RESUMEN
Blarinomys breviceps possesses cryptic and burrowing habits with poorly documented genetics and life history traits. Due to its rarity, only a few specimens and DNA sequences have been deposited in collections worldwide. Here, we present the most comprehensive cytogenetic and molecular characterization of this rare genus. Phylogenetic analyses based on partial cytochrome b sequences were performed, attempting to establish the relationships among individuals with distinct karyotypes along the geographic distribution of the genus in the Atlantic Forest. Classical and molecular cytogenetics, using banding patterns and FISH of telomeric and whole chromosome X-specific painting probes (obtained from the Akodontini Akodon cursor) were used to characterize and compare the chromosomal complements. Molecular phylogenetic analyses recovered 2 main geographically structured clades, northeastern and southeastern with pairwise sequence divergences among specimens varying between 4.9 and 8.4%. Eight distinct karyomorphs are described: (A) 2n = 52 (50A, XX), (B) 2n = 52 (48A, XY+2Bs), (C) 2n = 45 (42A, XY+1B), (D) 2n = 43 (37A, XX+4Bs), (E) 2n = 37 (34A, XY+1B), (F) 2n = 34 (32A, XX), (G) 2n = 31 (27A, XX+2Bs), (H) 2n = 28 (26A, XY), all with the same number of autosomal arms (FN(A) = 50). Variation of 0-4 supernumerary chromosomes (Bs) presenting heterogeneity in morphology and distribution of interstitial telomeric sequences (ITSs) is reported. ITSs are also found in some metacentric autosomes. The phylogeographic separation between 2 major lineages with high levels of genetic divergence, and the wide karyotypic diversity indicate that B. breviceps is a diverse group that warrants taxonomic re-evaluation.
Asunto(s)
Filogenia , Sigmodontinae/genética , Animales , Brasil , Cariotipificación , FilogeografíaRESUMEN
The Chapada Diamantina (CD) is located in Bahia State, between 11-14 degrees S and 41-43 degrees W, being part of the Serra do Espinhaço. The occurrence of different habitats and transition areas permits an interesting mammal fauna composition, with species from different biomes living in sympatry. Species of Didelphimorphia and Rodentia are important members of mammal communities in almost all different habitats, and morphological and cytogenetic characters are important for a correct identification of most of these species. In this work 258 specimens of small mammals from the orders Didelphimorphia (six genera and six species) and Rodentia (two families, five Sigmodontinae tribes, nine genera and 11 species) were collected during the whole field work (44 nights with traps). Chromosome preparations were obtained from 145 specimens from the species: Marmosops incanus, Gracilinanus microtarsus, Monodelphis domestica, Akodon aff. cursor, Necromys lasiurus, Cerradomys sp., Oligoryzomys fornesi, O. nigripes, O. rupestris, Calomys expulsus, Rhipidomys macrurus, Wiedomys pyrrhorhinus and Thrichomys inermis. Didelphis albiventris, Micoureus demerarae, Thylamys karymii and Nectomys sp. were identified by morphological characters. Most analyzed specimens do not show karyotype variation. However, numerical chromosomic variation was found in two individuals of Akodon aff. cursor (2n = 15) and in one individual of Cerradomys sp. (2n = 51). Structural variation in karyotype was observed in seven individuals of Cerradomys sp., showing one additional pair of metacentric chromosomes.
Asunto(s)
Marsupiales/genética , Roedores/genética , Animales , Brasil , Femenino , Cariotipificación , Masculino , Marsupiales/clasificación , Roedores/clasificaciónRESUMEN
Itatiaia National Park (PNI) and its surroundings present a unique fauna due to different forest formations with well-defined climatic and vegetation bands. The Itatiaia massif has four vegetation types that follow an altitudinal gradient: lower montane forest, montane forest, upper montane forest, and Campos de Altitude. Hence, this region is ideal for studying geographical variation in biological diversity. The main objectives of this study were to report on nonvolant mammal species known to occur in Itatiaia National Park and its surroundings and to determine if their distributional pattern is related to elevation. A review of the literature and a complete survey of specimens deposited in museums, as well as small-mammal trapping were carried out in order to obtain a complete record of the species from the region. Precise locality data were obtained for all specimens recorded, allowing the inclusion of each collected or observed individual in an altitude and vegetational class. We made a direct ordination gradient of marsupial, primate, and rodent species abundance with the altitude. Sixty-nine mammal species were collected or reported for the Itatiaia massif, belonging to seven orders and 20 families. Of these, 33 species (47.8%) are included in the official list of threatened or believed-to-be threatened species in Rio de Janeiro State. The orders Rodentia, Carnivora, and Didelphimorphia had the highest species richness, with 25, 14, and 13 species respectively. When species were grouped according to the vegetation, 16 species occured in the lower montane, 56 in the montane forest, five in the upper montane, and 21 in the high-altitude fields (Campos de Altitude). The communities of marsupials, primates, and rodents have an ordination pattern related to the altitude. Species richness was higher between 500 m and 1,500 m above sea level in montane forest, which is in agreement with recent studies showing that species richness can reach its maximum at mid-elevations.
