Exploring the worldwide patterns of endemism and the processes that lead to the formation of highendemism centers is crucial in biogeography.This study examines the geographic distribution and ecological influences on...Exploring the worldwide patterns of endemism and the processes that lead to the formation of highendemism centers is crucial in biogeography.This study examines the geographic distribution and ecological influences on the endemism of liverworts across 390 regions worldwide.We assess phylogenetic endemism and relative phylogenetic endemism in relation to eleven environmental factors,which represent current and Quaternary climate variations,as well as topographic and environmental heterogeneity.Areas with higher endemism in liverworts tend to have higher temperatures,precipitation,and environmental heterogeneity,but lower temperature seasonality and lesser impacts from Quaternary climate changes.Regions exhibiting notably high endemism are predominantly found in tropical Asia,Madagascar,eastern Australia,and the Andes,while those with notably low endemism are generally in temperate Eurasia and North America,parts of Africa,and eastern South America.Centers of neo-endemism are mainly in southern Africa,whereas centers of paleo-endemism are in southern South America,tropical Asia,and New Zealand.Environment variability is a more significant predictor of phylogenetic endemism than current climate conditions,which are themselves more predictive than variables related to Quaternary climate changes.Nevertheless,these three types of explanatory variables combined explain only about one-third of the variance in phylogenetic endemism.展开更多
Gebel Katrina,located in the Saint Catherine Protectorate of South Sinai(Egypt),is a biologically rich area with diverse plant communities shaped by factors such as elevation,slope,soil type,and precipitation.This stu...Gebel Katrina,located in the Saint Catherine Protectorate of South Sinai(Egypt),is a biologically rich area with diverse plant communities shaped by factors such as elevation,slope,soil type,and precipitation.This study was designed to examine the vegetation structure,update the occurrence of endemic taxa,and investigate the impact of environmental conditions and landform types on plant disruption in the region.The primary objective of this study was to analyze the behavior and distribution of the most common species across major environmental gradients.Between 2022 and 2024,49 stands were randomly collected within the study area characterized by relatively uniform vegetation and physiography and represent as much as possible the four major landform types(terraces,slopes,ridges,and gorges).The selected stands were distributed as follows:terraces(12 stands),slopes(9 stands),ridges(9 stands),and gorges(19 stands).For the analysis of the biological spectrum,a growth-form system with four categories was utilized:trees(T),shrubs(S),perennial herbs(PH),and annual herbs(A).Soil analyses were conducted for composite samples from the 49 stands.For each recorded species,nativity,species diversity measurements,endemism,and IUCN conservation status were depicted.Multivariate analysis techniques were used to assess the classification of the 49 stands in various landforms,and ordination with soil variables were applied using different software.A total of 137 taxa were recorded from Gebel Katrina area belonging to 39 families(1 Pteridaceae,1 Ephedraceae,and 37 Angiospermae),of which 16 were endemics,which indicates the mountain's significance as a biodiversity hotspot.Of these endemic taxa,nine were classified as Endangered(EN)and four as Least Concern(LC),together accounting for over 80%of the endemic flora.The largest angiosperm families with the highest numbers of species included Asteraceae,Lamiaceae,Poaceae,Brassicaceae,Caryophyllaceae and Fabaceae.These six families constituted more than 30%of the recorded flora.Shrubs and perennial herbs were the predominant growth forms,collectively comprising over 70%of the total flora.Native taxa comprised the dominant component of the recorded flora,accounting for 80 species(58.4%of the total).In contrast,non-native taxa were limited to two annual grasses.Analysis of IUCN Red List proportions revealed a predominance of EN taxa,accounting for 52 taxa(37.9%),followed by Least Concern(LC)taxa with 36 taxa(26.3%).Together,these two categories constituted over 60%of the total assessed flora.Hierarchical cluster analysis of a presence/absence data matrix(49 stands×91 species after removal of species with occurrences<5%),using the Sørensen(Bray-Curtis)method,identified eight distinct vegetation clusters.Each cluster is characterized by one or more dominant species,distinguished by their highest percentage of occurrence(f)within their respective group.Apart from soil reaction(pH)and diversity indices(species richness and Shannon’s index),ANOVA test showed high significant differences in most of the measured environmental variables among the obtained cluster groups(A-H).Canonical Correspondence Analysis(CCA)showed direct correlations between the 7 examined environmental variables and plant species composition in Gebel Katrina.The eight cluster groups were separated along axes 1 and 2 of the diagram.The species-environment correlations were high for the three axes explaining 63.0%of the cumulative variance.The stands of groups(E)and(G)were correlated with coarse sand,stands of group(B)were highly correlated with electric conductivity(EC),and stands of group(F)were correlated with elevation.The endemic flora of Gebel Katrina faces multiple anthropogenic and environmental threats.Overgrazing by livestock,excessive harvesting of plants for fuelwood and traditional medicinal uses,and habitat degradation due to land-use changes have led to significant depletion of vegetation cover and biodiversity loss.展开更多
