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1.
Curr Zool ; 68(5): 535-540, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36324542

RESUMO

The climatic niche is a central concept for understanding species distribution, with current and past climate interpreted as strong drivers of present and historical-geographical ranges. Our aim is to understand whether Atlantic Forest snakes follow the general geographical pattern of increasing species climatic niche breadths with increasing latitude. We also tested if there is a tradeoff between temperature and precipitation niche breadths of species in order to understand if species with larger breadths of one niche dimension have stronger dispersal constraints by the other due to narrower niche breadths. Niche breadths were calculated by the subtraction of maximal and minimal values of temperature and precipitation across species ranges. We implemented Phylogenetic Generalized Least Squares to measure the relationship between temperature and precipitation niche breadths and latitude. We also tested phylogenetic signals by Lambda statistics to analyze the degree of phylogenetic niche conservatism to both niche dimensions. Temperature niche breadths were not related to latitude. Precipitation niche breadths decreased with increasing latitude and presented a high phylogenetic signal, that is, significant phylogenetic niche conservatism. We rejected the tradeoff hypotheses of temperature and precipitation niche breadths. Our results also indicate that precipitation should be an important ecological constraint affecting the geographical distribution of snake lineages across the South American Atlantic Forest. We then provide a general view of how phylogenetic niche conservatism could impact the patterns of latitudinal variation of climatic niches across this biodiversity hotspot.

2.
Current Zoology, v. 68, n. 5, 535-540, nov. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4339

RESUMO

The climatic niche is a central concept for understanding species distribution, with current and past climate interpreted as strong drivers of present and historical-geographical ranges. Our aim is to understand whether Atlantic Forest snakes follow the general geographical pattern of increasing species climatic niche breadths with increasing latitude. We also tested if there is a tradeoff between temperature and precipitation niche breadths of species in order to understand if species with larger breadths of one niche dimension have stronger dispersal constraints by the other due to narrower niche breadths. Niche breadths were calculated by the subtraction of maximal and minimal values of temperature and precipitation across species ranges. We implemented Phylogenetic Generalized Least Squares to measure the relationship between temperature and precipitation niche breadths and latitude. We also tested phylogenetic signals by Lambda statistics to analyze the degree of phylogenetic niche conservatism to both niche dimensions. Temperature niche breadths were not related to latitude. Precipitation niche breadths decreased with increasing latitude and presented a high phylogenetic signal, that is, significant phylogenetic niche conservatism. We rejected the tradeoff hypotheses of temperature and precipitation niche breadths. Our results also indicate that precipitation should be an important ecological constraint affecting the geographical distribution of snake lineages across the South American Atlantic Forest. We then provide a general view of how phylogenetic niche conservatism could impact the patterns of latitudinal variation of climatic niches across this biodiversity hotspot.

3.
Syst Biol, v. 20, n. 1, p. 1-25, jan. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4119

RESUMO

Brazilian continental islands represent a natural laboratory to study speciation driven by recent phenotypic and genotypic divergence. The Bothrops jararaca species group is distributed in the Brazilian Atlantic Forest and on most of the Brazilian continental islands. The group is currently composed of the mainland common lancehead (B. jararaca) and four insular species (B. alcatraz, B. insularis, B. otavioi, and B. sazimai). Here, we evaluate mitochondrial DNA and morphological diversity of the B. jararaca species group and aim to provide additional evidence to understand insularization processes on the Brazilian coast. Our results, interpreted together with a comprehensive review of geomorphological data, provide a new conceptual framework for understanding the colonization process of the Brazilian continental islands. This framework suggests a history of multiple rounds of periodic isolation and reconnection between insular populations and their mainland relatives throughout the last 420,000 years. Furthermore, although some insular populations may have speciated prior to the last glacial maximum, other species likely diverged within the last 11,000 years. Additionally, the repeated evolution of size and dietary shift in the B. jararaca species group suggests a remarkable case of convergent adaptation. Our study provides evidence that the Bothrops from Ilha da Moela (Brazilian state of São Paulo) represents an undescribed species, presenting a distinct phenotype, and an exclusive history of isolation and adaptation. We describe this unique lancehead as a new species and we suggest it should be listed as critically endangered based on its endemicity to a small island that is severely impacted by constant and longstanding human presence.

4.
Can J Zool, v. 100, n. 2, p. 147-159, jan. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4118

RESUMO

Here we describe a new species of Lancehead (Bothrops jabrensis sp. nov.) based on three individuals sampled from a previously unknown population from Pico do Jabre, an isolated and small Caatinga moist-forest enclave (CMFE) located in northeastern Brazil. Although this new species has an external morphology resembling those found in representatives of the Bothrops jararaca (Wied-Neuwied, 1824) species group, B. jabrensis can be diagnosed by a combination of meristic and color characters. Molecular phylogenetic analysis indicates the new species represents a unique and highly divergent lineage within Bothrops revealing the existence of a previously unknown phylogenetic lineage that has been evolving as an independent unit for more than 8 million years. Additionally, the estimated divergence time of this lineage conflicts with some proposed scenarios of historical processes associated with the evolution of CMFEs. Finally, the uniqueness of this species indicates its relevance for the maintenance of the phylogenetic diversity of Lanceheads in South America. Like other CMFEs, Pico do Jabre is consistently threatened by poaching, illegal fires, deforestation for agricultural purposes, and illegal logging. The restricted distribution of B. jabrensis, in a small and disturbed CMFE, strongly suggests that this species is critically endangered and is likely approaching extinction as a natural population.

