Chromosomal rearrangements played an important role in the speciation of rice rats of genus Cerradomys (Rodentia, Sigmodontinae, Oryzomyini).

Rodents of the genus Cerradomys belong to tribe Oryzomyini, one of the most diverse and speciose groups in Sigmodontinae (Rodentia, Cricetidae). The speciation process in Cerradomys is associated with chromosomal rearrangements and biogeographic dynamics in South America during the Pleistocene era. As the morphological, molecular and karyotypic aspects of Myomorpha rodents do not evolve at the same rate, we strategically employed karyotypic characters for the construction of chromosomal phylogeny to investigate whether phylogenetic relationships using chromosomal data corroborate the radiation of Cerradomys taxa recovered by molecular phylogeny. Comparative chromosome painting using Hylaeamys megacephalus (HME) whole chromosome probes in C. langguthi (CLA), Cerradomys scotii (CSC), C. subflavus (CSU) and C. vivoi (CVI) shows that karyotypic variability is due to 16 fusion events, 2 fission events, 10 pericentric inversions and 1 centromeric repositioning, plus amplification of constitutive heterochromatin in the short arms of the X chromosomes of CSC and CLA. The chromosomal phylogeny obtained by Maximum Parsimony analysis retrieved Cerradomys as a monophyletic group with 97% support (bootstrap), with CSC as the sister to the other species, followed by a ramification into two clades (69% of branch support), the first comprising CLA and the other branch including CVI and CSU. We integrated the chromosome painting analysis of Eumuroida rodents investigated by HME and Mus musculus (MMU) probes and identified several syntenic blocks shared among representatives of Cricetidae and Muridae. The Cerradomys genus underwent an extensive karyotypic evolutionary process, with multiple rearrangements that shaped extant karyotypes. The chromosomal phylogeny corroborates the phylogenetic relationships proposed by molecular analysis and indicates that karyotypic diversity is associated with species radiation. Three syntenic blocks were identified as part of the ancestral Eumuroida karyotype (AEK): MMU 7/19 (AEK 1), MMU 14 (AEK 10) and MMU 12 (AEK 11). Besides, MMU 5/10 (HME 18/2/24) and MMU 8/13 (HME 22/5/11) should be considered as signatures for Cricetidae, while MMU 5/9/14, 5/7/19, 5 and 8/17 for Sigmodontinae.

Small mammals from the Caatinga: A dataset for the Brazilian semiarid biome.

The Caatinga is an exclusively Brazilian biome, and is the largest and most biodiverse Seasonal Tropical Dry Forest in the world. Despite that, the mammalian fauna, especially small mammals, is the least studied of all Brazilian biomes. In order to fill gaps and provide detailed information on small mammals (Didelphimorphia, Rodentia) in the Caatinga biome, we compiled reliable records focusing on richness, composition and some biometric data. These records came from mammal collections, papers, theses, books, and unpublished data, prioritizing records with vouchers housed in scientific collections. We compiled a total of 3133 records from 816 locations, resulting in a richness of 47 native species (12 marsupials and 35 rodents, plus three exotic rodents, Rattus rattus, Rattus norvegicus, and Mus musculus). This dataset includes records of three new species for the biome and its transition zone: the rodents Calomys mattevii, Holochilus oxe, and Nectomys squamipes. Of the total number of records, 1808 (57.71%) are from consulting activities, 95 (3.03%) are from zoonoses studies and 104 (3.32%) are from the National Plague Service (SNP). All nine Brazilian states with territory in the Caatinga have sampling data for small mammals, but the number of records and localities are unevenly distributed, with the state of Rio Grande do Norte having the lowest number of records and locations sampled. Our dataset is the first of its kind for the Caatinga biome and has considerable potential value for studies of habitat use, landscape ecology, macroecology, biogeography, and conservation. There are no copyright restrictions on the data. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

Estudo descritivo de casos notificados de febre maculosa em São Paulo, Rio de Janeiro e Minas Gerais entre 2007 e 2016 / Descriptive study of reported cases of spotted fever in São Paulo, Rio de Janeiro and Minas Gerais between 2007 and 2016

