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1.
Mol Phylogenet Evol ; 188: 107890, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37517508

RESUMO

African-Malagasy species of the bat genus Miniopterus are notable both for the dramatic increase in the number of newly recognized species over the last 15 years, as well as for the profusion of new taxa from Madagascar and the neighboring Comoros. Since 2007, seven new Malagasy Miniopterus species have been described compared to only two new species since 1936 from the Afrotropics. The conservative morphology of Miniopterus and limited geographic sampling in continental Africa have undoubtedly contributed to the deficit of continental species. In addition to uncertainty over species limits, phylogenetic relationships of Miniopterus remain mostly unresolved, particularly at deeper backbone nodes. Previous phylogenetic studies were based on limited taxon sampling and/or limited genetic sampling involving no more than five loci. Here, we conduct the first phylogenomic study of the Afrotropical Miniopteridae by analyzing up to 3772 genome-wide ultraconserved elements (UCEs) from historic and modern samples of 70 individuals from 25 Miniopterus species/lineages. We analyze multiple datasets of varying degrees of completeness (70, 90, and 100 percent complete) using partitioned concatenated maximum likelihood and multispecies coalescent methods. Our well-supported, species-level phylogenies resolved most (6/8 or 7/8) backbone nodes and strongly support for the first time the monophyly of the Malagasy radiation. We inferred the crown age of African Miniopteridae in the late Miocene (10.4 Ma), while the main lineages of Miniopterus appear to have contemporaneously diversified in two sister radiations in the Afrotropics and Madagascar. Species-level divergence of 23 of 25 African + Malagasy Miniopterus were estimated to have 95 % HPDs that overlap with the late Miocene (5.3-10.4 Ma). We present ancestral range estimates that unambiguously support a continental African radiation that originated in the Zambezian and Somalian/Ethiopian biogeographic regions, but we cannot rule out back colonization of Africa from Madagascar. The phylogeny indicates genetic support for up to seven new species.


Assuntos
Quirópteros , Humanos , Animais , Filogenia , Quirópteros/genética , África , Madagáscar
2.
Syst Parasitol ; 100(6): 745-750, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37874423

RESUMO

Ixodes (Afrixodes) ambohitantelensis n. sp. (Acari: Ixodidae) is described based on females ex endemic shrew tenrecs (Afrosoricida: Tenrecidae) and an introduced rodent (Rodentia: Muridae) from Madagascar. Females of this new species are similar to those of other species of the subgenus Afrixodes Morel, 1966, known from Madagascar, from which they can be distinguished by the size of scutum, size of scutal setae, shape of alloscutal setae, development of genital apron, size of auriculae, size of anterior angle of basis capituli, size of palpi, dental formula on hypostome, development of syncoxae, and size and development of spurs on coxae I and IV.


Assuntos
Ixodes , Ixodidae , Parasitos , Feminino , Animais , Tenrecidae , Roedores/parasitologia , Musaranhos , Muridae , Afrotheria , Madagáscar , Especificidade da Espécie
3.
Emerg Infect Dis ; 28(12): 2583-2585, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36418002

RESUMO

We detected Bombali ebolavirus RNA in 3 free-tailed bats (Mops condylurus, Molossidae) in Mozambique. Sequencing of the large protein gene revealed 98% identity with viruses previously detected in Sierra Leone, Kenya, and Guinea. Our findings further support the suspected role of Mops condylurus bats in maintaining Bombali ebolavirus.


Assuntos
Quirópteros , Ebolavirus , Animais , Ebolavirus/genética , Moçambique/epidemiologia , Guiné/epidemiologia , Quênia
4.
Virol J ; 18(1): 205, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641936

RESUMO

Co-infections have a key role in virus transmission in wild reservoir hosts. We investigated the simultaneous presence of astroviruses, coronaviruses, and paramyxoviruses in bats from Madagascar, Mayotte, Mozambique, and Reunion Island. A total of 871 samples from 28 bat species representing 8 families were tested by polymerase chain reactions (PCRs) targeting the RNA-dependent RNA-polymerase genes. Overall, 2.4% of bats tested positive for the presence of at least two viruses, only on Madagascar and in Mozambique. Significant variation in the proportion of co-infections was detected among bat species, and some combinations of co-infection were more common than others. Our findings support that co-infections of the three targeted viruses occur in bats in the western Indian Ocean region, although further studies are needed to assess their epidemiological consequences.


