as refugia for biodiversity may well come under threat.

Weaknesses in the Law Protecting the United Kingdom\u2019s Remarkable Underwater Cultural Heritage: The Need for Modernisation and Reform

Despite the United Kingdom (UK) having been regarded as one of the richest hotspots for underwater cultural heritage (UCH), its policy and practice regarding its protection has displayed some areas of weakness. This paper makes a case to review the legal framework and its overall administration in the UK, in order to protect and preserve any remaining UCH before it is further lost or damaged. First, we introduce some of the flaws in the UK’s legal system protecting UCH, demonstrating how it has led to a considerable loss of cultural heritage and underlining how it is in need of modernisation. This includes discussion of issues raised in a number of recent cases, including the proposed Victory (1744) recovery project, the proposed Goodwin Sands dredging licence and various cases relating to the illegal recovery of material. We then map out how policy is implemented in practice and the role played by various institutions involved with its administration, where we find a schism between what policy intends and what it is achieving in practice. This takes us towards a broader discussion on how legislative reform might look, including a more proactive and ambitious approach to the future management and enjoyment of the UK’s impressive UCH. Here we argue the need for better engagement at the global and regional negotiating table, as well as in favour of adopting a unified and consistent policy which aims to be more sustainable, precautionary, proportionate and inclusive.

Are protected areas preserving ecosystem services and biodiversity? Insights from Mediterranean forests and shrublands

Protected areas (PAs) are essential for biodiversity conservation and the provision of ecosystem services (ES), representing 15% of the earth’s surface and targeted to increase until 17% by 2020. But previous studies showed different results on the effectiveness of PAs in preserving ES and biodiversity, which has implications for landscape conservation. (1) To know whether the spatial distribution of ES (carbon stocks and water provision), biodiversity (woody and bird richness) and conservation variables (threatened bird richness, habitats and geology) varies between PAs (with different protection status) and buffer zones; and (2) to quantify and compare the percentage of high values (hotspots) of ES, biodiversity and conservation variables inside PAs (with different protection status) and buffer zones. We analyzed 108 PAs from a Mediterranean region using linear mixed models with ES, biodiversity and conservation variables as response factors, and type of zone (PA vs buffer) and protection status as fixed factors. We found higher values of carbon stocks in PAs than in buffer zones. We also found more coverage of community-interest habitats, priority-habitats and geological-interest sites in PAs than in buffer zones. However, PAs with higher degree of protection did not provide higher levels of ecosystem services and biodiversity, or vice versa. We found more hotspots of woody richness, bird richness and threatened bird richness in buffer zones than in PAs. This study highlights the importance of landscape planning in conservation, which should include PAs within broader landscapes by considering also their buffer zones and non-PAs. It also emphasizes the importance of integrating ES and biodiversity to define effective conservation policies.

The global biogeography of lizard functional groups

AbstractAimUnderstanding the mechanisms determining species richness is a primary goal of biogeography. Richness patterns of sub‐groups within a taxon are usually assumed to be driven by similar processes. However, if richness of distinct ecological strategies respond differently to the same processes, inferences made for an entire taxon may be misleading. We deconstruct the global lizard assemblage into functional groups and examine the congruence among richness patterns between them. We further examine the species richness – functional richness relationship to elucidate the way functional diversity contributes to the overall species richness patterns.LocationGlobal.MethodsUsing comprehensive biological trait databases we classified the global lizard assemblage into ecological strategies based on body size, diet, activity times and microhabitat preferences, using Archetypal Analysis. We then examined spatial gradients in the richness of each strategy at the one‐degree grid cell, biome, and realm scales.ResultsWe found that lizards can best be characterized by seven “ecological strategies”: scansorial, terrestrial, nocturnal, herbivorous, fossorial, large, and semi‐aquatic. There are large differences among the global richness patterns of these strategies. While the major richness hotspot for lizards in general is in Australia, several strategies exhibit highest richness in the Amazon Basin. Importantly, the global maximum in lizard species richness is achieved at intermediate values of functional diversity and increasing functional diversity further result in a slow decline of species richness.Main conclusionsThe deconstruction of the global lizard assemblage along multiple ecological axes offers a new way to conceive lizard diversity patterns. It suggests that local lizard richness mostly increases when species belonging to particular ecological strategies become hyper‐diverse there, and not because more ecological types are present in the most species rich localities. Thus maximum richness and maximum ecological diversity do not overlap. These results shed light on the global richness pattern of lizards, and highlight previously unidentified spatial patterns in understudied functional groups.