Resumo Introdução A febre maculosa é uma doença infecciosa aguda causada por bactérias do gênero Rickettsia e transmitida por carrapatos que pode levar à hospitalização e, eventualmente, a óbito por causa de quadros mais graves. Objetivo O objetivo deste artigo foi descrever o cenário epidemiológico da doença nas três unidades federativas de maior número de notificações e óbitos pela doença no Brasil entre 2007 e 2016. Método Estudo epidemiológico descritivo com base nos dados das fichas de investigação para a doença, sendo analisados dados demográficos, geográficos, ambientais e de hospitalização, diagnóstico e desfecho dos casos na área de estudo. Resultados Foram confirmados 953 casos da doença, em sua maioria por critérios laboratoriais, sendo observada maior prevalência entre homens com idade média de 35 anos, pouco relacionados ao ambiente de trabalho, mas amplamente relacionados ao meio urbano. Do total de casos confirmados, 64% pacientes afirmaram ter tido algum contato com carrapato, assim como com cães (36%), capivaras (20%) e equinos (19%). Conclusão Existem questionamentos a respeito da doença que não foram elucidados neste artigo, entretanto abordagens criativas, validadas e ancoradas na associação de áreas de conhecimento distintas poderão dar bons resultados se objetivamente aplicadas em ações estratégicas da gestão da saúde.

Abstract Background Spotted fever is an acute infectious disease caused by bacteria of the genus Rickettsia and transmitted by ticks, which can lead to hospitalization and, eventually, death due to more severe conditions. Objective The purpose of this article was to describe the epidemiological scenario of the disease in the three federal states with the highest number of notifications and deaths due to the disease in Brazil between 2007 and 2016. Method A descriptive epidemiological study was carried out based on data from the investigation forms for the disease, with data being analyzed on demographic, geographic, environmental, and hospitalization, diagnosis, and outcome of cases in the study area. Results 953 cases of the disease were confirmed, mostly by laboratory criteria, with a higher prevalence being observed among men with an average age of 35 years, little related to the work environment, but largely related to the urban environment. Of the total confirmed cases, 64% of patients said that they had had some contact with ticks, as well as with dogs (36%), capybaras (20%), and horses (19%). Conclusion We believe that there are questions about the disease that were not elucidated in this article, however, creative approaches, validated and anchored in the association of different areas of knowledge can give good results if objectively applied in strategic health management actions.

Updated list of non-volant small mammals from the Serra da Bocaina National Park, southeastern Brazil / Lista atualizada dos pequenos mamíferos não-voadores do Parque Nacional da Serra da Bocaina, sudeste do Brasil

Abstract In the core of the Atlantic Forest biome, the Serra da Bocaina National Park (SBNP) is located in the Atlantic Forest Southeast area of endemism for vertebrates. Filling gaps in knowledge about the spatial distribution and occurrence of species in national parks is of fundamental importance to know how many species are protected and to guide conservation initiatives. Here we updated the non-volant small mammal species list of the SBNP, providing new data on species list and abundance, with species identified mainly by karyotype and/or molecular analysis. Twelve sampling sessions with a capture-mark-recapture approach were carried out in four sites in the SBNP from 2013 to 2016, during the paving works of the state highway RJ-165 (Estrada Parque Paraty-Cunha), municipality of Paraty, state of Rio de Janeiro, Brazil. Non-volant small mammals (Rodentia and Didelphimorphia) were sampled using Sherman® and Tomahawk® live traps (18,987 trap-nights) and pitfall traps (4,591 trap-nights). Thirty-two species (11 marsupials and 21 rodents) were recorded from 1,185 captured specimens. Species richness ranged from 18 to 28 between sites. Ten and 11 species were exclusively captured in live traps and pitfall traps, respectively. The observed richness (32 species) represented 91.4% of the estimated species richness for the study area. Sites 2 and 4 were the most similar to each other regarding species composition, and site 3 was the most dissimilar. The species with highest relative abundance were Euryoryzomys russatus (14%) and Delomys dorsalis (14%), while six species had relative abundances lower than 1%. Fourteen and 17 species were identified by karyotype and molecular analysis, respectively. The present study added 22 species to the park's non-volant small mammals list, which now has 37 species with confirmed occurrence. This species richness found in the SBNP is one of the highest ever recorded for the group of non-volant small mammals in protected areas of the Atlantic Forest in Brazil, corroborating the Serra da Bocaina region as a biodiversity hotspot.

