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1.
PLoS One ; 12(8): e0180397, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28767644

RESUMO

The Hajar Mountains of south-eastern Arabia form an isolated massif surrounded by the sea to the east and by a large desert to the west. As a result of their old geological origin, geographical isolation, complex topography and local climate, these mountains provide an important refuge for endemic and relict species of plants and animals. With 19 species restricted to the Hajar Mountains, reptiles are the vertebrate group with the highest level of endemicity, becoming an excellent model for understanding the patterns and processes that generate and shape diversity in this arid mountain range. The geckos of the Ptyodactylus hasselquistii species complex are the largest geckos in Arabia and are found widely distributed across the Arabian Mountains, constituting a very important component of the reptile mountain fauna. Preliminary analyses suggested that their diversity in the Hajar Mountains may be higher than expected and that their systematics should be revised. In order to tackle these questions, we inferred a nearly complete calibrated phylogeny of the genus Ptyodactylus to identify the origin of the Hajar Mountains lineages using information from two mitochondrial and four nuclear genes. Genetic variability within the Hajar Mountains was further investigated using 68 specimens of Ptyodactylus from 46 localities distributed across the entire mountain range and sequenced for the same genes as above. The molecular phylogenies and morphological analyses as well as niche comparisons indicate the presence of two very old sister cryptic species living in allopatry: one restricted to the extreme northern Hajar Mountains and described as a new species herein; the other distributed across the rest of the Hajar Mountains that can be confidently assigned to the species P. orlovi. Similar to recent findings in the geckos of the genus Asaccus, the results of the present study uncover more hidden diversity in the northern Hajar Mountains and stress once again the importance of this unique mountain range as a hot spot of biodiversity and a priority focal point for reptile conservation in Arabia.


Assuntos
Classificação , Variação Genética , Lagartos/classificação , Animais , Citocromos b/genética , DNA/química , DNA/genética , DNA/isolamento & purificação , DNA Mitocondrial/química , DNA Mitocondrial/genética , Ecossistema , Evolução Molecular , Feminino , Haplótipos , Lagartos/genética , Masculino , Omã , Filogenia , Filogeografia , Proteínas Proto-Oncogênicas c-mos/genética , RNA Ribossômico/genética , Receptor Tipo 1 de Melanocortina/genética , Análise de Sequência de DNA , Emirados Árabes Unidos
2.
Acta Vet Hung ; 63(3): 358-69, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26551426

RESUMO

Nosema ceranae is present in honey bee (Apis mellifera L.) colonies worldwide. Studies on the comparative virulence of N. ceranae and N. apis showed significant differences in individual mortality, and the prevalence of N. ceranae seems to be predominant in both the continental and the Mediterranean climate regions. This study attempted to monitor the geographical and seasonal distribution of these two Nosema species in Hungary, using a simple laboratory method. The distribution of N. ceranae and N. apis infection rates along all seasons was homogeneous (P = 0.57). In co-infected samples, the intensity of N. ceranae infection was always significantly higher than that of N. apis infection (P < 0.001). The infection rate of infected bees in exterior samples was higher than in interior samples in each season; however, the differences were not statistically significant. The species N. ceranae had been present in Hungary already in 2004. Statistical analysis of data shows that the infection level is best represented by sampling exterior bees to establish the proportion of infected bees rather than by determining the mean spore count.

3.
Acta Biochim Pol ; 62(2): 273-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26098715

RESUMO

The current knowledge and documentation on the origins and relationship between Gyimesi Racka reared in Hungary and the Romanian Turcana is rather controversial. Lack of information and scientific reliable proofs for the divergent theories found in the two countries motivated us to implement a trial using molecular methods to assess the genetic distance and diversity in the two breeds. Hair follicles were collected from Gyimesi Racka (2 phenotypes) and from Turcana (6 ecotypes). The 599 bp segment of the D-loop region of the mitochondrial DNA was sequenced. Altogether, 42 haplotypes were identified, while 23 were found in both populations. Populations were highly diverse according to the haplotype and nucleotide diversity indices. AMOVA analysis showed that most of the variation was observed within populations (98%), indicating a weak genetic structure between the two breeds. Animals were grouped into seven groups based on their phenotype; however genetic distances among them were also low. Tajima's D, Fu's Fs, goodness-of-fit statistics, mismatch distribution and network analysis suggested recent demographic expansion. Current comprehensive mtDNA study indicates that there is very low level of genetic differentiation between the Gyimesi Racka and Turcana populations therefore they are de facto one trans-boundary breed.


Assuntos
DNA Mitocondrial , Variação Genética , Carneiro Doméstico/genética , Animais , Genética Populacional , Cabelo/fisiologia , Hungria , Roma (Grupo Étnico)
4.
Ecol Evol ; 5(23): 5456-67, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27069597

RESUMO

Carniolan honey bees (Apis mellifera carnica) are considered as an indigenous subspecies in Hungary adapted to most of the ecological and climatic conditions in this area. However, during the last decades Hungarian beekeepers have recognized morphological signs of the Italian honey bee (Apis mellifera ligustica). As the natural distribution of the honey bee subspecies can be affected by the importation of honey bee queens or by natural gene flow, we aimed at determining the genetic structure and characteristics of the local honey bee population using molecular markers. All together, 48 Hungarian and 84 foreign (Italian, Polish, Spanish, Liberian) pupae and/or workers were used for mitochondrial DNA analysis. Additionally, 53 sequences corresponding to 10 subspecies and the Buckfast hybrid were downloaded from GenBank. For the nuclear analysis, 236 Hungarian and 106 foreign honey bees were genotyped using nine microsatellites. Heterozygosity values, population-specific alleles, FST values, principal coordinate analysis, assignment tests, structure analysis, and dendrograms were calculated. Haplotype and nucleotide diversity values showed moderate values. We found that one haplotype (H9) was dominant in Hungary. The presence of the black honey bee (Apis mellifera mellifera) was negligible, but a few individuals resembling other subspecies were identified. We proved that the Hungarian honey bee population is nearly homogeneous but also demonstrated introgression from the foreign subspecies. Both mitochondrial DNA and microsatellite analyses corroborated the observations of the beekeepers. Molecular analyses suggested that Carniolan honey bee in Hungary is slightly affected by Italian and black honey bee introgression. Genetic differences were detected between Polish and Hungarian Carniolan honey bee populations, suggesting the existence of at least two different gene pools within A. m. carnica.

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