An assessment of the efficiency of protection status through determinations of biodiversity hotspots based on endemic bird species,Taiwan

Evaluations of species richness patterns have been performed at diverse scales, and biodiversity hotspots, especially endemism hotspots, have received much attention in conservation biology. We estimated the distributions of endemic bird species based on a 12-yr avian inventory project in Taiwan, identified biodiversity hotspots of endemism on a regional scale based on predictions from the ensemble forecasting framework and frequency histogram approach, and assessed the efficiency of protected areas. The results indicated that the predicted endemism hotspots were mostly located in mid- and high-elevation areas along the Central Mountain Range of Taiwan. An observed endemism hotspot was defined as one in which at least five of Taiwan's 17 endemic bird species were present. This criterion was used because the 5% of the sampled grid squares that were the richest in endemic bird species all had 5 endemic bird species or more. Seventy to seventy-one percent of the observed biodiversity hotspots matched the predicted biodiversity hotspots. This outcome was obtained whether the richness biodiversity in a grid square was based on summed predicted probability or summed predicted richness. The majority of the protected areas for these Taiwanese endemic bird species were national parks, protecting 24.1% of the predicted hotspot areas, whereas nature reserves and wildlife refuges protected less than 7%. Most of the predicted endemism hotspots were not adequately protected. We conclude that the ensemble forecasting framework and the frequency histogram approach are useful for selecting critical habitats and biodiversity hotspots for endemic species and for appraising the efficiency of the protection status provided by governments.     

Towards biodiversity hotspots effective for conserving mammals with small geographic ranges

The main goal of using global biodiversity hotspots for conservation purposes is to protect taxa with small geographic ranges because these are highly vulnerable to extinction. However, the extent to what different hotspots types are effective for meeting this goal remains controversial because hotspots have been previously defined as either the richest or most threatened and richest sites in terms of total, endemic or threatened species. In this regard, the use of species richness to set conservation priorities is widely discussed because strategies focused on this diversity measure tend to miss many of the taxa with small geographic ranges. Here we use data on global terrestrial mammal distributions to show that, hotspots of total species, endemism and threat defined in terms of species richness are effective in including 27%, 29% and 11% respectively, of the taxa with small geographic ranges. Whilst, the same hotspot types defined in terms of a simple diversity index, which is a function of species richness and range-size rarity, include 68%, 44% and 90% respectively, of these taxa. In addition, we demonstrate that index hotspot types are highly efficient because they conserve 79% of mammal species (21% more species than richness hotspot types), with 59% of species shared by three hotspot types (31% more than richness hotspot types). These results suggest that selection of different diversity measures to define hotspots may strongly affect the achievement of conservation goals.     

基于系统发育的黄土高原地区木本植物多样性及特有性格局

黄土高原地区植被类型多样, 森林、草原和荒漠在此交汇并逐渐过渡。由于水热条件限制和人类活动加剧, 该地区生态环境脆弱, 生物多样性保护面临的形势日益严峻, 因此获取该区域物种多样性的空间分布格局并阐明其影响因素成为该地区生物多样性保护的首要任务。本研究首先结合标本采集记录与环境因子, 利用物种分布模型获取了293种木本植物的潜在分布区, 分析了物种丰富度和物种加权特有性的空间格局。其次, 引入系统发育信息, 分析系统发育多样性和系统发育特有性的空间格局, 并进一步利用环境因子对上述格局分别进行解释。最后, 对黄土高原地区的特有中心性质和显著性进行分析。结果表明, 生物多样性热点地区均出现在黄土高原南部水热条件较好的地区, 即秦岭和中条山一带。本区域的生物多样性空间格局由年平均降水量和最冷月最低温主导, 符合植物区系交汇带的特点。特有中心集中在南部地区和青海省, 由南向北分别是古特有中心和混合特有中心, 不存在单独的新特有中心。黄土高原地区木本植物起源较为古老, 生物多样性格局的形成以来源于热带或亚热带的物种扩散为主, 物种的分化不占主导地位。上述结果表明了将植物的进化历史纳入生物多样性保护的重要性。     

