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1.
PLoS One ; 13(9): e0201781, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30231059

RESUMEN

The number of species of frogs in the South American genus Adelophryne has increased in recent years, and it has become apparent that this group contains a substantial amount of undescribed diversity. Currently the genus contains nine described species and five candidate species. Here we describe the tenth species of the genus Adelophryne from the municipality of Igrapiúna, southern Bahia state, Brazil. The new species is characterized by its small body size, indistinct tympanum, and two phalanges in the finger IV. The species of the genus are distributed in three groups, Northern Amazonia Clade, Northern Atlantic Forest Clade and Southern Atlantic Forest Clade. The new species is phylogenetically related to species of the Northern Atlantic Forest Clade of Adelophryne and restricted to forested habitat, as typical for other Adelophryne. The species is restricted to the pristine forests in the type locality, and we consider its conservation status as Near Threatened. New morphological and molecular data of other Adelophryne species are presented, extending the distribution of Adelophryne sp. 2, Adelophryne sp. 4, Adelophryne mucronata and Adelophryne glandulata. However, a more comprehensive revision of the diversity and phylogenetic position of most Adelophryne species is needed, and the evolutionary relationships of A. meridionalis and A. pachydactyla remain unknown.


Asunto(s)
Anuros/fisiología , Biodiversidad , Tamaño Corporal/fisiología , Bosques , Animales , Anuros/clasificación , Anuros/genética , Brasil , ADN Mitocondrial/química , ADN Mitocondrial/genética , Geografía , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie
2.
Mol Phylogenet Evol ; 112: 68-78, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28404508

RESUMEN

The Atlantic Forest (AF) of Brazil has long been recognized as a biodiversity conservation hotspot. Despite decades of studies the species inventory of this biome continues to increase with the discovery of cryptic diversity and the description of new species. Different diversification mechanisms have been proposed to explain the diversity in the region, including models of forest dynamics, barriers to gene flow and dispersal. Also, sea level change is thought to have influenced coastal diversification and isolated populations on continental islands. However, the timing and mode of diversification of insular populations in the AF region were rarely investigated. Here, we analyze the phylogeography and species diversity of the small-sized direct-developing frog Ischnocnema parva. These frogs are independent from water bodies but dependent on forest cover and high humidity, and provide good models to understand forest dynamics and insular diversification. Our analysis was based on DNA sequences for one mitochondrial and four nuclear genes of 71 samples from 18 localities including two islands, São Sebastião, municipality of Ilhabela, and Mar Virado, municipality of Ubatuba, both in the state of São Paulo. We use molecular taxonomic methods to show that I. parva is composed of six independently evolving lineages, with the nominal I. parva likely endemic to the type locality. The time-calibrated species tree shows that these lineages have diverged in the Pliocene and Pleistocene, suggesting the persistence of micro-refuges of forest in the AF. For the two insular populations we used approximate Bayesian computation to test different diversification hypotheses. Our findings support isolation with migration for São Sebastião population, with ∼1Mya divergence time, and isolation without migration for Mar Virado population, with ∼13Kya divergence time, suggesting a combination of different processes for diversification on AF islands.


Asunto(s)
Anuros/genética , Biodiversidad , Animales , Anuros/clasificación , Teorema de Bayes , Brasil , ADN Mitocondrial/genética , Femenino , Flujo Génico , Islas , Masculino , Modelos Biológicos , Filogenia , Filogeografía , Bosque Lluvioso , Análisis de Secuencia de ADN
3.
Biota neotrop. (Online, Ed. port.) ; 13(1): 124-132, jan.-mar. 2013. graf, mapas, tab
Artículo en Portugués | LILACS | ID: lil-673156

RESUMEN

A plasticidade adaptativa tem sido postulada como um fator importante para explicar a distribuição e abundância de espécies em habitat com diferentes níveis de variação ambiental e a heterogeneidade ambiental tem sido apontada como responsável pela manutenção, aumento ou diminuição da diversidade. Neste trabalho, determinamos o efeito da periodicidade e estrutura do habitat sobre a riqueza e composição de espécies em três diferentes habitat: córrego (P1), poças temporárias (P2) e represa permanente (P3) em um agrossistema no Cerrado do Brasil central. Nove expedições de campo foram realizadas entre outubro de 2005 e abril de 2007. Os métodos de amostragem por encontro visual e procura auditiva foram utilizados para o registro das espécies. Foram registradas 19 espécies de anuros pertencentes a quatro famílias: Bufonidae (uma espécie), Hylidae (nove espécies), Leptodactylidae (cinco espécies) e Leiuperidae (quatro espécies). Maior riqueza e a abundância foram registradas nas lagoas temporárias (P2), que diferiram significativamente do córrego (P1) e da represa permanente (P3). Dendropsophus nanus, Hypsiboas raniceps e Leptodactylus chaquensis apresentaram forte associação com o sítio P2. Os sítios P2 e P3 apresentaram maior diferenciação entre si na composição de espécies, do que quando comparados ao sítio P1. Apesar dos corpos d'água estudados estarem inseridos em área de intensa agricultura e sofrerem elevado grau de perturbação antrópica, esses ambientes apresentam elevada riqueza de espécies, constituindo-se como importantes refúgios para anurofauna da região. Entretanto, as espécies registradas são associadas a áreas antropizadas ou fitofisionomias abertas sendo favorecidas com a criação de ambientes artificiais como os observados no presente estudo.