Russula swatica: A new species of Russula based on molecular, light microscopy, and scanning electron microscopy analyses from Swat Valley of Khyber Pakhtunkhwa province of Pakistan.

Himalayan range of Pakistan is one of the diversity rich hotspots of the world. Many areas are yet to be explored here to discover new species of organisms including fungi. During present research, Swat District of Pakistan was explored for fungal diversity. One new species of mushroom Russula swatica (Russulales) is described from Himalayan range of Pakistan and analyzed by light microscopy and scanning electron microscopy as well as by molecular markers. A comprehensive description, photographs, and comparisons with morphologically similar and phylogenetically related species are provided. Conclusions of its phylogenetic relationships within the genus are provided based on the sequence of the nuclear internal transcribed spacer region.

Alpha diversity of vascular plants in European forests

AbstractAimThe former continental‐scale studies modelled coarse‐grained plant species‐richness patterns (gamma diversity). Here we aim to refine this information for European forests by (a) modelling the number of vascular plant species that co‐occur in local communities (alpha diversity) within spatial units of 400 m2; and (b) assessing the factors likely determining the observed spatial patterns in alpha diversity.LocationEurope roughly within 12°W–30°E and 35–60°N.TaxonVascular plants.MethodsThe numbers of co‐occurring vascular plant species were counted in 73,134 georeferenced vegetation plots. Each plot was classified by an expert system into deciduous broadleaf, coniferous or sclerophyllous forest. Random Forest models were used to map and explain spatial patterns in alpha diversity for each forest type separately using 19 environmental, land‐use and historical variables.ResultsOur models explained from 51.0% to 70.9% of the variation in forest alpha diversity. The modelled alpha‐diversity pattern was dominated by a marked gradient from species‐poor north‐western to species‐rich south‐eastern Europe. The most prominent richness hotspots were identified in the Calcareous Alps and adjacent north‐western Dinarides, the Carpathian foothills in Romania and the Western Carpathians in Slovakia. Energy‐related factors, bedrock types and terrain ruggedness were identified as the main variables underlying the observed richness patterns. Alpha diversity increases especially with temperature seasonality in deciduous broadleaf forests, on limestone bedrock in coniferous forests and in areas with low annual actual evapotranspiration in sclerophyllous forests.Main conclusionsWe provide the first predictive maps and analyses of environmental factors driving the alpha diversity of vascular plants across European forests. Such information is important for the general understanding of European biodiversity. This study also demonstrates a high potential of vegetation‐plot databases as sources for robust estimation of the number of vascular plant species that co‐occur at fine spatial grains across large areas.

Spatial Patterns and Determinants of the Diversity of Hemipteran Insects in the Qinghai-Tibetan Plateau

Large-scale patterns of species richness is an important issue in biogeography and ecology. The Qinghai-Tibetan Plateau (QTP) is a biodiversity hotspot in the world, which has an important status in the zoogeographical realms. Here, we analyzed the diversity patterns of Hemipteran insects in the QTP, and tested whether the patterns can be jointly explained by modern environmental as well as historical factors. A comprehensive geographic distribution dataset consisting of 1166 Hemipteran species, which belong to 510 genera and 53 families, was compiled and used in our analyses. Patterns of richness were mapped into a grid-based map with a spatial resolution of 0.5°x 0.5°. An unbalanced diversity pattern of the Hemipteran insects in the QTP was presented, with more species in the eastern and southern parts of the plateau, while few species in the northern and main surface of the plateau. The northwestern Sichuan, the southern Gansu, the southeastern Tibet, the northwestern Yunnan and the eastern Qinghai were identified as diversity hotspots of species richness. Further analyses based on General linear models and Random Forest indicated that the diversity patterns of Hemipteran insects were influenced by both contemporary environmental factors and historical factors (e.g. habitat heterogeneity, climate stability, energy availability). Specifically, the species richness patterns of all Hemipteran insects in the QTP have been mainly affected by elevation range, temperature annual range, min temperature of coldest month, mean temperature of coldest quarter and the temperature change since the Last Glacial Maximum. In contrast, the water-related variables have relatively small effects on species richness. In addition, although habitat heterogeneity was indicated the most important factor for different suborders of Hemiptera, the climate stability was another dominate factor for Heteroptera and Auchenorrhyncha, while Sternorrhyncha was more affected by historical climate change.

An integrative assessment of the diversity, phylogeny, distribution, and conservation of the terrestrial reptiles (Sauropsida, Squamata) of the United Arab Emirates.