Fern and lycophyte diversity in the Pacific Northwest: Patterns and predictors

Recent floristic efforts in the Pacific Northwest (PNW) have now made it possible to characterize the broad‐scale patterns of fern and lycophyte diversity across this large and geologically‐complex region of western North America. The physiography of the PNW has been developing for over 200 million years, but Pleistocene glaciation‐induced migrations and recolonizations have strongly influenced the assembly of the flora. With the high dispersal potential of fern and lycophyte spores, the distribution patterns of pteridophytes may be representative of habitat suitability more than dispersal constraints. Our objective was to describe the biodiversity of pteridophytes in the PNW, determine the spatial distribution of that biodiversity in terms of phylogenetic diversity, identify centers of regional endemism, explore the correlations between biodiversity and environmental variables, and infer possible influences of past glaciation on the pteridophyte flora. We obtained presence‐only distribution data from two online databases. A phylogenetic tree was constructed using chloroplast DNA sequence data from GenBank. We used the Biodiverse software package to estimate and map phylogenetic diversity and phylogenetic endemism across the PNW, and to identify those regions of the PNW where diversity was higher or lower than expected in comparison to randomization models. Environmental correlates of diversity were identified using principal components analysis with bioclimatic data from WorldClim.org, and we used Maxent to predict habitat suitability for species under past and future climate conditions. We found evidence for the influence of past glaciations and glacial refugia on the patterns of pteridophyte diversity, that moisture availability and cold temperatures are strongly correlated with patterns of genus richness, phylogenetic diversity, and phylogenetic endemism. We infer that the topographic complexity of the region may be driving the assembly of the pteridophyte flora indirectly by influencing climate and precipitation patterns.     

Historical plant records enlighten the conservation efforts of ferns and Lycophytes’ diversity in tropical China

Historical records, e.g., herbarium vouchers, contain information about species distribution since the early days of the scientific exploration of floras until today. These data provide crucial evidence to map the biodiversity of the area of interest and most importantly enable the evaluation of the conservation effectiveness for a given group of organisms. This study aimed to explore the ferns and lycophytes’ diversity of Xishuangbanna Dai Autonomous Prefecture in tropical China with special emphasis on conservation efforts provided by the currently established protected areas (PAs). Instead of relying exclusively on current observation, the database was compiled from digitalized herbarium vouchers and publications being explored with special attention on the temporal and spatial dimensions of collecting efforts. Utilizing the indices including species richness, weighed endemism, corrected weighted endemism, and beta diversity, hotspots of ferns and lycophytes’ diversity were identified. In turn, the proportion of hotspots located outside PAs was estimated as a measure of conservation gaps in Xishuangbanna. Our results revealed a long collecting history of ferns and lycophytes in Xishuangbanna and this prefecture accumulated a considerable number of historical records covering 20.2 % of Chinese and 3.6% of global fern diversity. The accumulation of historical records showed strong parallelism to the historical events shaping modern China. The spatial distribution of ferns and lycophytes in Xishuangbanna was characterized by a concentration of species richness in southern valleys and endemism in western and northern mountains. In terms of conservation, existing PAs showed higher effectiveness in the protection of species richness, whereas lower effectiveness was observed in the protection of endemism and beta diversity. Our research provided a key reference for understanding the diversity and conservation of ferns and lycophytes in Xishuangbanna, as well as highlighting the locality for future collecting and conservation efforts.     

Patterns of species richness and turnover in endemic amphibians of the Guineo-Congolian rain forest

Aim

The African Guineo-Congolian (GC) region is a global biodiversity hotspot with high species endemism, bioclimatic heterogeneity, complex landscape features, and multiple biogeographic barriers. Bioclimatic and geographic variables influence global patterns of species richness and endemism, but their relative importance varies across taxa and regions and is poorly understood for many faunas. Here, we test the hypothesis that turnover in endemic amphibians of the GC biodiversity hotspot is influenced mainly by the geographic distance between grid cells and secondarily by rainfall- and temperature-related variables.

Location

West and Central Africa.

Major Taxa Studied

Amphibians.

Methods

We compiled species-occurrence records via field sampling, online databases, and taxonomic literature. Our study used 1205 unique georeferenced records of 222 amphibian species endemic to the GC region. Patterns of species richness were mapped onto a grid with a spatial resolution of 0.5° × 0.5°. We estimated weighted endemism and tested whether endemism was higher than the expected species richness (randomization test). We quantified species turnover using generalized dissimilarity modelling to evaluate the processes underlying observed patterns of species richness in GC endemic amphibians. We explored bioregionalization using agglomerative hierarchical clustering based on the unweighted pair group method with arithmetic averages.