5.
Herpetological Conservation and Biology, v. 16, n. 2, p. 436–451, ago. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4003

RESUMO

Habitat loss via urbanization is a cause of decline for reptile and amphibian species around the world. The Atlantic Forest is the second largest rainforest of South America and holds one of the most extraordinary herpetofauna in the world, even after decades of fragmentation. The Parque Estadual das Fontes do Ipiranga (PEFI) is one of the most important remnants of Atlantic Forest inside the city of São Paulo (Brazil), but its herpetofauna richness has not been studied. Between 2011 and 2014, we carried out a herpetofaunal inventory in the PEFI and made notes on habitat use by using pitfall traps with drift fences combined with acoustic and visual encounter surveys. We also collected data from opportunistic encounters and historical information from scientific collections. We found that the PEFI harbors 22 native species of anurans, 24 native species of reptiles, and three exotic species of reptiles. Also, through surveying scientific collections, we found three species of amphibians and one of the snakes that were detected in the past but were not detected during our survey. The composition of amphibian species in the PEFI is similar to proximal small urban and periurban Atlantic Forest fragments, but its species richness is higher than these fragments even when compared to areas with similar or larger size. In conclusion, the highly urban PEFI supports considerable herpetofaunal diversity in comparison with other regional areas and our data reinforce the necessity of conserving this and other urban forest fragments through strategic management across the Atlantic Forest.

6.
J Biogeogr, v. 48, n.4, p. 823-832, dez. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3425

RESUMO

Aim Vicariance has often been invoked to explain bioregionalization patterns in the Neotropics. Using a revised point locality data for endemic species, we aimed to test for the first time the predictions of the vicariance model in shaping biogeographical regions for endemic snakes in the Atlantic Forest (AF) megadiverse hotspot. Location South American Atlantic Forest. Taxon Snakes (Reptilia, Serpentes). Methods To identify the non‐random groups of co‐distributed species, we mapped 21,101 point locality records in a grid cell of 0.5° × 0.5° across the AF, and constructed a presence–absence matrix of endemic species. The two major predictions of vicariance model were tested by Biotic Elements (BE) analysis, searching for groups of significantly co‐distributed species (Biotic Elements) by comparing distances between observed and artificial random ranges, produced under null models from Monte Carlo simulations. We also tested for the occurrence of sister species in different Biotic Elements, and compared our results with previous bioregionalization schemes revealed by other organisms in the AF. Results We recorded 252 species of snakes in the Atlantic Forest, of which 79 (31%) are endemic to this domain. Biotic Elements analysis with endemic species revealed seven clusters of co‐distributed species (BEs) corresponding to biogeographical regions. The significant non‐random clusters of geographical ranges revealed in BE analysis, and the distribution of sister species in different BEs, validated both central predictions of the vicariance model. Main conclusions Snakes defined non‐random biogeographical regions in the Atlantic Forest, and these were congruent with previously identified areas based on other groups of organisms, indicating that general processes influenced geographical ranges across the region. Both central predictions of the vicariance model were valid, indicating that vicariant events must have been important in shaping non‐random clusters of co‐distributed snakes in this biodiversity hotspot, harbouring some of the richest snake faunas on the planet.

7.
Ecography, v. 43, p. 328-339, fev. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3035

RESUMO

Factors driving the spatial configuration of centres of endemism have long been a topic of broad interest and debate. Due to different eco-evolutionary processes, these highly biodiverse areas may harbour different amounts of ancient and recently diverged organisms (paleo- and neo-endemism, respectively). Patterns of endemism still need to be measured at distinct phylogenetic levels for most clades and, consequently, little is known about the distribution, the age and the causes of such patterns. Here we tested for the presence of centres with high phylogenetic endemism (PE) in the highly diverse Neotropical snakes, testing the age of these patterns (paleo- or neo-endemism), and the presence of PE centres with distinct phylogenetic composition. We then tested whether PE is predicted by topography, by climate (seasonality, stability, buffering and relictualness), or biome size. We found that most areas of high PE for Neotropical snakes present a combination of both ancient and recently diverged diversity, which is distributed mostly in the Caribbean region, Central America, the Andes, the Atlantic Forest and on scattered highlands in central Brazil. Turnover of lineages is higher across Central America, resulting in more phylogenetically distinct PE centres compared to South America, which presents a more phylogenetically uniform snake fauna. Finally, we found that elevational range (topographic roughness) is the main predictor of PE, especially for paleo-endemism, whereas low paleo-endemism levels coincide with areas of high climatic seasonality. Our study highlights the importance of mountain systems to both ancient and recent narrowly distributed diversity. Mountains are both museums and cradles of snake diversity in the Neotropics, which has important implications for conservation in this region.