Resumen No cerne do bioma Mata Atlântica, o Parque Nacional da Serra da Bocaina (PNSB) está localizado na área Sudeste de endemismo para vertebrados na Mata Atlântica. Preencher lacunas de conhecimento sobre a distribuição espacial e ocorrência das espécies em parques nacionais é de fundamental importância para saber quantas espécies estão protegidas e orientar iniciativas de conservação. Aqui atualizamos a lista de espécies de pequenos mamíferos não-voadores do PNSB, fornecendo novos dados sobre a lista de espécies e abundância, com espécies identificadas principalmente por análises cariotípicas e/ou molecular. Doze sessões de amostragem com uma abordagem de captura-marcação-recaptura foram realizadas em quatro áreas no PNSB de 2013 a 2016, durante as obras de pavimentação da rodovia estadual RJ-165 (Estrada Parque Paraty-Cunha), município de Paraty, estado do Rio de Janeiro, Brasil. Os pequenos mamíferos não-voadores (Rodentia e Didelphimorphia) foram amostrados usando armadilhas de captura viva Sherman® e Tomahawk® (18.987 armadilhas-noite) e armadilhas de queda (4.591 armadilhas-noite). Trinta e duas espécies (11 marsupiais e 21 roedores) foram registradas em 1.185 espécimes capturados. A riqueza de espécies variou de 18 a 28 entre as áreas de amostragem. Dez e 11 espécies foram capturadas exclusivamente em armadilhas de captura viva e armadilhas de queda, respectivamente. A riqueza observada (32 espécies) representou 91,4% da riqueza de espécies estimada para a área de estudo. As áreas 2 e 4 foram as mais semelhantes entre si quanto à composição de espécies, e a área 3 foi a mais dissimilar. As espécies com maior abundância relativa foram Euryoryzomys russatus (14%) e Delomys dorsalis (14%), enquanto seis espécies tiveram abundâncias relativas inferiores a 1%. Quatorze e 17 espécies foram identificadas pelo cariótipo e por análise molecular, respectivamente. O presente estudo acrescentou 22 espécies à lista de pequenos mamíferos não-voadores do parque, que passou a contar com 37 espécies com ocorrência confirmada. Essa riqueza de espécies encontrada no PNSB é uma das maiores já registradas para o grupo dos pequenos mamíferos não-voadores em áreas protegidas da Mata Atlântica no Brasil, corroborando a região da Serra da Bocaina como um hotspot de biodiversidade.

Mapping potential risks for the transmission of spotted fever rickettsiosis: The case study from the Rio de Janeiro state, Brazil.

Spotted fever rickettsiosis is a zoonosis transmitted by ticks, having a varied clinical course that can lead to death if not managed properly. In Brazil it is more commonly observed in the Southeast, being an emerging public health problem. Hazard mapping models are common in different areas of knowledge, including public health, as a way of inferring reality and seeking to reduce or prevent damage. The aim of this study is to offer a spatial heuristic methodology for assessing the potential risk of transmission of spotted fever in the Rio de Janeiro state, located in the southeastern region of Brazil. For this, we used geospatial tools associated with eco-epidemiological data related to the clinical profile of the disease. The results achieved were substantially encouraging, considering that there are territories with greater or lesser expectation of risk for spotted fever in the study area. We observed that there are important distinctions between the two rickettsiosis scenarios in the same geographic space and that the areas where there is a greater potential risk of contracting rickettsiosis coincide with the administrative regions that concentrated the cases of hospitalization and deaths from the disease, concluding that the scenery found are relevant to the case series for the disease and that the planning of surveillance actions can gain in quality if the use of this spatial analysis tool is incorporated into the routine of local health management.

