Ecological divergence and synchronous Pleistocene diversification in the widespread South American butter frog complex.

Phylogeographic studies primarily focus on the major role of landscape topography in driving lineage diversification. However, populational phylogeographic breaks may also occur as a result of either niche conservatism or divergence, in the absence of geographic barriers to gene flow. Furthermore, these two factors are not mutually exclusive and can act in concert, making it challenging to evaluate their relative importances on explaining genetic variation in nature. Herein, we use sequences of two mitochondrial and four nuclear genes to investigate the timing and diversification patterns of species pertaining to the Leptodactylus latrans complex, which harbors four morphologically cryptic species with broad distributions across environmental gradients in eastern South America. The origin of this species complex dates back to the late Miocene (ca. 5.5 Mya), but most diversification events occurred synchronically during the late Pleistocene likely as the result of ecological divergence driven by Quaternary climatic oscillations. Further, significant patterns of environmental niche divergences among species in the L. latrans complex imply that ecological isolation is the primary mode of genetic diversification, mostly because phylogenetic breaks are associated with environmental transitions rather than topographic barriers at both species and populational scales. We provided new insights about diversification patterns and processes within a species complex of broadly and continuously distributed group of frogs along South America.

Temporal and spatial diversification along the Amazonia-Cerrado transition in Neotropical treefrogs of the Boana albopunctata species group.

Despite extensive research on biodiversity in Neotropical forests, biodiversity in seasonally dry, open biomes in South America has been underestimated until recently. We leverage a widespread group, Boana albopunctata, to uncover cryptic lineages and investigate the timing of diversification in Neotropical anurans with a focus on dry diagonal biomes (Cerrado, Caatinga and Chaco) and the ecotone between Amazonia and the Cerrado. We inferred a multilocus phylogeny of the B. albopunctata species group that includes 15 of 18 described species, recovered two cryptic species, and reconstructed the timing of diversification among species distributed across multiple South American biomes. One new potential species (B. aff. steinbachi), sampled in the Amazonian state of Acre, clustered within the B. calcara-fasciata species complex and is close to B. steinbachi. A second putative new species (B. aff. multifasciata), sampled in the Amazonia-Cerrado ecotone, is closely related to B. multifasciata. Lastly, we place a recently identified Cerrado lineage (B. aff. albopuncata) into the B. albopunctata species group phylogeny for the first time. Our ancestral range reconstruction showed that species in the B. albopuctata group likely dispersed from Amazonia-Cerrado into the dry-diagonal and Atlantic Forest. Intraspecies demography showed, for both B. raniceps and B. albopunctata, signs of rapid expansion across the dry diagonal. Similarly, for one clade of B. multifasciata, our analyses support an invasion of the Cerrado from Amazonia, followed by a rapid expansion across the open diagonal biomes. Thus, our study recovers several recent divergences along the Amazonia-Cerrado ecotone in northern Brazil. Tectonic uplift and erosion in the late Miocene and climate oscillations in the Pleistocene corresponded with estimated divergence times in the dry diagonal and Amazonia-Cerrado ecotone. Our study highlights the importance of these threatened open formations in the generation of biodiversity in the Neotropics.

Estimating synchronous demographic changes across populations using hABC and its application for a herpetological community from northeastern Brazil.

Many studies propose that Quaternary climatic cycles contracted and/or expanded the ranges of species and biomes. Strong expansion-contraction dynamics of biomes presume concerted demographic changes of associated fauna. The analysis of temporal concordance of demographic changes can be used to test the influence of Quaternary climate on diversification processes. Hierarchical approximate Bayesian computation (hABC) is a powerful and flexible approach that models genetic data from multiple species, and can be used to estimate the temporal concordance of demographic processes. Using available single-locus data, we can now perform large-scale analyses, both in terms of number of species and geographic scope. Here, we first compared the power of four alternative hABC models for a collection of single-locus data. We found that the model incorporating an a priori hypothesis about the timing of simultaneous demographic change had the best performance. Second, we applied the hABC models to a data set of seven squamate and four amphibian species occurring in the Seasonally Dry Tropical Forests (Caatinga) in northeastern Brazil, which, according to paleoclimatic evidence, experienced an increase in aridity during the Pleistocene. If this increase was important for the diversification of associated xeric-adapted species, simultaneous population expansions should be evident at the community level. We found a strong signal of synchronous population expansion in the Late Pleistocene, supporting the increase of the Caatinga during this time. This expansion likely enhanced the formation of communities adapted to high aridity and seasonality and caused regional extirpation of taxa adapted to wet forest.

Herpetofauna of protected areas in the Caatinga VIII: An updated checklist for the Serra das Confusões region with new data from Serra Vermelha, Piauí, Brazil / Herpetofauna das áreas protegidas da Caatinga VIII: Um inventário atualizado para a região da Serra das Confusões com novos dados da Serra Vermelha, Piauí, Brazil

Abstract It is repeatedly stressed the need to characterize the extant biodiversity in tropical ecosystems. However, inventory studies are still progressing slowly in dry ecosystems, leading to the underestimation of their true biodiversity and hindering conservation efforts. In this study, we present primary and secondary data, along with an updated list of amphibians and reptiles from two localities in the São Francisco-Gurguéia region in Piauí. Additionally, we compare the species composition between nine areas within the Caatinga, which were sampled using standardized methods over the past ten years, to examine broader spatial patterns of community composition. To survey reptiles and amphibians, we employed similar methods and sampling efforts in two areas within the Serra das Confusões National Park (SCNP) region. Our surveys recorded a total of 73 species of amphibians and reptiles, of which 24 are new distribution records for the SCNP region. Consequently, our findings increase the known herpetofauna in the region to 94 species. Despite their proximity, the two sites in the SCNP region exhibited only 42% similarity in species composition, and they differed significantly from other areas within the Caatinga. Furthermore, even the closer Caatinga areas presented differences in species composition, highlighting the necessity to evaluate biodiversity across the landscape and contribute to understanding biogeographic patterns.