Asunto(s)
Altitud , Biodiversidad , Mamíferos/clasificación , Árboles , Animales , Brasil , Densidad de Población , Dinámica PoblacionalRESUMEN
Ecological aspects related to parasitism are one of the less studied issues in parasitology research, and the scarce evidence available supports that younger specimens present higher infestation rates. The purpose of this work is to establish if higher infestation rates are observed in nursing females and their young captured inside their roost. Bats were captured inside a shelter located in RPPN Estação Veracel, Santa Cruz de Cabrália, Bahia state, Brazil. A total of 56 individuals of Carollia perspicillata were observed, 17 captured inside the roost during the day and 39 in trails at night. Captures of C. perspicillata during the day in a shelter yielded similar infestation rates to bats netted in trails and higher prevalence. The hypothesis that young were more infected was confirmed, based on the higher infestation of nursing females with neonates and on the significant inverse relation between body weight and number of parasites in young and subadults.
Asunto(s)
Quirópteros/parasitología , Dípteros , Infestaciones Ectoparasitarias/veterinaria , Animales , Animales Recién Nacidos , Brasil/epidemiología , Quirópteros/clasificación , Infestaciones Ectoparasitarias/epidemiología , Femenino , Interacciones Huésped-Parásitos , Vivienda para Animales , Masculino , Embarazo , PrevalenciaRESUMEN
Ecological aspects related to parasitism are one of the less studied issues in parasitology research, and the scarce evidence available supports that younger specimens present higher infestation rates. The purpose of this work is to establish if higher infestation rates are observed in nursing females and their young captured inside their roost. Bats were captured inside a shelter located in RPPN Estação Veracel, Santa Cruz de Cabrália, Bahia state, Brazil. A total of 56 individuals of Carollia perspicillata were observed, 17 captured inside the roost during the day and 39 in trails at night. Captures of C. perspicillata during the day in a shelter yielded similar infestation rates to bats netted in trails and higher prevalence. The hypothesis that young were more infected was confirmed, based on the higher infestation of nursing females with neonates and on the significant inverse relation between body weight and number of parasites in young and subadults.
Aspectos ecológicos relacionados ao parasitismo são uma das questões menos estudadas em parasitologia e poucas evidências sobre indivíduos jovens apresentando maiores taxas de infestações estão disponíveis.O objetivo deste trabalho é estabelecer se a taxa de infestação mais elevada é observada em fêmeas lactantes e jovens capturados dentro de seu refúgio. Os morcegos foram capturados dentro de um abrigo localizado na RPPN EstaçãoVeracel, Santa Cruz deCabrália-Bahia, Brasil. Um total de 56 indivíduos de Carollia perspicillata foi observado, sendo que 17 indivíduos foram capturados dentro do refúgio, durante o dia, e 39 foram capturados em trilhas, à noite. Indivíduos de C. perspicillata capturados durante o dia no abrigo apresentaram índices de infestação semelhantes aos morcegos capturados em trilhas e maior prevalência. A hipótese de que jovens eram maisinfectados foi confirmada, com base na maior infestação de fêmeas com recém-nascidos e na relação inversa significativa entre o peso corporal e o número de parasitas em jovens e subadultos.
Asunto(s)
Animales , Femenino , Masculino , Embarazo , Quirópteros/parasitología , Dípteros , Infestaciones Ectoparasitarias/veterinaria , Animales Recién Nacidos , Brasil/epidemiología , Quirópteros/clasificación , Infestaciones Ectoparasitarias/epidemiología , Interacciones Huésped-Parásitos , Vivienda para Animales , PrevalenciaRESUMEN
Karyotypic comparisons among five Akodon species showed that they shared a substantial proportion of their chromosome complements, indicated by distinct homologies between chromosomes, arms, or arm regions despite that this genus is karyotypically rearranged. A comparison with a related outgroup (Bolomys lasiurus) allowed for the recognition of ancestral and derived karyotypic traits as well as for inferring the direction of several chromosome rearrangements. This study indicated that species with lower diploid chromosome number are derived from species with higher diploid number, mainly by 11 fusions and 1 pericentric inversion while the direction of 5 other rearrangements could not be determined (fusions or fissions). UPGMA analyses of karyologic data indicated a topology like (Bolomys lasiurus (Akodon sp. (A. lindberghi (A. montensis (A. aff. cursor, A. cursor))))).