Results

We identified seven areas within the lower GC region – forests in Cameroon, Gabon, Southern Nigeria, Equatorial Guinea, Republic of Congo, Democratic Republic of Congo, and Cote d'Ivoire – as having high species richness of endemic amphibians. The randomization test returned four major areas of significant weighted endemism: Nigeria-Cameroon mountains, forest regions of the Democratic Republic of Congo, Cote d'Ivoire, and Ghana. Our analysis revealed five bioregions for amphibian endemism, four of which were located within the lower Guineo-Congolian forest. Species turnover was strongly related to the geographic distance between grid cells; contributing bioclimatic variables included precipitation of the warmest quarter, mean temperature of the wettest quarter, and mean diurnal temperature range.

Main Conclusions

Our results indicate that geographic distance between grid cells is the primary determinant of turnover in GC endemic amphibians, with secondary but significant effects of rainfall- and temperature-related variables. Our study identifies key areas of endemic amphibian richness that could be prioritized for conservation actions.     

Biodiversity hotspots, centres of endemicity, and the conservation of coral reefs

On land, biodiversity hotspots typically arise from concentrations of small‐range endemics. For Indo‐Pacific corals and reef fishes, however, centres of high species richness and centres of high endemicity are not concordant. Moreover ranges are not, on average, smaller inside the Central Indo‐Pacific (CI‐P) biodiversity hotspot. The disparity between richness and endemicity arises because corals and reef fishes have strongly skewed range distributions, with many species being very widespread. Consequently, the largest ranges overlap to generate peaks in species richness near the equator and the CI‐P biodiversity hotspot, with only minor contributions from endemics. Furthermore, we find no relationship between the number of coral vs. fish endemics at locations throughout the Indo‐Pacific, even though total richness of the two groups is strongly correlated. The spatial separation of centres of endemicity and biodiversity hotspots in these taxa calls for a two‐pronged management strategy to address conservation needs.     

Species richness,endemism and conservation of Mexican gymnosperms

An analysis of the distribution patterns of 124 Mexican gymnosperm species was undertaken, in order to detect the Mexican areas with high species richness and endemism, and with this information to propose areas for conservation. Our study includes an analysis of species richness, endemism and distributional patterns of Mexican species of gymnosperms based on three different area units (states, biogeographic provinces and grid-cells of 1° × 1° latitude/longitude). The richest areas in species and endemism do not coincide; in this way, the Sierra Madre Oriental province, the state of Veracruz and a grid-cell located in the state of Oaxaca were the areas with the highest number of species, whereas the Golfo de México province, the state of Chiapas and a grid-cell located in this state were the richest areas in endemic species. A weighted endemism and corrected weighted endemism indices were calculated, and those grid-cells with high values in both indices and with high species richness were considered as hotspots; these grid-cells are mainly located in Southern and Central Mexico.     

Biogeographic analysis of endemic cacti of the Sierra Madre Oriental, Mexico

The distribution of cacti species that inhabit the Sierra Madre Oriental (SMO) was analysed. Grid-cells were analysed using parsimony analysis of endemicity (PAE) and endemism indices. Areas characterized by their diagnostic species were determined, aiming to propose areas for the conservation of threatened cacti. Distributional data were obtained from 1936 herbarium specimens, electronic information, and from field collections. Eight areas of endemism and three main clades were obtained from the grid-cell analysis. Areas obtained from the endemism indices are very similar to those obtained with the PAE, but differ in the association of grid-cells. PAE showed endemism patterns indicating that southern and central sections of the SMO province are the areas richest in geographically-restricted species. The results obtained with different endemism indices detected more or less the same areas, although the importance level is different. The corrected weighted endemism index can be considered as a reliable measure of endemism because it is unrelated to species richness. A regionalization of the SMO in three subprovinces is suggested, supported by characteristic cacti taxa and the existence of natural barriers.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 373–389.     