A new species of Akodon Meyen, 1833 (Rodentia: Cricetidae) from dry forests of the Amazonia-Cerrado transition.

Akodon is the most diverse genus of the tribe Akodontini, comprising 41 extant species. Although distributed in a wide range of environments in South America, the genus was long considered to be absent from Amazon Forest. Nonetheless, in recent decades, records of Akodon have been reported based on specimens from southern Amazonia, throughout the contact zone with Cerrado. Published data about the unique karyotype (2n=10), along with evidence of sister phylogenetic relationship (Cytb sequences) with Akodon cursor, a species from the Atlantic Forest, suggest that these specimens represent an undescribed species. Herein we hypothesize that these samples represent a new species of Akodon from Amazonia-Cerrado transitional areas. Through the analyses of 217 specimens from Mato Grosso and Pará states, Brazil, as well as 336 specimens of Akodon cursor species group from the Atlantic Forest, we provide qualitative and quantitative external and craniodental data that support their distinction in comparison with other congeners. The sister relationship between this new species and A. cursor provide additional evidence of a past connection between the two largest tropical forests of South America. Moreover, the recognition of Akodon n. sp. points to the presence of the genus in the Amazonia-Cerrado transition, an area currently under great anthropic pressure, highlighting the fact that we might be losing a portion of Brazilian biodiversity before even getting to know it.

Comparative genomic mapping reveals mechanisms of chromosome diversification in Rhipidomys species (Rodentia, Thomasomyini) and syntenic relationship between species of Sigmodontinae.

Rhipidomys (Sigmodontinae, Thomasomyini) has 25 recognized species, with a wide distribution ranging from eastern Panama to northern Argentina. Cytogenetic data has been described for 13 species with 12 of them having 2n = 44 with a high level of autosomal fundamental number (FN) variation, ranging from 46 to 80, assigned to pericentric inversions. The species are grouped in groups with low FN (46-52) and high FN (72-80). In this work the karyotypes of Rhipidomys emiliae (2n = 44, FN = 50) and Rhipidomys mastacalis (2n = 44, FN = 74), were studied by classical cytogenetics and by fluorescence in situ hybridization using telomeric and whole chromosome probes (chromosome painting) of Hylaeamys megacephalus (HME). Chromosome painting revealed homology between 36 segments of REM and 37 of RMA. We tested the hypothesis that pericentric inversions are the predominant chromosomal rearrangements responsible for karyotypic divergence between these species, as proposed in literature. Our results show that the genomic diversification between the karyotypes of the two species resulted from translocations, centromeric repositioning and pericentric inversions. The chromosomal evolution in Rhipidomys was associated with karyotypical orthoselection. The HME probes revealed that seven syntenic probably ancestral blocks for Sigmodontinae are present in Rhipidomys. An additional syntenic block described here is suggested as part of the subfamily ancestral karyotype. We also define five synapomorphies that can be used as chromosomal signatures for Rhipidomys.

Chromosomal Signatures Corroborate the Phylogenetic Relationships within Akodontini (Rodentia, Sigmodontinae).

Comparative chromosome-painting analysis among highly rearranged karyotypes of Sigmodontinae rodents (Rodentia, Cricetidae) detects conserved syntenic blocks, which are proposed as chromosomal signatures and can be used as phylogenetic markers. In the Akodontini tribe, the molecular topology (Cytb and/or IRBP) shows five low-supported clades (divisions: "Akodon", "Bibimys", "Blarinomys", "Oxymycterus", and "Scapteromys") within two high-supported major clades (clade A: "Akodon", "Bibimys", and "Oxymycterus"; clade B: "Blarinomys" and "Scapteromys"). Here, we examine the chromosomal signatures of the Akodontini tribe by using Hylaeamys megacephalus (HME) probes to study the karyotypes of Oxymycterus amazonicus (2n = 54, FN = 64) and Blarinomys breviceps (2n = 28, FN = 50), and compare these data with those from other taxa investigated using the same set of probes. We strategically employ the chromosomal signatures to elucidate phylogenetic relationships among the Akodontini. When we follow the evolution of chromosomal signature states, we find that the cytogenetic data corroborate the current molecular relationships in clade A nodes. We discuss the distinct events that caused karyotypic variability in the Oxymycterus and Blarinomys genera. In addition, we propose that Blarinomys may constitute a species complex, and that the taxonomy should be revised to better delimit the geographical boundaries and their taxonomic status.