Asunto(s)
Cariotipificación , Filogenia , Roedores/genética , Animales , Células de la Médula Ósea/citología , Brasil , Células Cultivadas , Bandeo Cromosómico , Femenino , Reordenamiento Génico , Geografía , Masculino , Roedores/clasificaciónRESUMEN
The Chapada Diamantina (CD) is located in Bahia State, between 11-14° S and 41-43° W, being part of the Serra do Espinhaço. The occurrence of different habitats and transition areas permits an interesting mammal fauna composition, with species from different biomes living in sympatry. Species of Didelphimorphia and Rodentia are important members of mammal communities in almost all different habitats, and morphological and cytogenetic characters are important for a correct identification of most of these species. In this work 258 specimens of small mammals from the orders Didelphimorphia (six genera and six species) and Rodentia (two families, five Sigmodontinae tribes, nine genera and 11 species) were collected during the whole field work (44 nights with traps). Chromosome preparations were obtained from 145 specimens from the species: Marmosops incanus, Gracilinanus microtarsus, Monodelphis domestica, Akodon aff. cursor, Necromys lasiurus, Cerradomys sp., Oligoryzomys fornesi, O. nigripes, O. rupestris, Calomys expulsus, Rhipidomys macrurus, Wiedomys pyrrhorhinus and Thrichomys inermis. Didelphis albiventris, Micoureus demerarae, Thylamys karymii and Nectomys sp. were identified by morphological characters. Most analyzed specimens do not show karyotype variation. However, numerical chromosomic variation was found in two individuals of Akodon aff. cursor (2n = 15) and in one individual of Cerradomys sp. (2n = 51). Structural variation in karyotype was observed in seven individuals of Cerradomys sp., showing one additional pair of metacentric chromosomes.
A Chapada Diamantina (CD) está localizada no estado da Bahia entre as coordenadas 11°-14° S e 41°-43° W, fazendo parte da Serra do Espinhaço. A ocorrência de diferentes hábitats e áreas de transição levam a uma composição da mastofauna interessante, podendo ser encontradas espécies de diferentes biomas convivendo em simpatria. As espécies das ordens Didelphimorphia e Rodentia compreendem membros importantes nas comunidades de mamíferos, praticamente em todos os diferentes habitats, e as características morfológicas e citogenéticas são importantes para a correta identificação da maioria das espécies. Neste trabalho, 258 espécimes de pequenos mamíferos das ordens Didelphimorphia (seis gêneros e seis espécies) e Rodentia (duas famílias, cinco tribos Sigmodontinae, nove gêneros e onze espécies) foram coletados durante todo o trabalho de campo (44 noites de armadilhamento). As preparações cromossômicas foram obtidas em 145 indivíduos dentre as seguintes espécies: Marmosops incanus, Gracilinanus microtarsus, Monodelphis domestica, Akodon aff. cursor, Necromys lasiurus, Cerradomys sp., Oligoryzomys fornesi, O. nigripes, O. rupestris, Calomys expulsus, Rhipidomys macrurus, Wiedomys pyrrhorhinus e Thrichomys inermis. Didelphis albiventris, Micoureus demerarae, Thylamys karymii e Nectomys sp. foram identificadas por análises morfológicas. A maioria dos indivíduos coletados não apresentou variação cariotípica. Porém, variação cromossômica numérica foi encontrada em dois espécimes de Akodon aff. cursor (2n = 15) e em um indivíduo de Cerradomys sp. (2n = 51). Foi também observada variação estrutural no cariótipo de sete indivíduos de Cerradomys sp., mostrando um par a mais de cromossomos metacêntricos.
Asunto(s)
Animales , Femenino , Masculino , Marsupiales/genética , Roedores/genética , Brasil , Cariotipificación , Marsupiales/clasificación , Roedores/clasificaciónRESUMEN
Itatiaia National Park (PNI) and its surroundings present a unique fauna due to different forest formations with well-defined climatic and vegetation bands. The Itatiaia massif has four vegetation types that follow an altitudinal gradient: lower montane forest, montane forest, upper montane forest, and Campos de Altitude. Hence, this region is ideal for studying geographical variation in biological diversity. The main objectives of this study were to report on nonvolant mammal species known to occur in Itatiaia National Park and its surroundings and to determine if their distributional pattern is related to elevation. A review of the literature and a complete survey of specimens deposited in museums, as well as small-mammal trapping were carried out in order to obtain a complete record of the species from the region. Precise locality data were obtained for all specimens recorded, allowing the inclusion of each collected or observed individual in an altitude and vegetational class. We made a direct ordination gradient of marsupial, primate, and rodent species abundance with the altitude. Sixty-nine mammal species were collected or reported for the Itatiaia massif, belonging to seven orders and 20 families. Of these, 33 species (47.8%) are included in the official list of threatened or believed-to-be threatened species in Rio de Janeiro State. The orders Rodentia, Carnivora, and Didelphimorphia had the highest species richness, with 25, 14, and 13 species respectively. When species were grouped according to the vegetation, 16 species occured in the lower montane, 56 in the montane forest, five in the upper montane, and 21 in the high-altitude fields (Campos de Altitude). The communities of marsupials, primates, and rodents have an ordination pattern related to the altitude. Species richness was higher between 500 m and 1,500 m above sea level in montane forest, which is in agreement with recent studies showing that species richness can reach its maximum at mid-elevations.