Richness and endemism in Asclepiadoideae (Apocynaceae) from the Espinhaço Range of Minas Gerais, Brazil – a conservationist view

The Espinhaço Range, located in the states of Minas Gerais andBahia, has a type of vegetation with one of the highest degrees of endemism inBrazil: the campos rupestres. In this area, Asclepiadoideaeis among the most diverse angiosperm groups, including species with broaddistributions and others restricted to small areas. This study attempts toevaluate the species richness and the degree of endemism in this region, as wellas the influence of collecting efforts on the perception of biodiversity. It isbased especially on the Asclepiadoideae from the Espinhaço Range of MinasGerais (ERMG), though a brief consideration of the situation in Bahia is alsointroduced. For comparative studies, the ERMG was divided into four regions:South, Serra do Cipó, Diamantina Plateau, and North. The species werethen characterized according to their distribution and occurrence in each ofthese regions. Ninety-seven species of Asclepiadoideae are native to the ERMG;about 30% of them are endemic to this area and almost 25% are restricted to onlyone of the four regions. The Serra do Cipó and the Diamantina Plateaupresent the highest degrees of endemism, and the highest richness innumber of species is found in the South. Nevertheless, there is a progressive decrease in collectingefforts northwards, which may distort species distribution and occurrence, andlead to misinterpretations about centers of diversity and endemism. TheEspinhaço Range should be considered vulnerable in its entirety becauseof the singular flora still incompletely known and the restricted distributionof many species. Programs that establish priority areas of conservation withoutconsidering the region as a whole will only offer temporary, partial protectionfor its biodiversity.     

Sampling effort and species richness assessment: a case study on Brazilian spiders

The knowledge on the geographical distribution of species is essential for building biogeographical and macroecological hypotheses. However, information on this regard is not distributed uniformly in space and usually come from biased sampling. The aim of this study is to quantify the influence of spatial distribution of sampling effort on the assessment of spider species richness in Brazil. We used a database of spider distribution records in Brazil, based on the taxonomic and biodiversity survey literature. The results show that the Atlantic Forest was better sampled and had the highest spider species richness among the Brazilian biomes. The Amazon, though having large collecting gaps and high concentration of records around major cities and rivers, showed the second highest number of species. The Pampa had a large number of records, but these are concentrated near a major city in the transition zone with the Atlantic Forest. The Cerrado, Caatinga and Pantanal had shown to be poorly sampled and, consequently, were among the lesser known biomes regarding the spider fauna. A linear regression analysis showed that the spider species richness in Brazil is strongly correlated to the number of records. However, we have identified areas potentially richest in species, which strongly deviate from the predicted by our analyses. Our results show that it is possible to access the spatial variation in species richness, as long as the variation in sampling effort is taken into account.     

Centers of endemism and diversity patterns for typhlocybine leafhoppers （Hemiptera： Cicadellidae： Typhlocybinae） in China

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 effect     

Global patterns in species richness of pelagic seabirds: the Procellariiformes

Quantitative information on large scale spatial patterns of biodiversity remains poor, especially for pelagic systems. In this paper the regional diversity of procellariiforms is mapped worldwide at the species level. These seabirds do not display a conventional latitudinal gradient of decreasing species richness towards high latitudes, but rather are most speciose between 37° and 59°S in all ocean basins. Based on data for foraging ranges, areas with the highest species richness and the most species with smaller range sizes are all found in the vicinity of New Zealand and its sub-Antarctic islands. In contrast, data for breeding ranges show islands in the southern Indian and Atlantic oceans to have the highest number of breeding species, while these islands and New Zealand have the most species with smaller range sizes. No northern hemisphere regions are amongst the top ten grid cells for foraging and breeding species richness, although Hawaii has the highest species richness of procellariilforms north of the equator. Northern Baja California. Madeira, the Canary islands, and the west coast of South America are all important sites of narrow endemism in the northern hemisphere. High species richness and narrow endemism coincide with areas of significant longline fishing activity in the southern hemisphere. Near-minimum sets based on one and three representations demonstrate that if all procellariiform species are to be retained, large areas of the ocean and almost all breeding sites require conservation.     

Spatial analysis of endemism to redefine conservation areas in Western Ghats (India)

A meaningful effort for the preservation of endemism would require a deep understanding of its related mechanisms and an accurate estimation of its spatial distribution. Here, we applied methods dedicated to species distribution modelling (SDM) to map an integrated index in India's Western Ghats biodiversity hotspot, the endemic tree richness, and to use it for recommendations of protected areas. We then rigorously compared SDM results with spatially explicit and multiscale comparison tools, among them the cutting-edge correlation map and profile (CMP) technique, to finally draw up an endemic richness map with improved accuracy.The endemic richness showed a sharply increasing southward gradient in the Western Ghats, mainly driven by the seasonality of the temperature and the precipitation's stability. This precise quantification of the tree endemism pattern in peninsular India helped in identifying vulnerable areas in terms of conservation of biodiversity as a whole. The Indian authorities recently used our recommendations to extend protected areas in the southern tip of the Indian peninsula to conserve this endemic richness. We believe that spatial analyses and multiscale comparison tools such as those presented here can help conservationists everywhere to better cope with the difficulties met in identifying zones for protected status.     