DNA barcoding of the rodent genus Oligoryzomys (Cricetidae: Sigmodontinae): mitogenomic-anchored database and identification of nuclear mitochondrial translocations (Numts).

DNA barcoding has become a standard method for species identification in taxonomically complex groups. An important step of the barcoding process is the construction of a library of voucher-based material that was properly identified by independent methods, free of inaccurate identification, and paralogs. We provide here a cytochrome oxidase I (mt-Co1) DNA barcode database for species of the genus Oligoryzomys, based on type material and karyotyped specimens, and anchored on the mitochondrial genome of one species of Oligoryzomys, O. stramineus. To evaluate the taxonomic determination of new COI sequences, we assessed species intra/interspecific genetic distances (barcode gap), performed the General Mixed Yule Coalescent method (GMYC) for lineages' delimitation, and identified diagnostic nucleotides for each species of Oligoryzomys. Phylogenetic analyses of Oligoryzomys were performed on 2 datasets including 14 of the 23 recognized species of this genus: a mt-Co1 only matrix, and a concatenated matrix including mt-Co1, cytochrome b (mt-Cytb), and intron 7 of the nuclear fibrinogen beta chain gene (i7Fgb). We recovered nuclear-mitochondrial translocated (Numts) pseudogenes on our samples and identified several published sequences that are cases of Numts. We analyzed the rate of non-synonymous and synonymous substitution, which were higher in Numts in comparison to mtDNA sequences. GMYC delimitations and DNA barcode gap results highlight the need for further work that integrate molecular, karyotypic, and morphological analyses, as well as additional sampling, to tackle persistent problems in the taxonomy of Oligoryzomys.

Abundance of small mammals in the Atlantic Forest (ASMAF): a data set for analyzing tropical community patterns.

Local abundance results from the interaction between populational and environmental processes. The abundance of the species in a community is also one of the most basic descriptors of its structure. Despite its importance, information about species abundances is fragmentary, creating a knowledge gap about species abundances known as the Prestonian Shortfall. Here we present a comprehensive data set of small mammal abundance in the Atlantic Forest. Data were extracted from 114 published sources and from unpublished data collected by our research groups spanning from 1943 to 2017. The data set includes 1,902 records of at least 111 species in 155 localities, totaling 42,617 individuals represented. We selected studies that (1) were conducted in forested habitats of the Atlantic Forest, (2) had a minimum sampling effort of at least 500 trap-nights, and (3) contained species abundance data in detail. For each study, we recorded (1) latitude and longitude, (2) name of the locality, (3) employed sampling effort, (4) type of traps used, (5) study year, (6) country, and (7) species name with (8) its respective abundances. For every locality, we also obtained information regarding its (9) ecoregion, (10) predominant vegetation type, and (11) biogeographic subdivision. Whenever necessary, we also (12) updated the species names as new species were described and some genera suffered taxonomic revision since the publication. The localities are spread across the Atlantic Forest and most of the small mammal species known to occur in Atlantic Forest are present in the data set, making it representative of communities of the entire biome. This data set can be used to address various patterns in community ecology and geographical ecology, as the relation between local abundance and environmental suitability, hypothesis regarding local and regional factors on community structuring, species abundance distributions (SAD), functional and phylogenetic mechanisms on community assembling.

Oecomys catherinae (Sigmodontinae, Cricetidae): Evidence for chromosomal speciation?

