Ubirajara Oliveira

Delimiting Areas of Endemism through Kernel Interpolation

We propose a new approach for identification of areas of endemism, the Geographical Interpolation of Endemism (GIE), based on kernel spatial interpolation. This method differs from others in being independent of grid cells. This new approach is based on estimating the overlap between the distribution of species through a kernel interpolation of centroids of species distribution and areas of influence defined from the distance between the centroid and the farthest point of occurrence of each species. We used this method to delimit areas of endemism of spiders from Brazil. To assess the effectiveness of GIE, we analyzed the same data using Parsimony Analysis of Endemism and NDM and compared the areas identified through each method. The analyses using GIE identified 101 areas of endemism of spiders in Brazil GIE demonstrated to be effective in identifying areas of endemism in multiple scales, with fuzzy edges and supported by more synendemic species than in the other methods. The areas of endemism identified with GIE were generally congruent with those identified for other taxonomic groups, suggesting that common processes can be responsible for the origin and maintenance of these biogeographic units.

Strong spatial structure, Pliocene diversification and cryptic diversity in the Neotropical dry forest spider Sicarius cariri

The Brazilian Caatinga is part of the seasonally dry tropical forests, a vegetation type disjunctly distributed throughout the Neotropics. It has been suggested that during Pleistocene glacial periods, these dry forests had a continuous distribution, so that these climatic shifts may have acted as important driving forces of the Caatinga biota diversification. To address how these events affected the distribution of a dry forest species, we chose Sicarius cariri, a spider endemic to the Caatinga, as a model. We studied the phylogeography of one mitochondrial and one nuclear gene and reconstructed the paleodistribution of the species using modelling algorithms. We found two allopatric and deeply divergent clades within S. cariri, suggesting that this species as currently recognized might consist of more than one independently evolving lineage. Sicarius cariri populations are highly structured, with low haplotype sharing among localities, high fixation index and isolation by distance. Models of paleodistribution, Bayesian reconstructions and coalescent simulations suggest that this species experienced a reduction in its population size during glacial periods, rather than the expansion expected by previous hypotheses on the paleodistribution of dry forest taxa. In addition to that, major splits of intraspecific lineages of S. cariri took place in the Pliocene. Taken together, these results indicate S. cariri has a complex diversification history dating back to the Tertiary, suggesting the history of dry forest taxa may be significantly older than previously thought.

Biodiversity conservation gaps in the Brazilian protected areas

Although Brazil is a megadiverse country and thus a conservation priority, no study has yet quantified conservation gaps in the Brazilian protected areas (PAs) using extensive empirical data. Here, we evaluate the degree of biodiversity protection and knowledge within all the Brazilian PAs through a gap analysis of vertebrate, arthropod and angiosperm occurrences and phylogenetic data. Our results show that the knowledge on biodiversity in most Brazilian PAs remain scant as 71% of PAs have less than 0.01 species records per km2. Almost 55% of Brazilian species and about 40% of evolutionary lineages are not found in PAs, while most species have less than 30% of their geographic distribution within PAs. Moreover, the current PA network fails to protect the majority of endemic species. Most importantly, these results are similar for all taxonomic groups analysed here. The methods and results of our countrywide assessment are suggested to help design further inventories in order to map and secure the key biodiversity of the Brazilian PAs. In addition, our study illustrates the most common biodiversity knowledge shortfalls in the tropics.

Aranhas (Araneae, Arachnida) do Estado de São Paulo, Brasil: diversidade, esforço amostral e estado do conhecimento

In this study we present a database of spiders described and registered from the Neotropical region between 1757 and 2008. Results are focused on the diversity of the group in the State of Sao Paulo, compared to other Brazilian states. Data was compiled from over 25,000 records, published in scientific papers dealing with Neotropical fauna. These records enabled the evaluation of the current distribution of the species, the definition of collection gaps and priority biomes, and even future areas of endemism for Brazil. A total of 875 species, distributed in 50 families, have been described from the State of Sao Paulo. A total of 11,280 species have been recorded from the Neotropical region (almost 1/3 of the species described worldwide). Brazil is the Neotropical country with the highest diversity (3,203 spp.), followed by Mexico (1,951 spp.) and Panama (1,325 spp.). Seven thousand five hundred species were recorded from South America and Brazil holds the highest diversity (3,203 spp., in 72 families), followed by Argentina (1,316 spp.), and Peru (1,066 spp.).

Biogeography of Amazon birds: rivers limit species composition, but not areas of endemism

Amazonian rivers are usually suggested as dispersal barriers, limiting biogeographic units. This is evident in a widely accepted Areas of Endemism (AoEs) hypothesis proposed for Amazonian birds. We empirically test this hypothesis based on quantitative analyses of species distribution. We compiled a database of bird species and subspecies distribution records, and used this dataset to identify AoEs through three different methods. Our results show that the currently accepted Amazonian AoEs are not consistent with areas identified, which were generally congruent among datasets and methods. Some Amazonian rivers represent limits of AoEs, but these areas are not congruent with those previously proposed. However, spatial variation in species composition is correlated with largest Amazonian rivers. Overall, the previously proposed Amazonian AoEs are not consistent with the evidence from bird distribution. However, the fact that major rivers coincide with breaks in species composition suggest they can act as dispersal barriers, though not necessarily for all bird taxa. This scenario indicates a more complex picture of the Amazonian bird distribution than previously imagined.