Evaluating the sampling bias in pattern of subterranean species richness: combining approaches

We investigated the pattern of species richness of obligate subterranean (troglobiotic) beetles in caves in the northwestern Balkans, given unequal and biased sampling. On the regional scale, we modeled the relationship between species numbers and sampling intensity using an asymptotic Clench (Michaelis–Menten) function. On the local scale, we calculated Chao 2 species richness estimates for 20 × 20 km grid cells, and investigated the distribution of uniques, species found in only one cave within the grid cell. Cells having high positive residuals, those with above average species richness than expected according to the Clench function, can be considered true hotspots. They were nearly identical to the observed areas of highest species richness. As sampling intensity in a grid cell increases the expected number of uniques decreases for any fixed number of species in the grid cell. High positive residuals show above average species richness for a certain level of sampling intensity within a cell, so further sampling has the most potential for additional species. In some cells this was supported by high numbers of uniques, also indicating insufficient sampling. Cells with low negative residuals have fewer species than would be expected, and some of them also had a low number of uniques, both indicating sufficient sampling. By combining different analyses in a novel way we were able to evaluate observed species richness pattern as well as identify, where further sampling would be most beneficial. Approach we demonstrate is of broad interest to study of biota with high levels of endemism, small distribution ranges and low catchability.     

Scale-dependence of the correlation between human population and the species richness of stream macro-invertebrates

Recent biogeographical studies have shown positive correlations between plant/vertebrate species richness and human population presence. The same pattern has been reported for Ephemeroptera (mayflies), Plecoptera (stoneflies) and Trichoptera (caddisflies) (EPT) amongst European countries. This is surprising as EPT are bio-indicators of stream pollution and most local studies report higher species richness of these macro-invertebrates where human influences on water quality are lower. Using a newly collated taxonomic dataset, we studied whether the species richness of EPT is related to human population size at finer resolutions (Italy's regions, provinces and 10×10 km² UTM cells) controlling for sampling effort, variations in area and for spatial autocorrelation. At all study grains, observed EPT species richness was strongly correlated to the number of records available for the same taxon. At the regional level, the observed number of Ephemeroptera and Plecoptera species significantly increased with increasing human population size. At the provincial level, observed species richness decreased significantly with increasing human population size for Ephemeroptera and did not vary significantly for Plecoptera and Trichoptera. At the finest grain scale, there were significant negative correlations of observed Ephemeroptera and Trichoptera species richness with human population size, although the proportion of variance explained was very low. These results were broadly confirmed when analyzing the estimated number of species using the formula of Chao2. Our analysis confirms the scale-dependence of the human population–biodiversity correlation. Over broad scales more populated regions tend to have more species than less populated ones. Restricting the study grain, the positive EPT species–people relationship disappears and turns into a negative one. Our findings suggest a challenge also for the conservation of regional EPT diversity.     

Using legumes as indicators in the seasonally dry vegetation types in South America

The South American corridor of seasonally dry vegetation (SACSV) includes different types of physiognomies forming a continuous corridor with high biodiversity and endemism; however, little attention has been paid to the conservation of the SACSV. As this is an area with great diversity, cataloguing all the species is challenging. Thus, we suggest the use of Leguminosae species (trees and shrubs) as bioindicators of the different types of vegetation present in the area and to identify priority areas for conservation of the SACSV, since the family is highly represented in this vegetation. The study area was divided into 358 grid cells with recorded specimens. For each grid cell, species richness, taxonomic diversity, number of species restricted to one type of vegetation, and threatened and indicator species of phytogeographic domain were calculated. To determine the phytogeographic domains and indicator species, analysis of similarity, cluster and indicator species (ISA) were performed. The results show that 43% of the grid cells (154) have high biological importance for conservation (high taxonomic diversity, species richness and number of restricted species), all of which lie outside of protected areas. We identified 72 indicator species for seven floristic units, which, in general, include areas of the same phytogeographic domain, supporting the existing classification systems. We suggest that for effective conservation of biodiversity present in the SACSV, it is necessary to establish protected areas throughout the SACSV.     