O Parque Nacional do Itatiaia e seu entorno apresenta fauna peculiar em razão de diferentes formações vegetais, consistindo em faixas definidas de clima e de vegetação. O maciço do Itatiaia tem quatro tipos de vegetação que seguem um gradiente altitudinal: Floresta Submontana, Floresta Montana, Floresta Alto-Montana e Campos de Altitude. Por isso, essa região é ideal para estudar variação geográfica na diversidade biológica. O principal objetivo deste estudo foi relatar as espécies de mamíferos não-voadores conhecidas para o Parque Nacional do Itatiaia e seu entorno e determinar se elas apresentam padrão de distribuição altitudinal. Foram realizados revisão completa da literatura e levantamento de espécimes depositados em museus, bem como esforços de captura de pequenos mamíferos, a fim de obter o levantamento completo das espécies da região. Dados precisos sobre as localidades foram obtidos para todos os espécimes levantados, permitindo a colocação de cada indivíduo coletado ou observado dentro de uma classe de altitude e de vegetação. Foi elaborado gradiente de ordenação direto da abundância de espécies de marsupial, de primatas e de roedores com a altitude. Foram coletadas ou relatadas 69 espécies de mamíferos para o maciço do Itatiaia, pertencendo a 7 ordens e 20 famílias. Dessas, 33 espécies (47,8%) estão incluídas na lista oficial de espécies ameaçadas de extinção, ou presumivelmente ameaçadas, do Estado do Rio de Janeiro. As ordens Rodentia, Carnivora e Didelphimorphia apresentaram as mais altas riquezas de espécies, com 25, 14 e 13 espécies, respectivamente. Quando agrupadas de acordo com a vegetação, 16 espécies ocorreram na Floresta Submontana, 56 ocorreram na Floresta Montana, 5, na Floresta Alto-Montana e 21, nos Campos de Altitude. As comunidades de marsupiais, primatas e roedores têm padrão de ordenação relacionado com a altitude. A riqueza de espécies foi maior entre 500 m e 1.500 m, na Floresta Montana, o que está de acordo com estudos recentes que mostram que a riqueza de espécies alcança seu valor máximo em elevações medianas.
RESUMEN
O Parque Nacional do Itatiaia e seu entorno apresenta fauna peculiar em razão de diferentes formações vegetais, consistindo em faixas definidas de clima e de vegetação. O maciço do Itatiaia tem quatro tipos de vegetação que seguem um gradiente altitudinal: Floresta Submontana, Floresta Montana, Floresta Alto-Montana e Campos de Altitude. Por isso, essa região é ideal para estudar variação geográfica na diversidade biológica. O principal objetivo deste estudo foi relatar as espécies de mamíferos não-voadores conhecidas para o Parque Nacional do Itatiaia e seu entorno e determinar se elas apresentam padrão de distribuição altitudinal. Foram realizados revisão completa da literatura e levantamento de espécimes depositados em museus, bem como esforços de captura de pequenos mamíferos, a fim de obter o levantamento completo das espécies da região. Dados precisos sobre as localidades foram obtidos para todos os espécimes levantados, permitindo a colocação de cada indivíduo coletado ou observado dentro de uma classe de altitude e de vegetação. Foi elaborado gradiente de ordenação direto da abundância de espécies de marsupial, de primatas e de roedores com a altitude. Foram coletadas ou relatadas 69 espécies de mamíferos para o maciço do Itatiaia, pertencendo a 7 ordens e 20 famílias. Dessas, 33 espécies (47,8%) estão incluídas na lista oficial de espécies ameaçadas de extinção, ou presumivelmente ameaçadas, do Estado do Rio de Janeiro. As ordens Rodentia, Carnivora e Didelphimorphia apresentaram as mais altas riquezas de espécies, com 25, 14 e 13 espécies, respectivamente. Quando agrupadas de acordo com a vegetação, 16 espécies ocorreram na Floresta Submontana, 56 ocorreram na Floresta Montana, 5, na Floresta Alto-Montana e 21, nos Campos de Altitude. As comunidades de marsupiais, primatas e roedores têm padrão de ordenação relacionado com a altitude. A riqueza de espécies foi maior entre 500 m e 1.500 m, na Floresta Montana, o que está de acordo com estudos recentes que mostram que a riqueza de espécies alcança seu valor máximo em elevações medianas.