In the present study we use an unprecedented database of 5,535 distributional records to infer the diversity, ecological preferences and spatial distribution of the 60 species of terrestrial reptiles of the United Arab Emirates (UAE), and use the 57 native species to test the effectiveness of the protected areas’ network in conserving this unique vertebrate fauna. We infer a time-calibrated phylogeny with 146 species of squamates and 15 genes including all UAE terrestrial reptile species to determine the phylogenetic diversity (PD) and evolutionary distinctiveness (ED) of the native species and to compare it with the distribution of the hotspots of native species richness. The results of this study indicate that the sampling effort is remarkable, covering 75% of the country’s territory representing nearly the entire climatic space of the UAE defined by the mean annual temperature and the total annual precipitation, as well as the multivariate climatic space defined by a principal component analysis (PCA). Species richness is highest in the northeast of the country, in a transitional area from sandy desert to the mountainous terrain of the Hajar Mountains. The highest PD of a single square cell of 10 arc-minutes grid is of 2,430 million years (my) of accumulated evolutionary history and the strong correlation between PD and species richness suggests that the raw number of species is a good surrogate to quantify the evolutionary history (i.e., PD). The species with the highest values of ED are those in families represented by only one species in the UAE. Finally, the assessment of the UAE protected areas shows that, despite their relevance in protecting the terrestrial reptiles, they do not offer adequate protection for some threatened species. Therefore, a reassessment of some of the protected areas or the creation of species specific conservation action plans are recommended in order to ensure the preservation of the unique diversity of UAE terrestrial reptiles.

Hotspots of human impact on threatened terrestrial vertebrates.

Conserving threatened species requires identifying where across their range they are being impacted by threats, yet this remains unresolved across most of Earth. Here, we present a global analysis of cumulative human impacts on threatened species by using a spatial framework that jointly considers the co-occurrence of eight threatening processes and the distribution of 5,457 terrestrial vertebrates. We show that impacts to species are widespread, occurring across 84% of Earth’s surface, and identify hotspots of impacted species richness and coolspots of unimpacted species richness. Almost one-quarter of assessed species are impacted across >90% of their distribution, and approximately 7% are impacted across their entire range. These results foreshadow localised extirpations and potential extinctions without conservation action. The spatial framework developed here offers a tool for defining strategies to directly mitigate the threats driving species’ declines, providing essential information for future national and global conservation agendas.

Predicting hotspots for threatened plant species in boreal peatlands

Understanding the spatial patterns of species distribution and predicting suitable habitats for threatened species are central themes in land use management and planning. In this study, we examined the geographic distribution of threatened mire plant species and identified their national hotspots, i.e. areas with high amounts of suitable habitats for threatened mire plant species. We also determined the main environmental correlates related to the distribution patterns of these species. The specific aims were to: (1) identify the environmental variables that control the distribution of threatened peatland species in a boreal aapa mire zone, Finland; and (2) to identify the richness patterns and hotspots of threatened species. Our results showed that the combination of individual species models offers a useful tool for identifying landscape-scale richness patterns for threatened plant species. The modeling performance was high across the modelled species, and the richness patterns generated by single models coincide with the expected richness pattern based on expert knowledge. The method is therefore a powerful tool for basic biodiversity applications. In cases where reliable models for species occurrences and hotspots can be produced, these models can play a significant role in land-use planning and help managers to meet different conservation challenges.

Mapping wader biodiversity along the East Asian—Australasian flyway

Background and goalThe study is conducted to facilitate conservation of migratory wader species along the East Asian-Australasian Flyway, particularly to 1) Identify hotspots of wader species richness along the flyway and effectively map how these might change between breeding, non-breeding and migratory phases; 2) Determine if the existing network of protected areas (PA) is sufficient to effectively conserve wader biodiversity hotspots along the EAAF; 3) Assess how species distribution models can provide complementary distribution estimates to existing BirdLife range maps.MethodsWe use a species distribution modelling (SDM) approach (MaxEnt) to develop temporally explicit individual range maps of 57 migratory wader species across their annual cycle, including breeding, non-breeding and migratory phases, which in turn provide the first biodiversity hotspot map of migratory waders along the EAAF for each of these phases. We assess the protected area coverage during each migration period, and analyse the dominant environmental drivers of distributions for each period. Additionally, we compare model hotspots to those existing range maps of the same species obtained from the BirdLife Internationals’ database.ResultsOur model results indicate an overall higher and a spatially different species richness pattern compared to that derived from a wader biodiversity hotspot map based on BirdLife range maps. Field observation records from the eBird database for our 57 study species confirm many of the hotspots revealed by model outputs (especially within the Yellow Sea coastal region), suggesting that current richness of the EAAF may have been underestimated and certain hotspots overlooked. Less than 10% of the terrestrial zones area (inland and coastal) which support waders are protected and, only 5% of areas with the highest 10% species richness is protected.Main conclusionsThe study results suggest the need for new areas for migratory wader research and conservation priorities including Yellow Sea region and Russian far-East. It also suggests a need to increase the coverage and percentage of current PA network to achieve Aichi Target 11 for Flyway countries, including giving stronger consideration to the temporal dynamics of wader migration.