Elevational patterns of species richness and endemism for some important taxa in the Hengduan Mountains, southwestern China

We describe the elevational patterns of species richness and endemism of some important taxa in the Hengduan Mountains, southwest China. Species richness data came from publications, an online database, herbaria and field work. Species richness was estimated by rarefaction and interpolation. The Hengduan Mountains region was divided into a southern and northern subregion, and all species were assigned to four groups based on their distributional range within this region. The conditional autoregressive model (CAR) was used to relate species richness and explanatory variables. The elevational patterns of total, endemic and non-endemic species richness, at subregion and entire region scales, presented to be unimodal and peaked at similar elevations. Area size was strongly related with species richness, and was more powerful in explaining variation in species richness in the northern subregion than in the southern subregion. A single climatic variable (mean annual rainfall, potential evapotranspiration or moisture index) showed a weak relationship with the elevational pattern of species richness. Area and climatic variables together explained more than 67% of the variation in non-endemic richness, 53% in total richness, and 50% in endemic richness. There were three patterns of endemism at the generic level with increasing elevation: namely endemism increased, decreased, or peaked at middle elevations. All selected taxa have experienced rapid speciation and evolution within this region, which plays an important role in the uniform elevational patterns of total, endemic and non-endemic richness, and in the multiform elevational patterns of endemism. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Cross-taxon congruence in tree,bird and bat species distributions at a moderate spatial scale across four tropical forest types in the Philippines

Indicator species groups are often used as surrogates for overall biodiversity in conservation planning because inventories of multiple taxa are rare, especially in the tropics where most biodiversity is found. At coarse spatial scales most studies show congruence in the distribution of species richness and of endemic and threatened species of different species groups. At finer spatial scale levels however, cross-taxon congruence patterns are much more ambiguous. In this study we investigated cross-taxon patterns in the distribution of species richness of trees, birds and bats across four tropical forest types in a ca. 100 × 35 km area in the Northern Sierra Madre region of Luzon Island, Philippines. A non-parametric species richness estimator (Chao1) was used to compensate for differential sample sizes, sample strategies and completeness of species richness assessments. We found positive but weak congruence in the distribution of all and endemic tree and bird and tree and bat species richness across the four forest types; strong positive congruence in the distribution of all and endemic bat and bird species richness and low or negative congruence in the distribution of globally threatened species between trees, birds and bats. We also found weak cross-taxon congruence in the complementarity of pairs of forest types in species richness between trees and birds and birds and bats but strong congruence in complementarity of forest pairs between trees and bats. This study provides further evidence that congruence in the distribution of different species groups is often ambiguous at fine to moderate spatial scales. Low or ambiguous cross-taxon congruence complicates the use of indicator species and species groups as a surrogate for biodiversity in general for local systematic conservation planning.     

Arthropods in biodiversity hotspots: the case of the Phytoseiidae (Acari: Mesostigmata)

The biodiversity hotspot concept was defined by Myers in 1988 to determine priority areas for conservation. They have high endemism levels and have lost more than 70% of their original vegetated area. To date, there is little information on arthropod diversity in these zones. This work focuses on the biodiversity of the Phytoseiidae (Acari), one of the best known among the order Mesostigmata, in these threatened areas. These mites are usually predators and they are worldwide spread. Geographic distribution of phytoseiids in 27 biodiversity hostspots was assessed from data of the last world catalogue published in 2004. One thousand two hundred and thirty species are reported from at least one hotspot (62% of the total species number) and 604 species (30% of the total species number) are endemic to the 27 hotspots considered. The number of reports/publication in hotspot areas (2.6) is higher than in non-hotspot zones (1.5). Hotspots areas could be thus considered as a great reservoir of the Phytoseiidae diversity, just as they are for vertebrates and plants. Correlations between plant, vertebrate, mite diversity and endemism, as well as congruence rates between endemism levels of these three organisms suggest that the biodiversity patterns of plants and vertebrates mirror well those of the Phytoseiidae (both for endemicity and species richness). More intense conservation efforts in biodiversity hotspots would thus be assumed to affect plant and vertebrate biodiversity, as already known, but also arthropod biodiversity, as it was assumed. These results further support thus the importance of these zones in biodiversity conservation, even for organisms like mites, very small and poorly studied in this regards. More data on arthropods are, however, required to confirm these preliminary observations.