Orchid diversity provides a unique opportunity to further our understanding of biotic and abiotic factors linked to patterns of richness,endemism,and phylogenetic endemism in many regions.However,orchid diversity is c...Orchid diversity provides a unique opportunity to further our understanding of biotic and abiotic factors linked to patterns of richness,endemism,and phylogenetic endemism in many regions.However,orchid diversity is consistently threatened by illegal trade and habitat transformation.Here,we identified areas critical for orchid conservation in the biogeographic province of Megamexico.For this purpose,we evaluated orchid endemism,phylogenetic diversity,and phylogenetic endemism within Megamexico and characterized orchid life forms.Our results indicate that the majority of the regions with the highest estimates of endemism and phylogenetic endemism are in southern Mexico and northern Central America,mostly located on the Pacific side of Megamexico.Among the most important orchid lineages,several belong to epiphytic lineages such as Pleurothallidinae,Laeliinae and Oncidiinae.We also found that species from diverse and distantly related lineages converge in montane forests where suitable substrates for epiphytes abound.Furthermore,the southernmost areas of phylogenetic diversity and endemism of Megamexico are in unprotected areas.Thus,we conclude that the most critical areas for orchid conservation in Megamexico are located in southern Mexico and northern Central America.We recommend that these areas should be given priority by the Mexican system of natural protected areas as complementary conservation areas.展开更多
Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contri...Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this landscape.展开更多
Patterns of biodiversity and endemism are important and form the foundation for biogeography and conservation studies. Hormaphidinae is an aphid group mainly distributed in the Sino-Japanese, Oriental, and Nearctic zo...Patterns of biodiversity and endemism are important and form the foundation for biogeography and conservation studies. Hormaphidinae is an aphid group mainly distributed in the Sino-Japanese, Oriental, and Nearctic zoogeographic realms. To infer the areas of endemism of Hormaphidinae aphids in the Sino-Japanese and Oriental realms, we employed a geographical distribution dataset covering all 225 species in subfamily Hormaphidinae. In total, 1,245 distribution occurrence records for all species were analyzed in addition to the number of species in a certain grid cell to calculate species richness. Two methods （parsimony analysis of endemicity （PAE） and the use of an optimization criterion-- NDMNNDM） using a total of 6 grid sizes were applied to detect possible areas of endemism and to assess the probable effects of the 2 different methods and 6 grid sizes on the results of the patterns of the areas of endemism. The results revealed that islands presented most of the areas with high species richness and endemic species, particularly Japan, Taiwan Island, Java Island, the Malaysian Peninsula, southeast Himalaya, and the Hengduan Mountains. Most of these areas of endemism were located on islands or a peninsula. Islands were therefore shown to play an essential role in facilitating the formation of high species richness and endemism. Different grid sizes directly determined the regions of the areas of endemism, with small grid sizes tending to detect small and discrete areas of endemism and large grid sizes identifying continuous areas of endemism. In terms of the two methods, NDM/VNDM was found to identify more areas of endemism than PAE.展开更多
Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here...Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here,we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world.We identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and Australia.Different categories of phylogenetic endemism centers can be differentiated using current climate conditions.Current climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,respectively.Thus our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote endemism.Our study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment.展开更多