8.
South Am J Herpetol, v. 14, sp1, p. 1-274, dez. 2019
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2928

RESUMO

Accurate and detailed species distribution maps are fundamental for documenting and interpreting biological diversity. For snakes, an ecologically diverse group of reptiles, syntheses and detailed data on distribution patterns remain scarce. We present the first comprehensive collection of detailed, voucher-based, point-locality, range maps for all described and documented Brazilian snakes, with the major aim of mitigating the Wallacean shortfall and as a contribution towards a better understanding of this rich, threatened, and poorly studied megadiverse fauna. We recorded a total of 412 snake species in Brazil on the basis of an extensive and verified point-locality database of 163,498 entries and 75,681 unique records (available here as Online Supporting Information). Our results reveal previously undocumented patterns of distribution, sampling effort, richness, and endemism levels, resulting in a more objective view of snake diversity in the Neotropics. Apart from these achievements, we understand that the most relevant and enduring contribution of the present atlas is to stimulate researchers to publish corrections, additions, and new discoveries.

9.
Zootaxa, v. 4521, n. 4, p. 539-552, 2018
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2614

RESUMO

We describe a new species of the genus Apostolepis found near São Salvador Hydroelectric Power Plant, municipality of São Salvador do Tocantins, in the central Cerrado ecoregion. The new species is distinguished from its congeners by the following combination of characters: presence of eleven dorsolateral stripes, five infralabial scales and the lack of preoculars scales. The new species shares some external characteristics mainly with A. arenaria, A. gaboi and A. nelsonjorgei, with which it is compared.

10.
Biota neotrop. (Online, Ed. port.) ; 11(4): 67-81, Oct.-Dec. 2011. ilus, tab
Artigo em Português | LILACS-Express | LILACS | ID: lil-651612

RESUMO

Elaboramos uma lista das espécies de répteis do Estado de São Paulo com base nos registros confirmados de exemplares depositados nas três maiores coleções científicas do estado, complementando esta informação com a bibliografia disponível. Registramos a presença de 212 espécies de répteis no Estado de São Paulo, distribuídas em 23 famílias, incluindo 12 quelônios, três crocodilianos e 197 Squamata (142 serpentes, 44 "lagartos" e 11 anfisbenas). Destas, onze são endêmicas do Estado de São Paulo (Mesoclemmys cf. vanderhaegei, Amphisbaena sanctaeritae, Mabuya caissara, Mabuya macrorhyncha, Liotyphlops caissara, Liotyphlops schubarti, Corallus cropanii, Atractus serranus, Phalotris lativittatus, Bothropoides alcatraz, Bothropoides insularis). Entre os Squamata, quatro lagartos e uma serpente correspondem a espécies ainda não descritas. Destas 212 espécies, 32 estão incluídas na Lista das Espécies Ameaçadas do Estado de São Paulo, enquanto que apenas nove constam na Lista das Espécies Ameaçadas do Brasil. A riqueza de répteis atualmente registrada no Estado de São Paulo representa cerca de 30% da riqueza conhecida para o grupo em todo o território brasileiro, que abrange 721 espécies. Entretanto, concluímos que estudos mais detalhados sobre a taxonomia e a distribuição de espécies bem como os esforços de coleta em áreas com lacunas de amostragem devem ainda aumentar o número de espécies de répteis no estado.


The present study provides a list of species of reptiles known to occur in the State of São Paulo, based on specimens with confirmed localities, housed in the three largest scientific collections of the state, and published information. We registered the presence of 212 species of reptiles within the boundaries of the state that belong to 23 families and include 12 chelonians, three crocodilians, and 197 squamates (142 snakes, 44 "lizards," and 11 amphisbenians). Eleven species are endemic to the State of São Paulo (Mesoclemmys cf. vanderhaegei, Amphisbaena sanctaeritae, Mabuya caissara, Mabuya macrorhyncha, Liotyphlops caissara, Liotyphlops schubarti, Corallus cropanii, Atractus serranus, Phalotris lativittatus, Bothropoides alcatraz, Bothropoides insularis). Within Squamata, four lizards and one snake correspond to valid species that are still in need of formal description. Thirty-two species are included in the List of Threatened Species from the State of São Paulo, while only nine belong to the Brazilian List of Threatened Species. Reptile species richness for the state represents already approximately 30% of species richness known to occur in all the Brazilian territory, which includes 721 species. However, we conclude that more detailed taxonomic and distributional studies as well as more surveys targeting poorly known localities will have the effect of augmenting the number of species for the state.

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