Resumo É repetidamente enfatizada a necessidade de caracterizar a biodiversidade vivente em ecossistemas tropicais. No entanto, os estudos de inventário ainda estão progredindo lentamente em ecossistemas secos, levando à subestimação de sua verdadeira biodiversidade e dificultando os esforços de conservação. Neste estudo, apresentamos dados primários e secundários, juntamente com uma lista atualizada de anfíbios e répteis de duas localidades na região de São Francisco-Gurguéia, do Piauí. Além disso, comparamos a composição de espécies entre nove áreas dentro da Caatinga, que foram amostradas usando métodos padronizados nos últimos dez anos, para examinar padrões espaciais mais amplos de composição da comunidade. Para estudar répteis e anfíbios, utilizamos métodos e esforços de amostragem semelhantes em duas áreas na região do Parque Nacional da Serra das Confusões (PNSC). Nossos levantamentos registraram um total de 73 espécies de anfíbios e répteis, das quais 24 são novos registros de distribuição para a região do PNSC. Consequentemente, nossos resultados aumentam a herpetofauna conhecida na região para 94 espécies. Apesar da proximidade, os dois locais na região do PNSC exibiram apenas 42% de similaridade na composição de espécies e diferiram significativamente de outras áreas dentro da Caatinga. Mesmo áreas mais próximas da Caatinga apresentaram diferenças na composição de espécies, destacando a necessidade de avaliar a biodiversidade em toda a paisagem e contribuir para a compreensão de padrões biogeográficos.

Anurans of the Reserva Ecológica da Michelin, Municipality of Igrapiúna, State of Bahia, Brazil / Anuros da Reserva Ecológica da Michelin, Município de Igrapiúna, Estado da Bahia, Brasil

We studied the richness and distribution of anuran species on different breeding sites at the Reserva Ecológica da Michelin (13° 50' S and 39° 10' W, approximately 90-400 m above sea level), Municipality of Igrapiúna, Bahia State, Brazil. The reserve includes fragments of Atlantic Rain Forest varying from 140 to 650 ha. Five types of environments were sampled: leaf litter inside forest fragments, streams inside forest fragments, dam on the edge of forest fragment, temporary pond inside forest, and temporary ponds inside banana and rubber groves along the eastern boundary of the reserve. We used active and passive sampling methods for surveys of amphibians, between March 2007 and December 2008. We captured 48 species distributed in 10 families (number of species in parentheses): Aromobatidae (1), Brachycephalidae (4), Bufonidae (2), Craugastoridae (1), Centrolenidae (1), Cycloramphidae (3), Hylidae (29), Leiuperidae (1), Leptodactylidae (3), and Microhylidae (3). Temporary ponds presented the highest number of species in reproductive activity (19 species in native forested areas, and 21 in plantation areas), while leaf litter presented the lowest (6 species). Two species were found in bromeliads (Phyllodytes melanomystax and P. luteolus). Twenty-two species were exclusive to fragments of forest, 11 were found only in anthropized areas (dam, and rubber and banana plantations) and 15 in both environments. Aplastodiscus cavicola and Dendropsophus giesleri had their geographic distribution extended to the State of Bahia. Phasmahyla timbo and Chiasmocleis cordeiroi known only from their type localities were found in the reserve.

Nós estudamos a riqueza e distribuição de espécies de anuros em diferentes locais de reprodução na Reserva Ecológica da Michelin (13° 50' S e 39° 10' O, aproximadamente 90-400 m acima do nível do mar), Município de Igrapiúna, Estado da Bahia, Brasil. A reserva inclui fragmentos de Mata Atlântica, variando entre 140 a 650 ha. Cinco tipos de ambientes foram amostrados: serapilheira no interior dos fragmentos de mata, córregos no interior dos fragmentos de mata, represa na borda de um fragmento de mata, poça temporária no interior de fragmento de mata e poças temporárias em seringal e bananal ao longo da margem leste da reserva. Nós usamos métodos amostrais ativos e passivos para captura dos anfíbios, entre março de 2007 e dezembro de 2008. Capturamos 48 espécies distribuídas em 10 famílias (número de espécies entre parênteses): Aromobatidae (1), Brachycephalidae (4), Bufonidae (2), Craugastoridae (1), Centrolenidae (1), Cycloramphidae (3), Hylidae (29), Leiuperidae (1), Leptodactylidae (3), and Microhylidae (3). Nas poças temporárias foi registrado o mais alto número de espécies em atividade reprodutiva (19 em áreas de floresta e 21 em áreas de plantações), enquanto a serapilheira apresentou o número mais baixo (6 espécies). Duas espécies foram encontradas em bromélias (Phyllodytes melanomystax e P. luteolus). Vinte e duas espécies foram exclusivas do interior dos fragmentos de floresta, 9 foram encontradas somente em áreas antropizadas (represa, seringais e bananais) e 15 em ambos os ambientes. Aplastodiscus cavicola e Dendropsophus giesleri tiveram suas distribuições geográficas estendidas para o Estado da Bahia. Phasmahyla timbo e Chiasmocleis cordeiroi, conhecidas somente para suas localidades-tipo, foram encontradas na reserva.