Iran supports a great share of exotic and/or endemic plant genera and species. The genus Fritillaria(Liliaceae) is a precious part of this botanical richness with 19 species, of which 10 are endemic to the country. Ho...Iran supports a great share of exotic and/or endemic plant genera and species. The genus Fritillaria(Liliaceae) is a precious part of this botanical richness with 19 species, of which 10 are endemic to the country. However, signs are mounting that the country is truly at a crossroads when it comes to preservation of this national wealth. In this regard, an effective conservation strategy should thoroughly consider the classification of Fritillaria, as conservation practices are compromised by knowledge gaps in systematics and taxonomy. As published studies on Fritillaria in Iran have been sporadic and limited in scope, the aim of this review is to provide information necessary to help bridge these information gaps.Our objective is to facilitate increased understanding of the geographic, taxonomic, cytogenetic and phylogenetic status of Iranian Fritilloria, which is vital to meeting the goal of sustainable conservation of the genus in Iran and neighboring areas.展开更多
The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies.However, there is no comprehen...The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies.However, there is no comprehensive study from a rigorous phylogenetic perspective to understand patterns of diversity and endemism and to guide biodiversity conservation in China. We conducted a spatial phylogenetic analysis of the Chinese angiosperm flora at the generic level to identify centers of neo-and paleoendemism. Our results indicate that:(i) themajority of grid cells in China with significantly high phylogenetic endemism(PE) were located in the mountainous regions;(ii) four of the nine centers of endemism recognized, located in northern and western China, were recognized for the first time;(iii) arid and semiarid regions in Northwest China were commonly linked to significant PE, consistent with other spatial phylogenetic studies worldwide;and(iv) six highpriority conservation gaps were detected by overlaying the boundaries of China’s nature reserves on all significant PE cells. Overall, we conclude that the mountains of southern and northern China contain both paleo-endemics(ancient relictual lineages) and neo-endemics(recently diverged lineages). The areas we highlight as conservation priorities are important for broad-scale planning, especially in the context of evolutionary history preservation.展开更多
This study identifies'centers of endemism'for typhlocybine leafhoppers in China,revealing diversity patterns and congruence of patterns between total species rich-ness and endemism.Distribution patterns of 774...This study identifies'centers of endemism'for typhlocybine leafhoppers in China,revealing diversity patterns and congruence of patterns between total species rich-ness and endemism.Distribution patterns of 774 Typhlocybinae(607 described and 167 undescribed species)were mapped on a 1.5°×1.5°latitude/longitude grid.Total species richness,endemic species richness and weighted endemism richness were calculated for each grid cell.Grid cells within the top 5%highest values of weighted endemism richness were considered as'centers of endemism'.Diversity patterns by latitude and altitude were obtained through calculating the gradient richness.A congruence of diversity patterns between total species richness and endemism was confirmed using correlation analysis.To investigate the bioclimatic factors(19 variables)contributing to the congruence be-tween total species richness and endemism,we compared the factor's difference between non-endemic and endemic species using the Kruskal-Wallis test.Eleven centers of en-demism,roughly delineated by mountain ranges,were identified in central and southern China,including the south Yunnan,Hengduan Mountains,Qinling Mountains,Hainan Is-land,Taiwan Island and six mountain areas located in western Sichuan,northwest Fujian,southeast Guizhou,southeast Hunan,central and western Guangdong,and north Zhejiang.Total species richness and endemic species richness decreased with increased latitude and had a consistent unimodal response to altitude.The proportions of endemism decreased with increased latitude and increased with rising altitude.Diversity patterns between total species richness and endemism were highly consistent,and'Precipitation of Coldest Pe-riod'and'Temperature of Coldest Period'may contribute to the congruence of pattern.Migration ability may play a role in the relationship of endemism and species richness;climate,environment factors and important geologic isolation events can also play crucial effects on relationships under special conditions.展开更多
The present paper analyzed 239 endemic genera in 67 families in the flora of seed plants in China.The results showed that there are five families containing more than ten endemic genera,namely,Gesneriaceae(27),which h...The present paper analyzed 239 endemic genera in 67 families in the flora of seed plants in China.The results showed that there are five families containing more than ten endemic genera,namely,Gesneriaceae(27),which hereafter refers to the number of endemic genera in China,Composite(20),Labiatae(12),Cruciferae(11),and Umbelliferae(10),15 families with two endemic genera,and another 30 families with only one endemic genus.Four monotypic families(Ginkgoaceae,Davidiaceae,Eucommiaceae and Acanthochlamydaceae)are the most ancient,relict and characteristic in the flora of seed plants in China.Based on integrative data of systematics,fossil history,and morphological and molecular evidence of these genera,their origin,evolution and relationships were discussed.In gymnosperms,all endemic genera are relicts of the Arctic-Tertiary flora,having earlier evolutionary history,and can be traced back to the Cretaceous or to the Jurassic and even earlier.In angiosperms,the endemic genera are mostly relicts,and are represented in all lineages in the“Eight-Class System of Classification of Angiosperms”,and endemism can be found in almost every evolutionary stage of extant angiosperms.The relict genera once occupied huge areas in the northern hemisphere in the Tertiary or the late Cretaceous,while neo-endemism mostly originated in the late Tertiary.They came from Arctic-Tertiary,Paleo-tropical-Tertiary and Tethys-Tertiary florisitic elements,and the blend of the three elements with many genera of autochthonous origin.The endemism was formed when some dispersal routes such as the North Atlantic Land Bridge,and the Bering Bridge became discontinuous during the Tertiary,as well as the climate change and glaciations in the late Tertiary and the Quaternary.Therefore,the late Tertiary is the starting point of extant endemism of the flora in China.展开更多
China lies at the heart of the global center of freshwater crab diversity in tropical Asia,where the 2 most diverse families occur:Potamidae(505 species,95 genera)and Gecarcinucidae(344 species,59 genera).China stands...China lies at the heart of the global center of freshwater crab diversity in tropical Asia,where the 2 most diverse families occur:Potamidae(505 species,95 genera)and Gecarcinucidae(344 species,59 genera).China stands out as the country with the highest species richness of freshwater crabs globally.Its fauna comprises 243 species in 37 genera and in 2 families,and species discovery is still progressing at a rapid pace.The vast majority of the species are distributed in southwest,south central and eastern China in the Oriental zoogeographical region.China also stands out as having a highly endemic freshwater crab fauna at the species level(96%)and at the genus level(78%).Although the recent International Union for the Conservation of Nature(IUCN)red list conservation assessment found only 6 out of 228 species(2%)to be threatened(5 potamids and 1 gecarcinucid),the majority(more than 75%)of Chinese species are regarded as data deficient,so the number of threatened species is likely to be a serious underestimate.Threats from increasing habitat destruction and pollution are a major concern due to the rapidly growing economy and massive developments taking place in China.There is therefore an urgent need for increased species exploration and for the development of a conservation strategy for China’s threatened(and potentially threatened)endemic freshwater crab species.展开更多
A community composition island biogeography model was developed to explain and predict two community patterns （beta diversity and endemism） with the consideration of speciation, extinction and dispersal processes. R...A community composition island biogeography model was developed to explain and predict two community patterns （beta diversity and endemism） with the consideration of speciation, extinction and dispersal processes. Results showed that rate of speciation is positively and linearly associated with beta diversity and endemism, that is, increasing species rates typically could increase the percentage of both endemism and beta diversity. The influences of immigration and extinction rates on beta diversity and endemism are nonlinear, but with numerical simulation, I could observe that increasing extinction rates would lead to decreasing percentage of endemism and beta diversity. The role of immigration rate is very similar to that of speciation rate, having a positive relationship with beta diversity and endemism. Finally, I found that beta diversity is closely related to the percentage of endemism. The slope of this positive relationship is determined jointly by different combinations of speciation, extinction and immigration rates.展开更多
文摘Exploring the worldwide patterns of endemism and the processes that lead to the formation of highendemism centers is crucial in biogeography.This study examines the geographic distribution and ecological influences on the endemism of liverworts across 390 regions worldwide.We assess phylogenetic endemism and relative phylogenetic endemism in relation to eleven environmental factors,which represent current and Quaternary climate variations,as well as topographic and environmental heterogeneity.Areas with higher endemism in liverworts tend to have higher temperatures,precipitation,and environmental heterogeneity,but lower temperature seasonality and lesser impacts from Quaternary climate changes.Regions exhibiting notably high endemism are predominantly found in tropical Asia,Madagascar,eastern Australia,and the Andes,while those with notably low endemism are generally in temperate Eurasia and North America,parts of Africa,and eastern South America.Centers of neo-endemism are mainly in southern Africa,whereas centers of paleo-endemism are in southern South America,tropical Asia,and New Zealand.Environment variability is a more significant predictor of phylogenetic endemism than current climate conditions,which are themselves more predictive than variables related to Quaternary climate changes.Nevertheless,these three types of explanatory variables combined explain only about one-third of the variance in phylogenetic endemism.
文摘Gebel Katrina,located in the Saint Catherine Protectorate of South Sinai(Egypt),is a biologically rich area with diverse plant communities shaped by factors such as elevation,slope,soil type,and precipitation.This study was designed to examine the vegetation structure,update the occurrence of endemic taxa,and investigate the impact of environmental conditions and landform types on plant disruption in the region.The primary objective of this study was to analyze the behavior and distribution of the most common species across major environmental gradients.Between 2022 and 2024,49 stands were randomly collected within the study area characterized by relatively uniform vegetation and physiography and represent as much as possible the four major landform types(terraces,slopes,ridges,and gorges).The selected stands were distributed as follows:terraces(12 stands),slopes(9 stands),ridges(9 stands),and gorges(19 stands).For the analysis of the biological spectrum,a growth-form system with four categories was utilized:trees(T),shrubs(S),perennial herbs(PH),and annual herbs(A).Soil analyses were conducted for composite samples from the 49 stands.For each recorded species,nativity,species diversity measurements,endemism,and IUCN conservation status were depicted.Multivariate analysis techniques were used to assess the classification of the 49 stands in various landforms,and ordination with soil variables were applied using different software.A total of 137 taxa were recorded from Gebel Katrina area belonging to 39 families(1 Pteridaceae,1 Ephedraceae,and 37 Angiospermae),of which 16 were endemics,which indicates the mountain's significance as a biodiversity hotspot.Of these endemic taxa,nine were classified as Endangered(EN)and four as Least Concern(LC),together accounting for over 80%of the endemic flora.The largest angiosperm families with the highest numbers of species included Asteraceae,Lamiaceae,Poaceae,Brassicaceae,Caryophyllaceae and Fabaceae.These six families constituted more than 30%of the recorded flora.Shrubs and perennial herbs were the predominant growth forms,collectively comprising over 70%of the total flora.Native taxa comprised the dominant component of the recorded flora,accounting for 80 species(58.4%of the total).In contrast,non-native taxa were limited to two annual grasses.Analysis of IUCN Red List proportions revealed a predominance of EN taxa,accounting for 52 taxa(37.9%),followed by Least Concern(LC)taxa with 36 taxa(26.3%).Together,these two categories constituted over 60%of the total assessed flora.Hierarchical cluster analysis of a presence/absence data matrix(49 stands×91 species after removal of species with occurrences<5%),using the Sørensen(Bray-Curtis)method,identified eight distinct vegetation clusters.Each cluster is characterized by one or more dominant species,distinguished by their highest percentage of occurrence(f)within their respective group.Apart from soil reaction(pH)and diversity indices(species richness and Shannon’s index),ANOVA test showed high significant differences in most of the measured environmental variables among the obtained cluster groups(A-H).Canonical Correspondence Analysis(CCA)showed direct correlations between the 7 examined environmental variables and plant species composition in Gebel Katrina.The eight cluster groups were separated along axes 1 and 2 of the diagram.The species-environment correlations were high for the three axes explaining 63.0%of the cumulative variance.The stands of groups(E)and(G)were correlated with coarse sand,stands of group(B)were highly correlated with electric conductivity(EC),and stands of group(F)were correlated with elevation.The endemic flora of Gebel Katrina faces multiple anthropogenic and environmental threats.Overgrazing by livestock,excessive harvesting of plants for fuelwood and traditional medicinal uses,and habitat degradation due to land-use changes have led to significant depletion of vegetation cover and biodiversity loss.