The strategy for protecting threatened forest species richness in the northeastern China from the effects of climate change

Climate change has the potential to severely threaten the plant species in the forests of northeastern China. The field surveys performed for this study spanned 4 years and identified the endangered species present in the forests of northeastern China. We conducted a detailed investigation of 2,884 study plots and selected 29 nationally protected plant species (sample sizes ≥ 5), namely, threatened species for further analysis. We modelled and mapped the potential distributions of these 29 threatened species, and found that threatened species richness hotspots are currently distributed in the eastern and northeastern areas of the studied region and will move geographically. This study focused on the strategy for protecting threatened forest species richness by analysing the change trend of species richness and planning of priority protection areas due to climate change.

The strategy for protecting threatened forest species richness in northeastern China from the effects of climate change

Climate change has the potential to severely threaten the plant species in the forests of northeastern China. The field surveys performed for this study spanned 4 years and identified the endangered species present in the forests of northeastern China. We conducted a detailed investigation of 2,884 study plots and selected 29 nationally protected plant species (sample sizes ≥ 5), namely, threatened species for further analysis. We modelled and mapped the potential distributions of these 29 threatened species, and found that threatened species richness hotspots are currently distributed in the eastern and northeastern areas of the studied region and will move geographically. This study focused on the strategy for protecting threatened forest species richness by analysing the change trend of species richness and planning of priority protection areas due to climate change.

Application of Self-Assembled Raman Spectrum-Enhanced Substrate in Detection of Dissolved Furfural in Insulating Oil.

Accurate detection of dissolved aging features in transformer oil is the key to judging the aging degree of oil-paper insulation. In this work, in order to realize in situ detection of furfural dissolved in transformer oil, silver nanoparticles were self-assembled on the surface of gold film with P-aminophenylthiophenol (PATP) as a coupling agent. Rhodamine-6G (R6G) was used as the probe molecule to test the enhancement effect. By optimizing the molecular concentration, molecular deposition time, and silver sol deposition time of PATP, the nanoparticles were made more uniform and compact, and an enhanced substrate with rich hot spots was obtained. The optimum substrate was developed, and surface-enhanced Raman spectroscopy (SERS) detection of trace furfural dissolved in transformer oil was realized. The results showed that the substrate prepared under the conditions of 0.1 mol/L PATP, 5 h deposition in PATP and 12 h immersion in silver sol, had the best reinforcement effect (that is, uniform and compact particle arrangement and no particle clusters). By use of this substrate, the minimum detectable concentration of furfural in transformer oil was about 1.06 mg/L, which provides a new method for fast and nondestructive detection of transformer aging diagnosis.

Identification of endemic vascular plant species hotspots and the effectiveness of the protected areas for their conservation in Sierra Madre Oriental, Mexico

More than 50% of the Mexican flora is represented by 11,001 species of endemic vascular plants. These high levels of endemisms should be a primal criterion for the recognition of areas for conservation. However, it is unknown whether the current network of protected areas guarantees the conservation of endemic vascular plant species. We focused in the Sierra Madre Oriental (SMOr), a mountain chain along Eastern Mexico that is recognized as one of the most important hotspots of vascular plant endemism in the country. At present, SMOr includes 73 protected areas, but their effectiveness for conservation of endemic species has not been evaluated. We aimed to calculate the number of endemic species that are currently considered in protection areas and propose the recognition of new areas that may include a greater endemic species diversity. Hotspots of endemism in SMOr were identified using herbaria information of 734 endemic species. The location of hotspots were identified from distribution patterns generated in the program MaxEnt. Also, Marxan program to reconstruct a map to propose new protected areas that include a greater number of endemic species. We observed that the richest hotspots are located in broken terrains with temperate or semi-arid climates, chalky soils, and a mixture of forests and scrublands featuring pines and oaks. When considering that at least 10% of the geographic distribution of each species should be conserved, the current protection areas include 66% of the endemic species, which might be an acceptable percentage, although it excludes an important number of potentially threatened species. Therefore, we propose the recognition of ten more areas that might be promising for the conservation of the remaining 34% of endemic plants in SMOr. This study demonstrates that current efforts for conservation in Mexico may be greatly improved when considering the hotspots of vascular plant endemisms.