Among the Oryzomyini (Sigmodontinae), Oecomys is the most speciose, with 17 species. This genus presents high karyotypic diversity (2n = 54 to 2n = 86) and many taxonomic issues at the species level because of the presence of cryptic species and the overlap of morphological characters. For these reasons the real number of species of Oecomys may be underestimated. With the aim of verifying if the taxon Oecomys catherinae is composed of more than one species, we made comparative studies on two populations from two regions of Brazil, one from the Amazon and another from the Atlantic Forest using both classical cytogenetics (G- and C-banding) and comparative genomic mapping with whole chromosome probes of Hylaeamys megacephalus (HME), molecular data (cytochrome b mitochondrial DNA) and morphology. Our results confirm that Oecomys catherinae occurs in the southeast Amazon, and reveal a new karyotype for the species (2n = 62, FNa = 62). The comparative genomic analysis with HME probes identified chromosomal homeologies between both populations and rearrangements that are responsible for the different karyotypes. We compared our results in Sigmodontinae genera with other studies that also used HME probes. These chromosomal differences together with the absence of consistent differentiation between the two populations on morphological and molecular analyses suggest that these populations may represent cryptic species.

Karyotype of three Lonchophylla species (Chiroptera, Phyllostomidae) from Southeastern Brazil.

Lonchophylla Thomas, 1903 is a Neotropical bat genus that comprises 12 species, with little cytogenetic information available. Here we present the description of the karyotype of three species collected in Southeastern Brazil. Lonchophylla bokermanni Sazima, Vizotto & Taddei, 1978, Lonchophylla dekeyseri Taddei, Vizotto & Sazima, 1983, and Lonchophylla peracchii Dias, Moratelli & Esberard, 2013 showed the same diploid number 2n = 28 and the same autosomal fundamental number FNa = 50, in both Lonchophylla bokermanni and Lonchophylla peracchii. We observed that the karyotypes were also cytogenetically similar when we compared the studied species with other species within the same genus. It is therefore not possible to differentiate the species using only karyotypes with conventional staining. However, this information increases the knowledge of the genus and can be one more important character for a better phylogenetic comprehension of this taxon.

Distribution of Oecomys catherinae Thomas, 1909 (Rodentia: Cricetidae) in northeastern Brazil with karyotypical and morphometrical notes / Distribuição de Oecomys catherinae Thomas, 1909 (Rodentia: Cricetidae) no nordeste do Brasil com notas morfométricas e cariotípicas

The genus Oecomys Thomas, 1906 is currently composed of 16 species with unclear taxonomy and poorly known geographic limits. O. catherinae Thomas, 1909 is known to occur within the Brazilian Atlantic Forest from the states of Santa Catarina to Pernambuco (where the northernmost previously known specimen of Oecomys in the Atlantic forest was recorded), and along riverine forest into the Cerrado. To gain a greater understanding of its geographical and ecological distribution (mainly in Northeastern Brazil) and of its taxonomic characterization, we provide a short review of karyotypical and morphometrical data from specimens collected within the distribution range of the species. Specimens presented 2n = 60 and AN varying between 62 and 64. A table with external and cranial measurements of the analyzed specimens is provided. In this paper we also report the presence of O. catherinae in the semi-deciduous forests of the state of Paraíba, representing the northernmost records of the species in the Atlantic forest and thereby extending its known geographical limits.

Oecomys Thomas, 1906 é um gênero atualmente composto por 16 espécies reconhecidas que apresentam taxonomia e distribuições geográficas ainda incertas. O. catherinae Thomas, 1906 é a espécie que ocorre ao longo da Floresta Atlântica brasileira dos estados de Santa Catarina a Pernambuco, onde se encontra o registro prévio mais ao norte para Oecomys na Floresta Atlântica, e ao longo de florestas de galeria no Cerrado. Pretendendo esclarecer aspectos relacionados à distribuição geográfica e ecológica de O. catherinae, com ênfase na região nordeste do Brasil, e auxiliar na sua caracterização taxonômica, fornecemos um breve resumo de dados morfométricos e cariotípicos de indivíduos coletados em diversos trabalhos ao longo da área de ocorrência da espécie. Os espécimens apresentaram 2n = 60 e NA variando entre 62 e 64. Uma tabela de medidas corporais externas e cranianas dos indivíduos analisados é fornecida. Também registramos pela primeira vez a presença de O. catherinae nas florestas semi-deciduais do estado da Paraíba, sendo atualmente os registros mais ao norte da espécie na Floresta Atlântica, estendendo os limites geográficos conhecidos para a espécie.