Assuntos
Infecções por Astroviridae/epidemiologia , Quirópteros/virologia , Coinfecção/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Paramyxoviridae/epidemiologia , Animais , Madagáscar , Moçambique , Reunião
5.
Malar J ; 20(1): 157, 2021 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-33743716

RESUMO

BACKGROUND: Numerous studies have been undertaken to advance knowledge of apicomplexan parasites infecting vertebrates, including humans. Of these parasites, the genus Plasmodium has been most extensively studied because of the socio-economic and public health impacts of malaria. In non-human vertebrates, studies on malaria or malaria-like parasite groups have been conducted but information is far from complete. In Madagascar, recent studies on bat blood parasites indicate that three chiropteran families (Miniopteridae, Rhinonycteridae, and Vespertilionidae) are infected by the genus Polychromophilus with pronounced host specificity: Miniopterus spp. (Miniopteridae) harbour Polychromophilus melanipherus and Myotis goudoti (Vespertilionidae) is infected by Polychromophilus murinus. However, most of the individuals analysed in previous studies were sampled on the western and central portions of the island. The aims of this study are (1) to add new information on bat blood parasites in eastern Madagascar, and (2) to highlight biotic and abiotic variables driving prevalence across the island. METHODS: Fieldworks were undertaken from 2014 to 2016 in four sites in the eastern portion of Madagascar to capture bats and collect biological samples. Morphological and molecular techniques were used to identify the presence of haemosporidian parasites. Further, a MaxEnt modelling was undertaken using data from Polychromophilus melanipherus to identify variables influencing the presence of this parasite RESULTS: In total, 222 individual bats belonging to 17 species and seven families were analysed. Polychromophilus infections were identified in two families: Miniopteridae and Vespertilionidae. Molecular data showed that Polychromophilus spp. parasitizing Malagasy bats form a monophyletic group composed of three distinct clades displaying marked host specificity. In addition to P. melanipherus and P. murinus, hosted by Miniopterus spp. and Myotis goudoti, respectively, a novel Polychromophilus lineage was identified from a single individual of Scotophilus robustus. Based on the present study and the literature, different biotic and abiotic factors are shown to influence Polychromophilus infection in bats, which are correlated based on MaxEnt modelling. CONCLUSIONS: The present study improves current knowledge on Polychromophilus blood parasites infecting Malagasy bats and confirms the existence of a novel Polychromophilus lineage in Scotophilus bats. Additional studies are needed to obtain additional material of this novel lineage to resolve its taxonomic relationship with known members of the genus. Further, the transmission mode of Polychromophilus in bats as well as its potential effect on bat populations should be investigated to complement the results provided by MaxEnt modelling and eventually provide a comprehensive picture of the biology of host-parasite interactions.


Assuntos
Quirópteros , Haemosporida/fisiologia , Interações Hospedeiro-Parasita , Infecções Protozoárias em Animais/epidemiologia , Animais , Madagáscar/epidemiologia , Filogenia , Prevalência , Infecções Protozoárias em Animais/classificação , Infecções Protozoárias em Animais/parasitologia , Análise de Sequência de DNA/veterinária
6.
Mol Ecol ; 29(9): 1717-1729, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32270561

RESUMO

Madagascar's shrew tenrecs (Mammalia: Tenrecidae; Microgale, Nesogale) represent an excellent system for studying speciation. Most species are endemic to the island's eastern humid forests, a region renowned for high levels of biodiversity and a high rate of in situ diversification. We set out to understand the speciation dynamics in a clade of recently described taxa: Microgale fotsifotsy and M. soricoides, which have nearly identical distributions in the moist evergreen forest, and M. nasoloi, which occurs in the western dry deciduous forest. A phylogenetic analysis using mitochondrial DNA data recovered two distinct clades of M. fotsifotsy: a south clade that is sister to, and broadly sympatric with, M. soricoides, and a north clade that is sister to the dry-forest and distantly allopatric species M. nasoloi. To better understand this result, we analysed cranioskeletal measurements and performed demographic analyses using nuclear sequence data from ultraconserved elements. Nuclear data did not support a sister relationship between M. soricoides and the south clade of M. fotsifotsy but did demonstrate introgression between these clades, which probably explains the discordance between nuclear and mitochondrial phylogenies. Demographic analyses also revealed the absence of gene flow between the north and south clades of M. fotsifotsy. Morphometric data revealed several major differences between M. soricoides and M. fotsifotsy, as well as more subtle differences between the two clades of M. fotsifotsy. In light of these results, we treat the south clade of M. fotsifotsy as a new candidate species. Our findings demonstrate the utility of integrating multiple data types to understand complex speciation histories, and contribute to a growing body of evidence that species diversity on Madagascar is underestimated.


Assuntos
Eutérios/genética , Fluxo Gênico , Especiação Genética , Simpatria , Animais , DNA Mitocondrial/genética , Eutérios/classificação , Madagáscar , Filogenia
7.
Mol Phylogenet Evol ; 144: 106700, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31809850

RESUMO

Madagascar's biota is characterized by a high degree of microendemism at different taxonomic levels, but how colonization and in-situ speciation contribute to the assembly of local species communities has rarely been studied on this island. Here we analyze the phylogenetic relationships of riparian frogs of the Mantidactylus ambreensis species complex, which is distributed in the north of Madagascar and was originally described from Montagne d'Ambre, an isolated mountain of volcanic origin, currently protected within Montagne d'Ambre National Park (MANP). Data from mitochondrial DNA, and phylogenomic data from FrogCap, a sequence capture method, independently confirm that this species complex is monophyletic within the subgenus Ochthomantis, and identify two main clades within it. These two clades are separated by 5.6-6.8% pairwise distance in the mitochondrial 16S rRNA gene and co-occur in MANP, with one distributed at high elevations (940-1375 m a.s.l.) and the other at lower elevations (535-1010 m a.s.l.), but show almost no haplotype sharing in the nuclear RAG1 gene. This occurrence in syntopy without admixture confirms them as independent evolutionary lineages that merit recognition as separate species, and we here refer to them as high-elevation (HE) and low-elevation (LE) lineage; they will warrant taxonomic assessment to confidently assign the name ambreensis to one or the other. Populations of the M. ambreensis complex from elsewhere in northern Madagascar all belong to the LE lineage, although they do occur over a larger elevational range than in Montagne d'Ambre (285-1040 m a.s.l.). Within LE there are several phylogroups (LE1-LE4) of moderately deep divergence (1.5-2.8% in 16S), but phylogroup LE4 that occurs in MANP has a deeply nested phylogenetic position, as recovered separately by mitochondrial and sequence capture datasets. This suggests that HE and LE did not diverge by a local fission of lower and upper populations, but instead arose through a more complex biogeographic scenario. The branching pattern of phylogroups LE1-LE4 shows a clear south-to-north phylogeographic pattern. We derive from these results a testable hypothesis of vicariant speciation that restricted the HE lineage to MANP and the LE candidate species to a climatic refugium further south, with subsequent northwards range expansion and secondary colonization of MANP by LE. These results provide an example for complex assembly of local microendemic amphibian faunas on Madagascar.


Assuntos
Anuros/classificação , Anuros/genética , Especiação Genética , Simpatria/fisiologia , Animais , Núcleo Celular/genética , DNA Mitocondrial/genética , Genes RAG-1 , Madagáscar , Filogenia , Filogeografia , RNA Ribossômico 16S
8.
Syst Parasitol ; 97(6): 591-599, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33063166

RESUMO

Haemaphysalis (Rhipistoma) galidiae n. sp. (Acari: Ixodidae) is described herein based on males and a single female. Adults of H. galidiae n. sp. were collected from the ring-tailed vontsira, Galidia elegans Geoffroy Saint-Hilaire (Carnivora: Eupleridae) on Madagascar. Males and the single female of this new species morphologically are most close to H. obtusa Dönitz, 1910, known from various Malagasy euplerid carnivorans, including G. elegans, as well as introduced carnivorans, but can be differentiated from it by the shape of the female genital aperture, shape of posterolateral margin of palpal segment II ventrally in both male and female and shape and size of spurs on palpal segment II, coxa I and trochanter I in both sexes.


Assuntos
Eupleridae/parasitologia , Ixodidae/anatomia & histologia , Ixodidae/classificação , Animais , Feminino , Madagáscar , Masculino , Especificidade da Espécie
9.
Syst Parasitol ; 97(6): 623-637, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33150511

RESUMO

Ixodes soarimalalae n. sp., Ixodes uilenbergi n. sp. and Ixodes uncus n. sp. (Acari: Ixodidae), are described based on females ex various species of tenrecs (Afrosoricida: Tenrecidae) from Madagascar. Females of all of these new species are similar to those of other species of the subgenus Afrixodes Morel, 1966 known from Madagascar, from which they can be distinguished and from one other by the size of scutum, size of scutal setae, shape of alloscutal setae, shape of genital aperture, development of genital apron, size of auriculae, size of anterior angle of basis capituli, size of palpi, dental formula on hypostome and size and development of spurs on coxa I.


Assuntos
Ixodes/classificação , Mamíferos/parasitologia , Animais , Ixodes/anatomia & histologia , Madagáscar , Especificidade da Espécie
10.
BMC Evol Biol ; 19(1): 166, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31434566

RESUMO

BACKGROUND: The Old World insectivorous bat genus Rhinolophus is highly speciose. Over the last 15 years, the number of its recognized species has grown from 77 to 106, but knowledge of their interrelationships has not kept pace. Species limits and phylogenetic relationships of this morphologically conservative group remain problematic due both to poor sampling across the Afrotropics and to repeated instances of mitochondrial-nuclear discordance. Recent intensive surveys in East Africa and neighboring regions, coupled with parallel studies by others in West Africa and in Southern Africa, offer a new basis for understanding its evolutionary history. RESULTS: We investigated phylogenetic relationships and intraspecific genetic variation in the Afro-Palearctic clade of Rhinolophidae using broad sampling. We sequenced mitochondrial cytochrome-b (1140 bp) and four independent and informative nuclear introns (2611 bp) for 213 individuals and incorporated sequence data from 210 additional individuals on GenBank that together represent 24 of the 33 currently recognized Afrotropical Rhinolophus species. We addressed the widespread occurrence of mito-nuclear discordance in Rhinolophus by inferring concatenated and species tree phylogenies using only the nuclear data. Well resolved mitochondrial, concatenated nuclear, and species trees revealed phylogenetic relationships and population structure of the Afrotropical species and species groups. CONCLUSIONS: Multiple well-supported and deeply divergent lineages were resolved in each of the six African Rhinolophus species groups analyzed, suggesting as many as 12 undescribed cryptic species; these include several instances of sympatry among close relatives. Coalescent lineage delimitation offered support for new undescribed lineages in four of the six African groups in this study. On the other hand, two to five currently recognized species may be invalid based on combined mitochondrial and/or nuclear phylogenetic analyses. Validation of these cryptic lineages as species and formal relegation of current names to synonymy will require integrative taxonomic assessments involving morphology, ecology, acoustics, distribution, and behavior. The resulting phylogenetic framework offers a powerful basis for addressing questions regarding their ecology and evolution.


Assuntos
Quirópteros/classificação , Quirópteros/genética , Filogenia , África , Animais , Núcleo Celular/genética , Citocromos b/genética , DNA Mitocondrial/genética , Íntrons , Simpatria
11.
Mol Phylogenet Evol ; 139: 106535, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31207284

RESUMO

Madagascar is known as a biodiversity hotspot, providing an ideal natural laboratory for investigating the processes of avian diversification. Yet, the phylogeography of Madagascar's avifauna is still largely unexamined. In this study, we evaluated phylogeographic patterns and species limits within the Rufous Vanga, Schetba rufa, a monotypic genus of forest-dwelling birds endemic to the island. Using an integrative taxonomic approach, we synthesized data from over 4000 ultra-conserved element (UCE) loci, mitochondrial DNA, multivariate morphometrics, and ecological niche modeling to uncover two reciprocally monophyletic, geographically circumscribed, and morphologically distinct clades of Schetba. The two lineages are restricted to eastern and western Madagascar, respectively, with distributions broadly consistent with previously described subspecies. Based on their genetic and morphological distinctiveness, the two subspecies merit recognition as separate species. The bioclimatic transition between the humid east and dry west of Madagascar likely promoted population subdivision and drove speciation in Schetba during the Pleistocene. Our study is the first evidence that an East-West bioclimatic transition zone played a role in the speciation of birds within Madagascar.


Assuntos
Clima , Especiação Genética , Passeriformes/classificação , Filogeografia , Animais , Sequência de Bases , Biodiversidade , Análise por Conglomerados , DNA Mitocondrial/genética , Florestas , Loci Gênicos , Geografia , Ilhas , Madagáscar , Passeriformes/anatomia & histologia , Passeriformes/genética , Filogenia , Análise de Componente Principal
12.
J Zool Syst Evol Res ; 57(4): 1019-1038, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31894177

RESUMO

The bat family Nycteridae contains only the genus Nycteris, which comprises 13 currently recognized species from Africa and the Arabian Peninsula, one species from Madagascar, and two species restricted to Malaysia and Indonesia in South-East Asia. We investigated genetic variation, clade membership, and phylogenetic relationships in Nycteridae with broad sampling across Africa for most clades. We sequenced mitochondrial cytochrome b (cytb) and four independent nuclear introns (2,166 bp) from 253 individuals. Although our samples did not include all recognized species, we recovered at least 16 deeply divergent monophyletic lineages using independent mitochondrial and multilocus nuclear datasets in both gene tree and species tree analyses. Mean pairwise uncorrected genetic distances among species-ranked Nycteris clades (17% for cytb and 4% for concatenated introns) suggest high levels of phylogenetic diversity in Nycteridae. We found a large number of designated clades whose members are distributed wholly or partly in East Africa (10 of 16 clades), indicating that Nycteris diversity has been historically underestimated and raising the possibility that additional unsampled and/or undescribed Nycteris species occur in more poorly sampled Central and West Africa. Well-resolved mitochondrial, concatenated nuclear, and species trees strongly supported African ancestry for SE Asian species. Species tree analyses strongly support two deeply diverged subclades that have not previously been recognized, and these clades may warrant recognition as subgenera. Our analyses also strongly support four traditionally recognized species groups of Nycteris. Mitonuclear discordance regarding geographic population structure in Nycteris thebaica appears to result from male-biased dispersal in this species. Our analyses, almost wholly based on museum voucher specimens, serve to identify species-rank clades that can be tested with independent datasets, such as morphology, vocalizations, distributions, and ectoparasites. Our analyses highlight the need for a comprehensive revision of Nycteridae.

13.
Proc Natl Acad Sci U S A ; 113(29): 8049-56, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27432945

RESUMO

Phylogeographic analysis can be described as the study of the geological and climatological processes that have produced contemporary geographic distributions of populations and species. Here, we attempt to understand how the dynamic process of landscape change on Madagascar has shaped the distribution of a targeted clade of mouse lemurs (genus Microcebus) and, conversely, how phylogenetic and population genetic patterns in these small primates can reciprocally advance our understanding of Madagascar's prehuman environment. The degree to which human activity has impacted the natural plant communities of Madagascar is of critical and enduring interest. Today, the eastern rainforests are separated from the dry deciduous forests of the west by a large expanse of presumed anthropogenic grassland savanna, dominated by the Family Poaceae, that blankets most of the Central Highlands. Although there is firm consensus that anthropogenic activities have transformed the original vegetation through agricultural and pastoral practices, the degree to which closed-canopy forest extended from the east to the west remains debated. Phylogenetic and population genetic patterns in a five-species clade of mouse lemurs suggest that longitudinal dispersal across the island was readily achieved throughout the Pleistocene, apparently ending at ∼55 ka. By examining patterns of both inter- and intraspecific genetic diversity in mouse lemur species found in the eastern, western, and Central Highland zones, we conclude that the natural environment of the Central Highlands would have been mosaic, consisting of a matrix of wooded savanna that formed a transitional zone between the extremes of humid eastern and dry western forest types.


Assuntos
Cheirogaleidae/genética , Animais , DNA Mitocondrial/genética , Florestas , Madagáscar , Filogenia , Filogeografia
14.
Mol Phylogenet Evol ; 126: 74-84, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29501374

RESUMO

Madagascar is one of the world's foremost biodiversity hotspots, yet a large portion of its flora and fauna remains undescribed and the driving forces of in situ diversification are not well understood. Recent studies have identified a widespread, latitudinally structured phylogeographic pattern in Madagascar's humid-forest mammals, amphibians, reptiles, and insects. Several factors may be driving this pattern, namely biogeographic barriers (i.e., rivers or valleys) or past episodes of forest contraction and expansion. In this study, we describe the phylogeographic structure of the small, semifossorial mammal Oryzorictes hova, one of Madagascar's two species of mole tenrec, found throughout Madagascar's eastern humid forest belt, from high-elevation montane forest to low-elevation forests, as well as disturbed habitat such as rice fields. Using one mitochondrial locus, four nuclear loci, and 31 craniomandibular measurements, we identified three distinct populations of O. hova associated with the northern, central, and southern regions of the island. We found little evidence of gene flow among these populations, so we treated each population as a potential species. We validated species limits using two Bayesian methods: BP&P, employing only DNA sequence data, and iBPP using both DNA and morphological data, and we assessed whether these methods are susceptible to producing false positive errors. Molecular and morphological data support the recognition of each of the three populations of O. hova as distinct species, but formal species descriptions will require additional data from type specimens. This study illustrates the importance of using integrative datasets, multiple methodological approaches, and extensive geographic sampling for species delimitation and adds evidence for a widespread phylogeographic pattern in Madagascar's humid forest taxa.


Assuntos
Altitude , Especiação Genética , Mamíferos/genética , Animais , Teorema de Bayes , Biodiversidade , Genética Populacional , Haplótipos/genética , Madagáscar , Filogenia , Filogeografia , Análise de Componente Principal , Especificidade da Espécie , Fatores de Tempo
15.
Mol Phylogenet Evol ; 124: 16-26, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29474976

RESUMO

Madagascar is renowned as a global biodiversity hotspot with high levels of microendemism. However, there are few molecular phylogenetic studies of Malagasy birds, particularly for forest-dwelling species, signifying a substantial gap in current measures of species diversity in the absence of genetic data. We evaluated species limits and explored patterns of diversification within the genus Newtonia (Family Vangidae), a group of forest-dwelling songbirds endemic to Madagascar. Our modern systematics approach combined genomic, morphometric, and ecological niche data to analyze the evolutionary history of the group. Our integrative analysis uncovered hidden species-level diversity within N. amphichroa, with two deeply divergent and morphologically distinct lineages isolated in different regions of humid forest. We describe the southern lineage as a new species. Conversely, N. brunneicauda, which we initially hypothesized may harbor cryptic diversity owing to its large distribution spanning a range of habitats, was found to have no distinct lineages and shared haplotypes across much of its distribution. The contrasting diversification patterns between Newtonia lineages may be the result of their elevational tolerances. Newtonia brunneicauda has a broad habitat tolerance and elevational range that appears to have facilitated population expansion and gene flow across the island, limiting opportunities for diversification. On the other hand, N. amphichroa is found predominantly in mid-elevation and montane humid forests, a restriction that appears to have promoted speciation associated with climatic fluctuations during the Pleistocene. Our findings indicate that species diversity of Malagasy forest-dwelling birds may be greater than currently recognized, suggesting an urgent need for further studies to quantify biodiversity in Madagascar's rapidly disappearing native forests.


Assuntos
Biodiversidade , Aves/classificação , Florestas , Filogenia , Animais , Sequência de Bases , Aves/anatomia & histologia , Fluxo Gênico , Loci Gênicos , Haplótipos/genética , Ilhas , Funções Verossimilhança , Madagáscar , Filogeografia , Análise de Componente Principal , Especificidade da Espécie
16.
Virol J ; 15(1): 104, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925396

RESUMO

Astroviruses (AstVs) are responsible for infection of a large diversity of mammalian and avian species, including bats, aquatic birds, livestock and humans. We investigated AstVs circulation in bats in Mozambique and Mayotte, a small island in the Comoros Archipelago located between east Africa and Madagascar. Biological material was collected from 338 bats and tested for the presence of the AstV RNA-dependent RNA-polymerase gene with a pan-AstV semi-nested polymerase chain reaction assay. None of the 79 samples obtained from Mayotte bats (Pteropus seychellensis comorensis and Chaerephon pusillus) tested positive; however, 20.1% of bats sampled in Mozambique shed AstVs at the time of sampling and significant interspecific variation in the proportion of positive bats was detected. Many AstVs sequences obtained from a given bat species clustered in different phylogenetic lineages, while others seem to reflect some level of host-virus association, but also with AstVs previously reported from Malagasy bats. Our findings support active circulation of a large diversity of AstVs in bats in the western Indian Ocean islands, including the southeastern African coast, and highlight the need for more detailed assessment of its risk of zoonotic transmission to human populations.


Assuntos
Doenças dos Animais/virologia , Infecções por Astroviridae/veterinária , Astroviridae , Quirópteros/virologia , Doenças dos Animais/epidemiologia , Animais , Genes Virais , Moçambique/epidemiologia , Filogenia , RNA Viral
17.
Malar J ; 17(1): 318, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30170583

RESUMO

BACKGROUND: Bats are home to diverse haemosporidian parasites namely Plasmodium and Plasmodium-related. While information is available at a worldwide level, haemosporidian infection in bats from Madagascar is still scarce and recent changes in the taxonomy of the island's bat fauna, particularly the description of several new species, require a reassessment of previously described patterns, including blood parasite ecology and vectorial transmission. METHODS: A sample representing seven of the nine known bat families and 31 of the 46 currently recognized taxa from Madagascar and collected in the western and central portions of the island were screened by PCR for the presence of Polychromophilus. In addition, Nycteribiidae flies parasitizing Miniopteridae and Vespertilionidae were screened for parasites with the aim to better understand aspects of vector transmission. Phylogenetic reconstruction using the mitochondrial cytochrome b encoding gene was used in a Bayesian analysis to examine the relationship between Polychromophilus recovered from Malagasy bats and those identified elsewhere. RESULTS: Polychromophilus infection was restricted to Miniopterus spp. (Miniopteridae), Myotis goudoti (Vespertilionidae), and Paratriaenops furculus (Rhinonycteridae), with an overall infection rate of 13.5%. Polychromophilus melanipherus was found infecting Miniopterus spp. and P. furculus, whereas Polychromophilus murinus was only recovered from M. goudoti. These two protozoan parasites species were also detected in bat flies species known to parasitize Miniopterus spp. and M. goudoti, respectively. Generalized linear model analyses were conducted to elucidate the effect of species and sex on haemoparasites infection in Miniopterus spp., which revealed that males have higher risk of infection than females and prevalence differed according to the considered Miniopterus host. Molecular screening of nycteribiid flies revealed three positive species for Polychromophilus spp., including Penicillidia sp. (cf. fulvida), Penicillidia leptothrinax, and Nycteribia stylidiopsis. These three fly species are known to parasitize Miniopterus spp. and M. goudoti and should be considered as potential vectors of Polychromophilus spp. CONCLUSION: Phylogenetic analyses demonstrated the existence of at least four distinct clades within the genus Polychromophilus, two of which were documented in the present study. The screening of nycteribiid flies overlaid on the highly diversified genus Miniopterus, provides considerable insight into parasite transmission, with bat infection being associated with their roosting behaviour and the occurrence of specific arthropod vectors.


Assuntos
Quirópteros , Dípteros/parasitologia , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Animais , Teorema de Bayes , Quirópteros/classificação , Citocromos b/análise , Feminino , Especificidade de Hospedeiro , Madagáscar/epidemiologia , Masculino , Proteínas Mitocondriais/análise , Filogenia , Infecções Protozoárias em Animais/parasitologia , Infecções Protozoárias em Animais/transmissão , Análise de Sequência de DNA/veterinária
18.
Naturwissenschaften ; 105(7-8): 44, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-29959538

RESUMO

We applied a multi-isotope approach to examine aspects of niche partitioning, competition, and mobility for rodents in the Central Highlands of Madagascar. Specifically, we used carbon (δ13C), nitrogen (δ15N), and strontium (87Sr/86Sr) isotope ratios in bone to investigate diet and mobility for endemic tufted tail rats (Eliurus spp.), and introduced black rats (Rattus rattus) and house mice (Mus musculus) within and outside a fragment of montane humid forest in the Ambohitantely Special Reserve. There was a clear spatial segregation in trapping success for different species: Eliurus was only in the forest interior and edge, Mus only outside of the fragment in a marsh and park housing complex, and Rattus in all habitats except the housing complex. We find only moderate support for mobility of rodents among habitats. Mus may routinely move between the marsh and housing complex. However, regular movement between the forest edge and interior, or between the forest fragment and surrounding grassland is not supported. Taxa appear to target different foods: Rattus tends to feed at a higher trophic level than Eliurus, and Mus consumes some C4 resources. To date, strontium isotopes have been underutilized in ecological research. Here, we show that they are highly complementary to carbon and nitrogen isotope data. Even in localities with relatively uniform underlying geology, it may be possible to distinguish individuals that regularly forage in different habitats.


Assuntos
Ecossistema , Isótopos/análise , Roedores/fisiologia , Animais , Isótopos de Carbono/análise , Madagáscar , Camundongos , Isótopos de Nitrogênio/análise , Ratos , Isótopos de Estrôncio/análise
19.
Syst Biol ; 65(5): 890-909, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27103169

RESUMO

The family Tenrecidae (tenrecs) is one of only four extant terrestrial mammal lineages to have colonized and diversified on Madagascar. Over the last 15 years, several studies have disagreed on relationships among major tenrec lineages, resulting in multiple reinterpretations of the number and timing of historical transoceanic dispersal events between Africa and Madagascar. We reconstructed the phylogeny of Tenrecidae using multiple loci from all recognized extant species and estimated divergence timing using six fossil calibrations within Afrotheria. All phylogenetic analyses strongly support monophyly of the Malagasy tenrecs, and our divergence timing analysis places their colonization of the island at 30-56 Ma. Our comprehensive phylogeny supports three important taxonomic revisions that reflect the evolutionary history of tenrecs: (1) we formally elevate the African otter shrews to their own family Potamogalidae, thereby rendering extant Tenrecidae entirely endemic to Madagascar; (2) we subsume the semiaquatic genus Limnogale within the shrew tenrec genus Microgale; and (3) we re-elevate the two largest-bodied shrew tenrecs, Microgale dobsoni and Microgale talazaci, to the genus Nesogale Thomas (1918) Finally, we use recently summarized habitat data to test the hypothesis that diversification rates differ between humid and arid habitats on Madagascar, and we compare three common methods for ancestral biogeographic reconstruction. These analyses suggest higher speciation rates in humid habitats and reveal a minimum of three and more likely five independent transitions to arid habitats. Our results resolve the relationships among previously recalcitrant taxa, illuminate the timing and mechanisms of major biogeographic patterns in an extraordinary example of an island radiation, and permit the first comprehensive, phylogenetically consistent taxonomy of Madagascar's tenrecs.


Assuntos
Filogenia , Musaranhos/classificação , Musaranhos/genética , África , Animais , Ecossistema , Florestas , Especiação Genética , Madagáscar , Fatores de Tempo
20.
J Hered ; 108(3): 270-279, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-27940474

RESUMO

The biogeographic dynamics affecting the Indian subcontinent, East and Southeast Asia during the Plio-Pleistocene has generated complex biodiversity patterns. We assessed the molecular biogeography of the small Indian civet (Viverricula indica) through mitogenome and cytochrome b + control region sequencing of 89 historical and modern samples to (1) establish a time-calibrated phylogeography across the species' native range and (2) test introduction scenarios to western Indian Ocean islands. Bayesian phylogenetic analyses identified 3 geographic lineages (East Asia, sister-group to Southeast Asia and the Indian subcontinent + northern Indochina) diverging 3.2-2.3 million years ago (Mya), with no clear signature of past demographic expansion. Within Southeast Asia, Balinese populations separated from the rest 2.6-1.3 Mya. Western Indian Ocean populations were assigned to the Indian subcontinent + northern Indochina lineage and had the lowest mitochondrial diversity. Approximate Bayesian computation did not distinguish between single versus multiple introduction scenarios. The early diversification of the small Indian civet was likely shaped by humid periods in the Late Pliocene-Early Pleistocene that created evergreen rainforest barriers, generating areas of intra-specific endemism in the Indian subcontinent, East, and Southeast Asia. Later, Pleistocene dispersals through drier conditions in South and Southeast Asia were likely, giving rise to the species' current natural distribution. Our molecular data supported the delineation of only 4 subspecies in V. indica, including an endemic Balinese lineage. Our study also highlighted the influence of prefirst millennium AD introductions to western Indian Ocean islands, with Indian and/or Arab traders probably introducing the species for its civet oil.


Assuntos
Filogenia , Filogeografia , Viverridae/classificação , Viverridae/genética , Animais , Citocromos b/genética , DNA Mitocondrial , Evolução Molecular , Frequência do Gene , Variação Genética , Genoma Mitocondrial , Haplótipos , Ilhas do Oceano Índico
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