Functional rarity of coral reef fishes at the global scale: Hotspots and challenges for conservation

Characterizing functional diversity has become central in ecological research and for biodiversity assessment. Understanding the role of species with rare traits, i.e. functionally rare species, in community assembly, ecosystem dynamics and functioning has recently gained momentum. However, functional rarity is still ignored in conservation strategies.Here, we quantified global functional and evolutionary rarity for 2073 species of coral reef fishes and compared the rarity values to IUCN Red List status. Most species were functionally common but geographically rare. However, we found very weak correlation between functional rarity and evolutionary rarity. Functional rarity was highest for species classified as not evaluated or threatened by the IUCN Red List. The location of functional rarity hotspots (Tropical Eastern Pacific) did not match hotspots of species richness and evolutionary distinctiveness (Indo-Australian Archipelago), nor the currently protected areas. We argue that functional rarity should be acknowledged for both species and site prioritization in conservation strategies.

How green was my valley: forest canopy density in relation to topography and anthropogenic effects in Manipur valley, India

ABSTRACTForest canopy density (FCD) is a major factor in the evaluation of forest status and is an important indicator of possible management interventions. The study uses the FCD model with Landsat TM and Landsat 8 OLI images to assess canopy density in India’s Manipur valley and surrounding hills. Normalized difference built-up index (NDBI) was used to extract built-up areas and population density was retrieved from LandScan data, while elevation and slope were obtained from ASTER DEMs (30 m). Four types of canopy density were delineated with crown cover above 71%, 41–70%, 11–40%, below 10% and areas with no canopy cover, that is 0%. A sharp decline in forest area occurred during 1989–2016 at a rate of loss of 2.9 % year-1 with an average rate of deforestation of 3051 ha year-1. Dense forests exhibited remarkable degradation, especially towards the central valley. The variation in the topographical (elevation and slope) gradient resulted in significant differences in the canopy density over the study area barring some hill slopes. Population pressure and various developmental activities in recent decades led to forest degradation in this fragile yet rich Eastern Himalaya biodiversity hotspot.

Global species richness of hydrobiid snails determined by climate and evolutionary history

Abstract Efforts to describe spatial patterns of freshwater diversity and to evaluate their underlying factors have traditionally been focused on some animal groups (e.g. amphibians, fish or dragonflies). Despite being a dominant component in continental aquatic ecosystems and crucial for determining priority areas for conservation, broad‐scale data on gastropod total species, endemic and threatened species richness are limited. Based on these biodiversity indices, we identify global hotspots, extinction risk along the elevational gradient and the drivers of species richness patterns in the largest group of freshwater gastropods, the family Hydrobiidae. Given the strong dependency to a nonmarine aquatic environment, the observed richness patterns of extant hydrobiid species could be significantly influenced by large‐scale geography and dispersal processes as well as climatic conditions affecting continental ecosystems. Therefore, we tested several predictions for species richness derived from ecological and evolutionary hypotheses postulated for other freshwater groups. Based on a comprehensive literature and biodiversity database review, we compiled the number of total, endemic and threatened species per freshwater ecoregion. We classified ecoregions as hotspots if each biodiversity index was in the top 25% of its range and assessed the effect of 13 environmental and evolutionary factors on species richness using generalised linear models. We identified 906 species and 157 genera of Hydrobiidae showing mainly a Nearctic–Palearctic distribution and 19 biodiversity hotspots, most located across the Mediterranean Basin. In our data set, 83% of the species were endemic to a single ecoregion. Of the 43% non‐data deficient species, we found almost three times more threatened than non‐threatened species, and extinction risk peaked at 1,500 m a.s.l. Species richness was unequally distributed over biogeographic realms, increased with higher connectivity among ecoregions, and was negatively related with annual temperature range. Latitude and precipitation seasonality explained part of the richness variation by a nonlinear relationship. The identified hotspots correspond with those of other freshwater taxa. The hump‐shaped relationship of extinction risk with elevation is likely the consequence of decreasing natural and anthropogenic perturbations at higher elevations. Global hotspots of Hydrobiidae richness represent areas of climatic stability with medium precipitation and temperature seasonality that are well connected with other hydrological basins. Our results illustrate that both evolutionary and environmental factors determine these global patterns and that future changes of the latter factors may affect hydrobiid richness.