Adaptive plasticity has been postulated as one of the integrating factors that explain the distribution and abundance of species on different habitat with different environmental variations. The environmental heterogeneity is the most important factor for the maintenance, increment or decrement of biodiversity. On this study we determined the effect of periodicity and habitat structure on the richness and composition of species of three different habitat: stream (P1), temporary ponds (P2) and permanent dam (P3) in an agrosystem in the Central Brazilian Cerrado. We performed nine excursions to the field during November 2005 to April 2007. We found and registered the species by direct search and vocalization orientation. We identified 19 anuran species belonging to four families: Bufonidae (one species), Hylidae (nine species), Leptodactylidae (five species), and Leiuperidae (four species). The greatest richness and abundance were recorded in temporary ponds (P2), which differed significantly from the stream (P1) and from the permanent dam (P3). Dendropsophus nanus, Hypsiboas raniceps and Leptodactylus chaquensis showed strong association with P2. P2 and P3 showed greater differentiation between themselves in species composition than when compared to P1. Despite the fact that the studied areas are surrounded by intense farming and present a high degree of anthropic disturbance, these areas showed a high species richness being an important refugee for the amphibians, although the species found on this work are usually associated to impacted areas or open phytophysiognomies and are favored with the creation of artificial environments such as those in this study.

4.
Genet Mol Biol ; 34(1): 77-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21637547

RESUMEN

Tetragonisca angustula and Tetragonisca fiebrigi have recently been listed as valid species. This study aimed to cytogenetically investigate both species, emphasizing the new registry of B chromosomes in the tribe Meliponini. We analyzed colonies of T. angustula and T. fiebrigi collected at Tangará da Serra, Mato Grosso, Brazil, through conventional Giemsa staining, C-banding, and base-specific fluorochrome staining (CMA(3)/DAPI). T. angustula showed 2n = 34 chromosomes in females and n = 17 in males, with karyotype formula 2K = 34A(M). T. fiebrigi showed numeric variation, with chromosome number varying from 2n = 34 to 2n = 36 in females and from n = 17 to n = 18 in males, with karyotype formula 2K = 32A(M)+2A(Mc) and 2K = 32A(M)+2A(Mc) + 1 or 2 B-chromosomes. The B chromosomes are heterochromatic. In T. fiebrigi, the CMA(3)/DAPI staining revealed four chromosomes with a CMA(3) positive band. All individuals from the same colony showed the same number of B chromosomes. T. angustula and T. fiebrigi showed karyotype divergence, principally due to the presence of B chromosomes, which are found only in T. fiebrigi. Our data corroborate the status of valid species for both T. angustula and T. fiebrigi, as recently proposed.

5.
Genet. mol. biol ; 34(1): 77-79, 2011. ilus
Artículo en Inglés | LILACS | ID: lil-573701

RESUMEN

Tetragonisca angustula and Tetragonisca fiebrigi have recently been listed as valid species. This study aimed to cytogenetically investigate both species, emphasizing the new registry of B chromosomes in the tribe Meliponini. We analyzed colonies of T. angustula and T. fiebrigi collected at Tangará da Serra, Mato Grosso, Brazil, through conventional Giemsa staining, C-banding, and base-specific fluorochrome staining (CMA3/DAPI). T. angustula showed 2n = 34 chromosomes in females and n = 17 in males, with karyotype formula 2K = 34A M. T. fiebrigi showed numeric variation, with chromosome number varying from 2n = 34 to 2n = 36 in females and from n = 17 to n=18in males, with karyotype formula 2K = 32A M+2A Mc and 2K = 32A M+2A Mc + 1 or 2 B-chromosomes. The B chromosomes are heterochromatic. In T. fiebrigi, the CMA3/DAPI staining revealed four chromosomes with a CMA3 positive band. All individuals from the same colony showed the same number of B chromosomes. T. angustula and T. fiebrigi showed karyotype divergence, principally due to the presence of B chromosomes, which are found only in T. fiebrigi. Our data corroborate the status of valid species for both T. angustula and T. fiebrigi, as recently proposed.

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