基金The study was carried out with the support of CONACyT,which awarded an M.Sc.scholarship to BEGR(CVU935962)through the Instituto de Ecología,A.C.
文摘Orchid diversity provides a unique opportunity to further our understanding of biotic and abiotic factors linked to patterns of richness,endemism,and phylogenetic endemism in many regions.However,orchid diversity is consistently threatened by illegal trade and habitat transformation.Here,we identified areas critical for orchid conservation in the biogeographic province of Megamexico.For this purpose,we evaluated orchid endemism,phylogenetic diversity,and phylogenetic endemism within Megamexico and characterized orchid life forms.Our results indicate that the majority of the regions with the highest estimates of endemism and phylogenetic endemism are in southern Mexico and northern Central America,mostly located on the Pacific side of Megamexico.Among the most important orchid lineages,several belong to epiphytic lineages such as Pleurothallidinae,Laeliinae and Oncidiinae.We also found that species from diverse and distantly related lineages converge in montane forests where suitable substrates for epiphytes abound.Furthermore,the southernmost areas of phylogenetic diversity and endemism of Megamexico are in unprotected areas.Thus,we conclude that the most critical areas for orchid conservation in Megamexico are located in southern Mexico and northern Central America.We recommend that these areas should be given priority by the Mexican system of natural protected areas as complementary conservation areas.
文摘Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this landscape.
文摘Patterns of biodiversity and endemism are important and form the foundation for biogeography and conservation studies. Hormaphidinae is an aphid group mainly distributed in the Sino-Japanese, Oriental, and Nearctic zoogeographic realms. To infer the areas of endemism of Hormaphidinae aphids in the Sino-Japanese and Oriental realms, we employed a geographical distribution dataset covering all 225 species in subfamily Hormaphidinae. In total, 1,245 distribution occurrence records for all species were analyzed in addition to the number of species in a certain grid cell to calculate species richness. Two methods （parsimony analysis of endemicity （PAE） and the use of an optimization criterion-- NDMNNDM） using a total of 6 grid sizes were applied to detect possible areas of endemism and to assess the probable effects of the 2 different methods and 6 grid sizes on the results of the patterns of the areas of endemism. The results revealed that islands presented most of the areas with high species richness and endemic species, particularly Japan, Taiwan Island, Java Island, the Malaysian Peninsula, southeast Himalaya, and the Hengduan Mountains. Most of these areas of endemism were located on islands or a peninsula. Islands were therefore shown to play an essential role in facilitating the formation of high species richness and endemism. Different grid sizes directly determined the regions of the areas of endemism, with small grid sizes tending to detect small and discrete areas of endemism and large grid sizes identifying continuous areas of endemism. In terms of the two methods, NDM/VNDM was found to identify more areas of endemism than PAE.
文摘Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here,we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world.We identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and Australia.Different categories of phylogenetic endemism centers can be differentiated using current climate conditions.Current climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,respectively.Thus our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote endemism.Our study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment.
基金Tarbiat Modares University (TMU)Research Institute of Forests and Rangelands of Iran (RIFRI) for providing financial support
文摘Iran supports a great share of exotic and/or endemic plant genera and species. The genus Fritillaria(Liliaceae) is a precious part of this botanical richness with 19 species, of which 10 are endemic to the country. However, signs are mounting that the country is truly at a crossroads when it comes to preservation of this national wealth. In this regard, an effective conservation strategy should thoroughly consider the classification of Fritillaria, as conservation practices are compromised by knowledge gaps in systematics and taxonomy. As published studies on Fritillaria in Iran have been sporadic and limited in scope, the aim of this review is to provide information necessary to help bridge these information gaps.Our objective is to facilitate increased understanding of the geographic, taxonomic, cytogenetic and phylogenetic status of Iranian Fritilloria, which is vital to meeting the goal of sustainable conservation of the genus in Iran and neighboring areas.