Colonization process of the Brazilian common vesper mouse, Calomys expulsus (Cricetidae, Sigmodontinae): a biogeographic hypothesis.

Riverine barriers have been associated to genetic diversification and speciation of several taxa. The Rio São Francisco is one of the largest rivers in South America, representing the third largest river basin in Brazil and operating as a geographic barrier to gene flow of different taxa. To evaluate the influence of the Rio São Francisco in the speciation of small rodents, we investigated the genetic structure of Calomys expulsus with phylogenetic and network analyses of cytochrome b DNA. Our results suggested that C. expulsus can be divided into 3 subpopulations, 2 on the left and another one on the right bank of this river. The time of divergence of these subpopulations, using a Bayesian framework, suggested colonization from the south to the north/northeast. Spatial analysis using a clustering method and the Monmonier's algorithm suggested that the Rio São Francisco is a biogeographic barrier to gene flow and indicated that this river may play a role in the incipient speciation process of these subpopulations.

Distribution extension and sympatric occurrence of Gracilinanus agilis and G. microtarsus (Didelphimorphia, Didelphidae), with cytogenetic notes / Extensão da distribuição e ocorrência em simpatria de Gracilinanus agilis e G. microtarsus (Didelphimorphia, Didelphidae) com notas citogenéticas

Gracilinanus microtarsus, from the Atlantic Forest and G. agilis, widespread in central Brazil in the Cerrado and in the northeastern Caatinga are two small Neotropical arboreal opossum species not frequently recorded in simpatry. Here we report eight G. agilis specimens from three localities and 17 G. microtarsus, from 10 localities, all in Minas Gerais, Rio de Janeiro and Bahia states. Species proper identification followed diagnostic characters as appearance of dorsum pelage, ocular-mark, ears and tail lengths and size proportion of the posteromedial vacuities in cranium. Chromosomes in metaphases of five specimens were obtained for both species. Our records extend the previous known geographical distribution of G. microtarsus to Chapada Diamantina, in Bahia State and report the occurrence of both species in simpatry. G. microtarsus, in coastal area, was captured in dense ombrophilous and in semideciduous forests, in deciduous seasonal forest and Cerradão in Chapada Diamantina. G. agilis was recorded in gallery forests of Cerrado and very green and dense bush formation of Caatinga. Autosomal complement showed the same diploid and autosomal number already described for both species (2n = 14, NA = 24). Measurements are according to those given in literature and pelage characteristics were useful for the correct species identification. Here we report both G. agilis, described to be endemic to the Cerrado/Caatinga, in opposite to G. microtarsus, considered to be endemic to Atlantic Forest occurring in simpatry in two localities of the Cerrado. Such results indicates that long term trapping effort are necessary to a better definition of species taxonomy, distribution patterns along time and comprehensive understanding how anthropic environmental changes can be interfering in their evolutionary history.

Gracilinanus microtarsus, da Mata Atlântica e G. agilis, amplamente distribuído no Brasil central, tanto no Cerrado como na Caatinga são duas pequenas espécies de cuícas arbóreas. As duas espécies são raramente registradas em simpatria. Aqui registramos oito espécimes de G. agilis coletadas em três localidades e 17 G. microtarsus, de dez localidades, todas nos estados de Minas Gerais, Rio de Janeiro e Bahia. A correta identificação baseou-se nos caracteres diagnósticos como aparência da pelagem dorsal, marca escura na região óptica, comprimentos da orelha e cauda, bem como a proporção do tamanho das vacuidades posteromediais do crânio. Cromossomos metafásicos de cinco indivíduos foram obtidos. Nossos registros aumentam a distribuição geográfica previamente conhecida de G. microtarsus para a Chapada Diamantina, no estado da Bahia, e reporta a ocorrência de simpatria. G. microtarsus, na área costeira, foi capturado em florestas ombrófila densa e semidecidual em floresta estacional decidual e Cerradão na Chapada Diamantina. G. agilis foi registrado em matas de galeria do Cerrado, e formações densas de vegetação arbustiva verde na Caatinga. O complemento autossômico mostrou os mesmos números diplóides e autossômicos já registrados para as duas espécies (2n = 14, NA = 24). Medidas corpóreas estão de acordo com a literatura, e as características de pelagem foram ferramentas úteis para a correta identificação das espécies. Aqui registramos G. agilis, descrita como sendo uma espécie endêmica do Cerrado e da Caatinga, em oposição a G. microtarsus, considerada como endêmica da Mata Atlântica ocorrendo em simpatria em duas localidades do Cerrado. Tais resultados indicam que esforços continuados de coleta são necessários para uma melhor definição da taxonomia das espécies, dos padrões de distribuição ao longo do tempo e uma melhor compreensão de como as mudanças ambientais antrópicas estão interferindo em suas historias evolutivas.

