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1.
Syst Parasitol ; 100(6): 745-750, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37874423

RESUMEN

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.


Asunto(s)
Ixodes , Ixodidae , Parásitos , Femenino , Animales , Tenrecidae , Roedores/parasitología , Musarañas , Muridae , Afrotheria , Madagascar , Especificidad de la Especie
2.
Pathogens ; 12(7)2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37513706

RESUMEN

Madagascar is home to an extraordinary diversity of endemic mammals hosting several zoonotic pathogens. Although the African origin of Malagasy mammals has been addressed for a number of volant and terrestrial taxa, the origin of their hosted zoonotic pathogens is currently unknown. Using bats and Leptospira infections as a model system, we tested whether Malagasy mammal hosts acquired these infections on the island following colonization events, or alternatively brought these bacteria from continental Africa. We first described the genetic diversity of pathogenic Leptospira infecting bats from Mozambique and then tested through analyses of molecular variance (AMOVA) whether the genetic diversity of Leptospira hosted by bats from Mozambique, Madagascar and Comoros is structured by geography or by their host phylogeny. This study reveals a wide diversity of Leptospira lineages shed by bats from Mozambique. AMOVA strongly supports that the diversity of Leptospira sequences obtained from bats sampled in Mozambique, Madagascar, and Comoros is structured according to bat phylogeny. Presented data show that a number of Leptospira lineages detected in bat congeners from continental Africa and Madagascar are imbedded within monophyletic clades, strongly suggesting that bat colonists have indeed originally crossed the Mozambique Channel while infected with pathogenic Leptospira.

3.
Mol Phylogenet Evol ; 188: 107890, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37517508

RESUMEN

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.


Asunto(s)
Quirópteros , Humanos , Animales , Filogenia , Quirópteros/genética , África , Madagascar
4.
Nat Commun ; 14(1): 14, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36627274

RESUMEN

Many of Madagascar's unique species are threatened with extinction. However, the severity of recent and potential extinctions in a global evolutionary context is unquantified. Here, we compile a phylogenetic dataset for the complete non-marine mammalian biota of Madagascar and estimate natural rates of extinction, colonization, and speciation. We measure how long it would take to restore Madagascar's mammalian biodiversity under these rates, the "evolutionary return time" (ERT). At the time of human arrival there were approximately 250 species of mammals on Madagascar, resulting from 33 colonisation events (28 by bats), but at least 30 of these species have gone extinct since then. We show that the loss of currently threatened species would have a much deeper long-term impact than all the extinctions since human arrival. A return from current to pre-human diversity would take 1.6 million years (Myr) for bats, and 2.9 Myr for non-volant mammals. However, if species currently classified as threatened go extinct, the ERT rises to 2.9 Myr for bats and 23 Myr for non-volant mammals. Our results suggest that an extinction wave with deep evolutionary impact is imminent on Madagascar unless immediate conservation actions are taken.


Asunto(s)
Quirópteros , Animales , Humanos , Filogenia , Quirópteros/genética , Madagascar , Mamíferos/genética , Evolución Biológica , Biodiversidad , Extinción Biológica , Conservación de los Recursos Naturales
5.
bioRxiv ; 2023 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-38187621

RESUMEN

Hantaviruses are globally distributed zoonotic pathogens capable of causing fatal disease in humans. Rodents and other small mammals are the typical reservoirs of hantaviruses, though the particular host varies regionally. Addressing the risk of hantavirus spillover from animal reservoirs to humans requires identifying the local mammal reservoirs and the predictors of infection in those animals, such as their population density and habitat characteristics. We screened native and non-native small mammals and bats in northeastern Madagascar for hantavirus infection to investigate the influence of habitat, including effects of human land use on viral prevalence. We trapped 227 bats and 1663 small mammals over 5 successive years in and around Marojejy National Park across a range of habitat types including villages, agricultural fields, regrowth areas, and secondary and semi-intact forests. Animals sampled included endemic tenrecs (Tenrecidae), rodents (Nesomyidae) and bats (6 families), along with non-native rodents (Muridae) and shrews (Soricidae). A hantavirus closely related to the previously described Anjozorobe virus infected 9.5% of Rattus rattus sampled. We did not detect hantaviruses in any other species. Habitat degradation had a complex impact on hantavirus prevalence in our study system: more intensive land use increase the abundance of R. rattus. The average body size of individuals varied between agricultural and nonagricultural land-use types, which in turn affected infection prevalence. Smaller R.rattus had lower probability of infection and were captured more commonly in villages and forests. Thus, infection prevalence was highest in agricultural areas. These findings provide new insights to the gradients of hantavirus exposure risk for humans in areas undergoing rapid land use transformations associated with agricultural practices.

6.
Ecol Evol ; 12(12): e9566, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36479032

RESUMEN

Cryptic species diversity is known to be common in bats but remains challenging to study in these mammals, whose natural history traits render their sampling and monitoring challenging. For these animals, indirect genetic approaches provide a powerful tool to gain insight into the evolutionary history and ecology of cryptic bat species. The speciation history of the polyphyletic Chaerephon pumilus species group (Molossidae) is poorly understood, including those found on western Indian Ocean islands. Two species in this complex have been identified in the Comoros: C. pusillus and C. leucogaster. Here, we aim to genetically characterize these two species and investigate their spatial population genetic structure. Analyzing five nuclear microsatellite markers from 200 individuals and one mitochondrial DNA gene (Cyt-b) from 161 (out of the 200) individuals sampled on Madagascar and the Comoros, our findings indicated that these species are genetically differentiated. We observed mitonuclear discordance in numerous individuals (33% of the 161 mtDNA-sequenced individuals). Based on ABC analyses, we found that this pattern could potentially be the result of asymmetric introgressive hybridization from C. leucogaster to C. pusillus and calls for further studies on the demographic history of these species. Moreover, at the intra-specific level, analyses of the microsatellite loci suggested the evidence of a more pronounced, although weak, geographically based genetic structure in C. pusillus than in C. leucogaster. Altogether, our findings provide preliminary insights into the eco-evolutionary aspects of this species complex and warrant further research to understand hybridization dynamics and mechanisms responsible for mitonuclear discordance.

7.
Science ; 378(6623): eabf0869, 2022 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-36454829

RESUMEN

Madagascar's biota is hyperdiverse and includes exceptional levels of endemicity. We review the current state of knowledge on Madagascar's past and current terrestrial and freshwater biodiversity by compiling and presenting comprehensive data on species diversity, endemism, and rates of species description and human uses, in addition to presenting an updated and simplified map of vegetation types. We report a substantial increase of records and species new to science in recent years; however, the diversity and evolution of many groups remain practically unknown (e.g., fungi and most invertebrates). Digitization efforts are increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge and identifying gaps in our understanding, particularly as species richness corresponds closely to collection effort. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. We highlight humid forests as centers of diversity and endemism because of their role as refugia and centers of recent and rapid radiations. However, the distinct endemism of other areas, such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest, is also biologically important despite lower species richness. The documented uses of Malagasy biodiversity are manifold, with much potential for the uncovering of new useful traits for food, medicine, and climate mitigation. The data presented here showcase Madagascar as a unique "living laboratory" for our understanding of evolution and the complex interactions between people and nature. The gathering and analysis of biodiversity data must continue and accelerate if we are to fully understand and safeguard this unique subset of Earth's biodiversity.


Asunto(s)
Biodiversidad , Evolución Biológica , Humanos , Biota , Bosques , Madagascar , Filogenia
8.
Science ; 378(6623): eadf1466, 2022 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-36454830

RESUMEN

Madagascar's unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar's terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.


Asunto(s)
Biodiversidad , Especies en Peligro de Extinción , Animales , Humanos , Teorema de Bayes , Biota , Madagascar , Mamíferos , Plantas
9.
Emerg. infect. dis. (Online) ; 28: 2583-2585, dez 12, 2022. mapa, tab
Artículo en Inglés | RSDM | ID: biblio-1532401

RESUMEN

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


Asunto(s)
Humanos , Animales , Ebolavirus/crecimiento & desarrollo , Ebolavirus/genética , Quirópteros , Ebolavirus/aislamiento & purificación , Mozambique/epidemiología
10.
Emerg Infect Dis ; 28(12): 2583-2585, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36418002

RESUMEN

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.


Asunto(s)
Quirópteros , Ebolavirus , Animales , Ebolavirus/genética , Mozambique/epidemiología , Guinea/epidemiología , Kenia
11.
Trop Med Infect Dis ; 7(8)2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-36006285

RESUMEN

Leptospirosis is a bacterial zoonosis caused by pathogenic Leptospira that are maintained in the kidney lumen of infected animals acting as reservoirs and contaminating the environment via infected urine. The investigation of leptospirosis through a One Health framework has been stimulated by notable genetic diversity of pathogenic Leptospira combined with a high infection prevalence in certain animal reservoirs. Studies of Madagascar's native mammal fauna have revealed a diversity of Leptospira with high levels of host-specificity. Native rodents, tenrecids, and bats shelter several distinct lineages and species of Leptospira, some of which have also been detected in acute human cases. Specifically, L. mayottensis, first discovered in humans on Mayotte, an island neighboring Madagascar, was subsequently identified in a few species of tenrecids on the latter island, which comprise an endemic family of small mammals. Distinct L. mayottensis lineages were identified in shrew tenrecs (Microgale cowani and Nesogale dobsoni) on Madagascar, and later in an introduced population of spiny tenrecs (Tenrec ecaudatus) on Mayotte. These findings suggest that L. mayottensis (i) has co-radiated with tenrecids on Madagascar, and (ii) has recently emerged in human populations on Mayotte following the introduction of T. ecaudatus from Madagascar. Hitherto, L. mayottensis has not been detected in spiny tenrecs on Madagascar. In the present study, we broaden the investigation of Malagasy tenrecids and test the emergence of L. mayottensis in humans as a result of the introduction of T. ecaudatus on Mayotte. We screened by PCR 55 tenrecid samples from Madagascar, including kidney tissues from 24 individual T. ecaudatus. We describe the presence of L. mayottensis in Malagasy T. ecaudatus in agreement with the aforementioned hypothesis, as well as in M. thomasi, a tenrecid species that has not been explored thus far for Leptospira carriage.

12.
Nat Commun ; 13(1): 2399, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35504912

RESUMEN

The distribution of the black rat (Rattus rattus) has been heavily influenced by its association with humans. The dispersal history of this non-native commensal rodent across Europe, however, remains poorly understood, and different introductions may have occurred during the Roman and medieval periods. Here, in order to reconstruct the population history of European black rats, we first generate a de novo genome assembly of the black rat. We then sequence 67 ancient and three modern black rat mitogenomes, and 36 ancient and three modern nuclear genomes from archaeological sites spanning the 1st-17th centuries CE in Europe and North Africa. Analyses of our newly reported sequences, together with published mitochondrial DNA sequences, confirm that black rats were introduced into the Mediterranean and Europe from Southwest Asia. Genomic analyses of the ancient rats reveal a population turnover in temperate Europe between the 6th and 10th centuries CE, coincident with an archaeologically attested decline in the black rat population. The near disappearance and re-emergence of black rats in Europe may have been the result of the breakdown of the Roman Empire, the First Plague Pandemic, and/or post-Roman climatic cooling.


Asunto(s)
Peste , Animales , Arqueología , ADN Mitocondrial/genética , Europa (Continente)/epidemiología , Humanos , Medio Oriente , Peste/epidemiología , Ratas
13.
Acta Trop ; 231: 106462, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35421381

RESUMEN

The Old World tropical and subtropical frugivorous bat genus Rousettus (Pteropodidae) contains species with broad distributions, as well as those occurring in restricted geographical areas, particularly islands. Herein we review the role of Rousettus as a keystone species from a global "One Health" approach and related to ecosystem functioning, zoonotic disease and public health. Rousettus are efficient at dispersing seeds and pollinating flowers; their role in forest regeneration is related to their ability to fly considerable distances during nightly foraging bouts and their relatively small body size, which allows them to access fruits in forested areas with closed vegetation. Rousettus are also reservoirs for various groups of pathogens (viruses, bacteria, fungi, protozoa), which, by definition, are infectious agents causing disease. The study of day roosts of different species of Rousettus and the successful establishment of captive breeding colonies have provided important details related to the infection dynamics of their associated pathogens. Large-scale conversion of forested areas into agricultural landscapes has increased contact between humans and Rousettus, therefore augmenting the chances of infectious agent spillover. Many crucial scientific details are still lacking related to members of this genus, which have direct bearing on the prevention of emerging disease outbreaks, as well as the conservation of these bats. The public should be better informed on the capacity of fruit bats as keystone species for large scale forest regeneration and in spreading pathogens. Precise details on the transmission of zoonotic diseases of public health importance associated with Rousettus should be given high priority.


Asunto(s)
Quirópteros , Animales , Ecosistema , Bosques , Humanos , Fitomejoramiento , Zoonosis
14.
PLoS One ; 17(2): e0263045, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35120158

RESUMEN

Madagascar is a large island to the south-east of Africa and in many ways continental in size and ecological complexity. Here we aim to define how skull morphology of an endemic and monophyletic clade of rodents (sub-family Nesomyinae), that show considerable morphological variation, have evolved and how their disparity is characterized in context of the geographical and ecological complexity of the island. We performed a two-dimensional geometric morphometric analysis on 370 dorsal and 399 ventral skull images of 19 species (comprising all nine extant endemic genera) and tested the influence of three ecological parameters (climate, locomotor habitat and nychthemeral cycle) in a phylogenetic context on size and shape. The results indicate that skull shape appears to importantly reflect phylogeny, whereas skull size does not carry a significant phylogenetic signal. Skull shape is significantly influenced by climate while, skull size is not impacted by any of the ecological factors tested, which is controversial to expectations in an insular context. In conclusion, Nesomyinae must have evolved under unusual types of local constraints, preventing this radiation from demonstrating strong ecological release.


Asunto(s)
Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Migración Animal , Animales , Evolución Biológica , Clima , Ecología , Geografía , Cabeza , Madagascar , Muridae , Filogenia , Especificidad de la Especie
15.
Bull Soc Zool Fr ; 147(3): 129-141, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37041752

RESUMEN

De par sa haute capacité d'adaptation et la plasticité de son alimentation, reflétée par une variation morphologique des individus, Rattus rattus s'est dispersé et a occupé un large éventail d'habitats à Madagascar après son introduction qui date du Xe siècle environ. Cette étude s'intéresse à la variation morphologique de cette espèce superposée à différents modes d'utilisation du paysage. Nous avons analysé des données morphométriques crânio-dentaires recueillies à partir de 333 spécimens capturés dans le bassin-versant de la rivière Manantenina sur la partie orientale du Massif de Marojejy. Les résultats des tests MANOVA comparant la morphologie crânio-dentaire et la taille des individus par sexe, classe d'âge et type d'habitat ont montré qu'il existe des différences significatives entre la forme du crâne et la taille des individus parmi les types d'habitat et la classe d'âge. Aucun dimorphisme sexuel n'a été trouvé sur la morphologie du crâne, par contre la taille des mâles est significativement plus grande par rapport à celle des femelles. Les individus vivant en dehors de l'habitat forestier ont des crânes nettement plus gros (Tukey HSD, p = 0,004). Comme anticipé, les jeunes individus ont un crâne plus petit que les adultes et les adultes plus âgés, mais la largeur de leur première molaire, la longueur de la rangée de dents de la mandibule et la longueur de la couronne de la rangée de molaire maxillaire sont plus grandes. Due to their high adaptability and dietary plasticity, reflected by individual morphological variation, Rattus rattus has dispersed to and occupies a broad range of habitats on Madagascar after its introduction to the island, which dates towards the 10th century. This study focuses on morphological variation of this species overlaid on different human land use patterns.We analyzed cranio-dental morphometric data collected from 333 specimens captured in the Manantenina River valley on the eastern side of the Marojejy Massif.The results of the MANOVA tests comparing cranio-dental morphology and size of individuals by sex, age class, and habitat type showed that there are significant differences between skull shape and size of individuals among the habitat types and age classes. No sexual dimorphism based on cranio-dental morphology was found but we noted a significant difference between male and female body size between different habitats. Individuals living outside of native forest have distinctly larger skulls (Tukey HSD, p = 0,004). As anticipated, young individuals have a smaller skull than adults and old adults, however the breadth of their first molar, length of mandible toothrow, and crown length of maxillary molar row are proportionally larger.

16.
Trop Med Infect Dis ; 6(4)2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34941661

RESUMEN

Leptospirosis is the most prevalent bacterial zoonosis worldwide and, in this context, has been extensively investigated through the One Health framework. Diagnosis of human leptospirosis includes molecular and serological tools, with the serological Microscopic Agglutination Test (MAT) still being considered as the gold standard. Mammals acting as reservoirs of the pathogen include species or populations that are able to maintain chronic infection and shed the bacteria via their urine into the environment. Animals infected by Leptospira are often identified using the same diagnosis tool as in humans, i.e., serological MAT. However, this tool may lead to misinterpretations as it can signal previous infection but does not provide accurate information regarding the capacity of animals to maintain chronic infection and, hence, participate in the transmission cycle. We employ in this paper previously published data and present original results on introduced and endemic small mammals from Indian Ocean islands to show that MAT should not be used for the identification of Leptospira reservoirs. By contrast, serological data are informative on the level of exposure of animals living in a specific environment. We present a sequential methodology to investigate human leptospirosis in the One Health framework that associates molecular detection in humans and animals, together with MAT of human samples using Leptospira isolates obtained from reservoir animals occurring in the same environment.

17.
Virol J ; 18(1): 205, 2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34641936

RESUMEN

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.


Asunto(s)
Infecciones por Astroviridae/epidemiología , Quirópteros/virología , Coinfección/epidemiología , Infecciones por Coronavirus/epidemiología , Infecciones por Paramyxoviridae/epidemiología , Animales , Madagascar , Mozambique , Reunión
18.
Malar J ; 20(1): 157, 2021 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-33743716

RESUMEN

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.


Asunto(s)
Quirópteros , Haemosporida/fisiología , Interacciones Huésped-Parásitos , Infecciones Protozoarias en Animales/epidemiología , Animales , Madagascar/epidemiología , Filogenia , Prevalencia , Infecciones Protozoarias en Animales/clasificación , Infecciones Protozoarias en Animales/parasitología , Análisis de Secuencia de ADN/veterinaria
20.
PLoS One ; 16(2): e0240770, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33591975

RESUMEN

The order Carnivora, which currently includes 296 species classified into 16 families, is distributed across all continents. The phylogeny and the timing of diversification of members of the order are still a matter of debate. Here, complete mitochondrial genomes were analysed to reconstruct the phylogenetic relationships and to estimate divergence times among species of Carnivora. We assembled 51 new mitogenomes from 13 families, and aligned them with available mitogenomes by selecting only those showing more than 1% of nucleotide divergence and excluding those suspected to be of low-quality or from misidentified taxa. Our final alignment included 220 taxa representing 2,442 mitogenomes. Our analyses led to a robust resolution of suprafamilial and intrafamilial relationships. We identified 21 fossil calibration points to estimate a molecular timescale for carnivorans. According to our divergence time estimates, crown carnivorans appeared during or just after the Early Eocene Climatic Optimum; all major groups of Caniformia (Cynoidea/Arctoidea; Ursidae; Musteloidea/Pinnipedia) diverged from each other during the Eocene, while all major groups of Feliformia (Nandiniidae; Feloidea; Viverroidea) diversified more recently during the Oligocene, with a basal divergence of Nandinia at the Eocene/Oligocene transition; intrafamilial divergences occurred during the Miocene, except for the Procyonidae, as Potos separated from other genera during the Oligocene.


Asunto(s)
Carnívoros/clasificación , Carnívoros/genética , Genoma Mitocondrial/genética , Animales , Evolución Biológica , ADN Mitocondrial/genética , Evolución Molecular , Fósiles , Variación Genética/genética , Filogenia , Análisis de Secuencia de ADN/métodos
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