基金supported by grants from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31000000 and XDA19050103)the International Partnership Program of the Chinese Academy of Sciences(151853KYSB20190027)+4 种基金the National Natural Science Foundation of China(NNSF31800178,31870506,and 32122009)the Sino-Africa Joint Research Center,the Chinese Academy of Sciences CAS International Research and Education Development Program(SAJC202101)the Jiangsu Natural Science Foundation(BK20181398)the Hundred Talents Program of CAS(Y8C3041100)supported in part by the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2018QNRC001)。
文摘The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies.However, there is no comprehensive study from a rigorous phylogenetic perspective to understand patterns of diversity and endemism and to guide biodiversity conservation in China. We conducted a spatial phylogenetic analysis of the Chinese angiosperm flora at the generic level to identify centers of neo-and paleoendemism. Our results indicate that:(i) themajority of grid cells in China with significantly high phylogenetic endemism(PE) were located in the mountainous regions;(ii) four of the nine centers of endemism recognized, located in northern and western China, were recognized for the first time;(iii) arid and semiarid regions in Northwest China were commonly linked to significant PE, consistent with other spatial phylogenetic studies worldwide;and(iv) six highpriority conservation gaps were detected by overlaying the boundaries of China’s nature reserves on all significant PE cells. Overall, we conclude that the mountains of southern and northern China contain both paleo-endemics(ancient relictual lineages) and neo-endemics(recently diverged lineages). The areas we highlight as conservation priorities are important for broad-scale planning, especially in the context of evolutionary history preservation.
基金financially supported by the Educational Ministryof China(99007005,20110204110004,Z111020905)the Ministry of Science and Technology of China(2006FY120100)the National Natural Science Foun-dation of Chína for Key Projects(66216F1001).
文摘This study identifies'centers of endemism'for typhlocybine leafhoppers in China,revealing diversity patterns and congruence of patterns between total species rich-ness and endemism.Distribution patterns of 774 Typhlocybinae(607 described and 167 undescribed species)were mapped on a 1.5°×1.5°latitude/longitude grid.Total species richness,endemic species richness and weighted endemism richness were calculated for each grid cell.Grid cells within the top 5%highest values of weighted endemism richness were considered as'centers of endemism'.Diversity patterns by latitude and altitude were obtained through calculating the gradient richness.A congruence of diversity patterns between total species richness and endemism was confirmed using correlation analysis.To investigate the bioclimatic factors(19 variables)contributing to the congruence be-tween total species richness and endemism,we compared the factor's difference between non-endemic and endemic species using the Kruskal-Wallis test.Eleven centers of en-demism,roughly delineated by mountain ranges,were identified in central and southern China,including the south Yunnan,Hengduan Mountains,Qinling Mountains,Hainan Is-land,Taiwan Island and six mountain areas located in western Sichuan,northwest Fujian,southeast Guizhou,southeast Hunan,central and western Guangdong,and north Zhejiang.Total species richness and endemic species richness decreased with increased latitude and had a consistent unimodal response to altitude.The proportions of endemism decreased with increased latitude and increased with rising altitude.Diversity patterns between total species richness and endemism were highly consistent,and'Precipitation of Coldest Pe-riod'and'Temperature of Coldest Period'may contribute to the congruence of pattern.Migration ability may play a role in the relationship of endemism and species richness;climate,environment factors and important geologic isolation events can also play crucial effects on relationships under special conditions.
基金This paper was supported by Yunnan Provincial Government through an Award for Prominent Contributions in Science and Technology of Prof.Wu Zhengyi in 2001(KIB-WU-02)the Chinese Natural Science Foundation of China(Grant No.40332021)National Basic Research Program of China(No.2003CB415103).
文摘The present paper analyzed 239 endemic genera in 67 families in the flora of seed plants in China.The results showed that there are five families containing more than ten endemic genera,namely,Gesneriaceae(27),which hereafter refers to the number of endemic genera in China,Composite(20),Labiatae(12),Cruciferae(11),and Umbelliferae(10),15 families with two endemic genera,and another 30 families with only one endemic genus.Four monotypic families(Ginkgoaceae,Davidiaceae,Eucommiaceae and Acanthochlamydaceae)are the most ancient,relict and characteristic in the flora of seed plants in China.Based on integrative data of systematics,fossil history,and morphological and molecular evidence of these genera,their origin,evolution and relationships were discussed.In gymnosperms,all endemic genera are relicts of the Arctic-Tertiary flora,having earlier evolutionary history,and can be traced back to the Cretaceous or to the Jurassic and even earlier.In angiosperms,the endemic genera are mostly relicts,and are represented in all lineages in the“Eight-Class System of Classification of Angiosperms”,and endemism can be found in almost every evolutionary stage of extant angiosperms.The relict genera once occupied huge areas in the northern hemisphere in the Tertiary or the late Cretaceous,while neo-endemism mostly originated in the late Tertiary.They came from Arctic-Tertiary,Paleo-tropical-Tertiary and Tethys-Tertiary florisitic elements,and the blend of the three elements with many genera of autochthonous origin.The endemism was formed when some dispersal routes such as the North Atlantic Land Bridge,and the Bering Bridge became discontinuous during the Tertiary,as well as the climate change and glaciations in the late Tertiary and the Quaternary.Therefore,the late Tertiary is the starting point of extant endemism of the flora in China.
基金Ellie Dyer,Emma Brooks,Monica Bohm,Nadia Dewhurst and Ben Collen from the Sampled Red List Index,Zoological Society of London,UK are thanked for their help with the conservation assessments and with earlier versions of the maps of Chinese freshwater crab distributions.Hsi-Te Shih,Department of Life Science,National Chung Hsing University is thanked for providing an updated list of the freshwater crabs of China.
文摘China lies at the heart of the global center of freshwater crab diversity in tropical Asia,where the 2 most diverse families occur:Potamidae(505 species,95 genera)and Gecarcinucidae(344 species,59 genera).China stands out as the country with the highest species richness of freshwater crabs globally.Its fauna comprises 243 species in 37 genera and in 2 families,and species discovery is still progressing at a rapid pace.The vast majority of the species are distributed in southwest,south central and eastern China in the Oriental zoogeographical region.China also stands out as having a highly endemic freshwater crab fauna at the species level(96%)and at the genus level(78%).Although the recent International Union for the Conservation of Nature(IUCN)red list conservation assessment found only 6 out of 228 species(2%)to be threatened(5 potamids and 1 gecarcinucid),the majority(more than 75%)of Chinese species are regarded as data deficient,so the number of threatened species is likely to be a serious underestimate.Threats from increasing habitat destruction and pollution are a major concern due to the rapidly growing economy and massive developments taking place in China.There is therefore an urgent need for increased species exploration and for the development of a conservation strategy for China’s threatened(and potentially threatened)endemic freshwater crab species.
文摘A community composition island biogeography model was developed to explain and predict two community patterns （beta diversity and endemism） with the consideration of speciation, extinction and dispersal processes. Results showed that rate of speciation is positively and linearly associated with beta diversity and endemism, that is, increasing species rates typically could increase the percentage of both endemism and beta diversity. The influences of immigration and extinction rates on beta diversity and endemism are nonlinear, but with numerical simulation, I could observe that increasing extinction rates would lead to decreasing percentage of endemism and beta diversity. The role of immigration rate is very similar to that of speciation rate, having a positive relationship with beta diversity and endemism. Finally, I found that beta diversity is closely related to the percentage of endemism. The slope of this positive relationship is determined jointly by different combinations of speciation, extinction and immigration rates.