Non-flying mammals of Chapada Diamantina (Bahia, Brazil) / Mamíferos não-voadores da Chapada Diamantina (Bahia, Brasil)

Chapada Diamantina is located in central Bahia state, and has a large diversity of habitats, including important transitional areas, but has remained largely unstudied until now. In the present study we list the non-flying mammals of Chapada Diamantina National Park and surroundings. We captured only small non-volant mammals, medium and large mammals were assessed through indirect evidences (tracks and marks) and interviews. We recorded 58 species and 47 genera from seven Mammalian orders. Seven species are included in the list of endangered Brazilian species by IBAMA and IUCN; and other seven are classified as data-deficient. Species richness of small mammals was equivalent among sampled habitats, but species composition varied among habitats (10 in semi-deciduous forest, 9 in rocky savanna and 8 in cerrado sensu stricto), as some species are restricted by humidity to forest habitats. During four different samplings, eight species were collected only in open vegetation, four only in forests, and six in both habitats. Oligoryzomys rupestris and Gracilinanus microtarsus had its geographic range expanded. Faunal composition is similar to the one observed in the Atlantic Forest, including species from Cerrado and Caatinga. Besides, some species occupy different habitats from those previously ascribed to them.

A Chapada Diamantina está localizada na parte central do Estado da Bahia, apresentando grande diversidade de habitats, assim como áreas de transição. Seu isolamento da Mata Atlântica costeira por extensa área de vegetação aberta fazem com que seja uma região de particular interesse na compreensão dos padrões de ocorrência e evolução da mastofauna neotropical. Uma lista de mamíferos não voadores do Parque Nacional da Chapada Diamantina e arredores foi elaborada. O esforço de captura foi realizado apenas para pequenos mamíferos, assim, a sua composição e riqueza de espécies entre habitats (floresta decidual, cerrado sensu stricto e campo rupestre) foram calculadas. Visitas às coleções científicas permitiram, junto com os dados de coletas, a compilação de 58 espécies e 47 gêneros de sete ordens de mamíferos. Sete espécies estão incluídas nas listas de espécies brasileiras ameaçadas de extinção do IBAMA e do IUCN; e outras sete estão classificadas como espécies com pouco conhecimento. A riqueza de espécies de pequenos mamíferos foi equivalente entre os habitats sem relação com o esforço amostral e número de espécies coletadas (10 na floresta decidual, nove em campo rupestre e oito no cerrado sentido restrito). A composição de espécies de pequenos mamíferos variou entre habitats, já que algumas espécies são restritas a ambientes úmidos e com fitosionomia florestal. Durante os quatro períodos de captura foi observada uma maior afinidade de algumas espécies em relação ao tipo de vegetação: oito ocorreram apenas em vegetação aberta, quatro apenas em floresta e seis espécies nos dois tipos de habitats. Oligoryzomys rupestris e Gracilinanus microtarsus tiveram sua distribuição geográfica expandida. A composição faunística apresenta afinidades com a Mata Atlântica com a influência do Cerrado e da Caatinga, com algumas espécies ocupando habitats diferentes daqueles previamente registrados.