Effectiveness of sampling methods and further sampling for accessing spider diversity: a case study in a Brazilian Atlantic rainforest fragment

The current biodiversity crisis makes the quantification of the diversity and the description of organism distribution particularly pressing. Biological inventories are among the most effective ways to improve the knowledge about local biota, but they can be very time and money‐consuming. The determination of adequate sampling effort and the selection of cost‐effective collecting methods are critical issues. In this article, a spider diversity inventory in an Atlantic semi‐deciduous forest fragment in Brazil was used to compare the efficiency of three collecting methods in two different seasons in order to propose an optimised sampling protocol. The worthiness of increasing sampling effort in the target area and similar tropical ecosystems was estimated and evaluated in terms of its cost‐effectiveness. For a better sampling of the spider community, it is suggested that a proportion of 55, 29 and 16% of total sampling hours should be dedicated to nocturnal hand collecting (NHC), pitfall traps and beating trays, respectively, in the rainy season. If only one method can be applied, the most efficient in terms of species per sampling is the NHC. A completeness of 70% of the estimated spider species richness (as predicted by the Chao1 estimator) was observed in the complete inventory and increasing sampling effort in the studied area may be highly ineffective when the costs involved are considered. Other studies in similar tropical rainforest areas also presented completeness around 70%, which might be a threshold from which the sampling effort necessary to raise the observed species richness substantially starts to be ineffective.

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.

Evolutionarily significant units of the critically endangered leaf frog Pithecopus ayeaye (Anura, Phyllomedusidae) are not effectively preserved by the Brazilian protected areas network

Abstract Protected areas (PAs) are essential for biodiversity conservation, but their coverage is considered inefficient for the preservation of all species. Many species are subdivided into evolutionarily significant units (ESUs) and the effectiveness of PAs in protecting them needs to be investigated. We evaluated the usefulness of the Brazilian PAs network in protecting ESUs of the critically endangered Pithecopus ayeaye through ongoing climate change. This species occurs in a threatened mountaintop ecosystem known as campos rupestres. We used multilocus DNA sequences to delimit geographic clusters, which were further validated as ESUs with a coalescent approach. Ecological niche modeling was used to estimate spatial changes in ESUs’ potential distributions, and a gap analysis was carried out to evaluate the effectiveness of the Brazilian PAs network to protect P. ayeaye in the face of climate changes. We tested the niche overlap between ESUs to gain insights for potential management alternatives for the species. Pithecopus ayeaye contains at least three ESUs isolated in distinct mountain regions, and one of them is not protected by any PA. There are no climatic niche differences between the units, and only 4% of the suitable potential area of the species is protected in present and future projections. The current PAs are not effective in preserving the intraspecific diversity of P. ayeaye in its present and future range distributions. The genetic structure of P. ayeaye could represent a typical pattern in campos rupestres endemics, which should be considered for evaluating its conservation status.

Publisher Correction: Biodiversity conservation gaps in the Brazilian protected areas

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Reply to Biodiversity conservation gaps in Brazil: A role for systematic conservation planning

Fonseca and Venticinque (2018, hereafter FV) present a critial assessment of a paper in which we attempt to estimate the iodiversity coverage of the Brazilian conservation units (Oliveira t al., 2017). We appreciate their contribution to this important ebate. We have no doubts that conservation planning should be ased on a variety of information sources, including not only the overage of species’ ranges but also the contribution of each area o the preservation of ecosystem services, landscape features and ocioeconomic and cultural aspects. This systematic and integraive conservation planning is certainly a complex process, which equires the contribution of experts from different fields. However, e have shown, in this reply, that our paper (Oliveira et al., 2017) ims to quantify the knowledge and protection gaps of biodiversity n protected areas, not to propose priority areas or to test whether he current proposal of priority areas is efficient. Objectives and the onclusions of our paper. We hope this short response can clarify his debate. FV’s characterizes the dataset analyzed in our paper as “. . .an rbitrary set of widespread, abundant, and nonthreatened species. . .”, nd state that any study like ours should be based on species listed s threatened in red lists. Our study was based on the best database n Brazilian biodiversity we could assemble. We have compiled ata from the literature and scientific collections of a variety of axonomic groups, and the dataset was exhaustively checked for axonomic and geographic accuracy. Thus, it is not an arbitrary et of species, but the most comprehensive database on Brazilan biodiversity assembled so far. We understand the reasons to valuate conservation gaps based only (or mostly) on threatened pecies, but in our opinion such procedure would miss an imporant portion of the Brazilian biodiversity. As we demonstrated arlier (Oliveira et al., 2016). Brazilian biodiversity is incompletely nown and this shortened data on species distribution and natral history are used to assess threat levels. Therefore, we think any species could be currently threatened but not recognized as uch due to deficient data. Arthropods (the largest group of livng forms), in particular, are poorly represented for the production f these lists. Although red lists usually include species classified s “Data Deficient”, we think only a fraction of the species curently known are effectively evaluated for the production of those ists. Thus, restricting our analyses to species officially recognized s threatened could miss a significant portion of the Brazilian bioiversity and bias our results towards better known species. Even n Europe, knowledge of threat status is incomplete, e.g., for bees: