Independent gene phylogenies and morphology demonstrate a malagasy origin for a wide-ranging group of swallowtail butterflies

Madagascar is home to numerous endemic species and lineages, but the processes that have contributed to its endangered diversity are still poorly understood. Evidence is accumulating to demonstrate the importance of Tertiary dispersal across varying distances of oceanic barriers, supplementing vicariance relationships dating back to the Cretaceous, but these hypotheses remain tentative in the absence of well-supported phylogenies. In the Papilio demoleus group of swallowtail butterflies, three of the five recognized species are restricted to Madagascar, whereas the remaining two species range across the Afrotropical zone and southern Asia plus Australia. We reconstructed phylogenetic relationships for all species in the P. demoleus group, as well as 11 outgroup Papilio species, using 60 morphological characters and about 4 kb of nucleotide sequences from two mitochondrial (cytochrome oxidase I and II) and two nuclear (wg and EF-1alpha) genes. Of the three endemic Malagasy species, the two that are formally listed as endangered or at risk represented the most basal divergences in the group, while the more common third endemic was clearly related to African P. demodocus. The fifth species, P. demoleus, showed little differentiation across southern Asia, but showed divergence from its subspecies sthenelus in Australia. Dispersal-vicariance analysis using cladograms derived from morphology and three independent genes indicated a Malagasy diversification of lime swallowtails in the middle Miocene. Thus, diversification processes on the island of Madagascar may have contributed to the origin of common butterflies that now occur throughout much of the Old World tropical and subtemperate regions. An alternative hypothesis, that Madagascar is a refuge for ancient lineages resulting from successive colonizations from Africa, is less parsimonious and does not explain the relatively low continental diversity of the group.     

Contrasting patterns of diversification in a bird family (Aves: Gruiformes: Rallidae) are revealed by analysis of geospatial distribution of species and phylogenetic diversity

Geospatial patterns in the distribution of regional biodiversity reflect the composite processes that underpin evolution: speciation, dispersal and extinction. The spatial distribution and phylogeny of a globally widespread and species rich bird family (Rallidae) were used to help assess the role of large‐scale biogeographical processes in diversity and diversification. Here, we examine how different geostatistical diversity metrics enhance our understanding of species distribution by linking occurrence records of rail species to corresponding species level phylogeny. Tropical regions and temperate zones contained a large proportion of rail species richness and phylogenetic diversity whilst small islands in Australian, Oceanian and Oriental regions held the highest weighted and phylogenetic endemism. Our results suggest that habitat connectivity and dispersal were important ecological features in rail evolution and distribution. Spatial isolation was a significant driver of diversification where islands in Oceania were centres of neo‐endemism with recent multiple and independent speciation events and could be considered as nurseries of biodiversity. Palaeo‐endemism was mostly associated with older stable regions, so despite extensive long distance range shifting these areas retain their own ancient and distinct character. Madagascar was the major area of palaeo‐endemism associated with the oldest rail lineages and could be considered a museum of rail diversity. This implies a mixture of processes determine the current distribution and diversity of rail clades with some areas dominated by recent ‘in situ’ speciation while others harbour old diversity with ecological traits that have stood the test of time.     

Molecular evolution and radiation of dung beetles in Madagascar

Madagascar is the world's fourth largest island and has a wide range of climates and ecosystems. Environmental diversity combined with long history of isolation (160 Myr) has generated a high level of endemism at different taxonomic levels, making Madagascar one of the hotspots of global biodiversity. Dung beetles, represented by the two tribes of Canthonini and Helictopleurini, exemplify a large insect taxon. Helictopleurini are completely endemic to Madagascar while Canthonini are endemic at generic level. Using data from mitochondrial and nuclear genes, phylogenetic relationships were investigated in a sample of 44 species. The phylogeny for Canthonini consists of several distinct clades, possibly reflecting multiple colonization of Madagascar. The phylogeny does not support the current taxonomy for all genera. The phylogeny for Helictopleurini lacks statistical support at supra‐specific level, and genetic divergence among the Helictopleurini species is comparable with that among species within genera in Canthonini. These results suggest that Helictopleurini has undergone rapid speciation and most likely more recently than Canthonini, consistent with the estimated radiation time based on mtDNA mutation rates in insects and with knowledge about the systematics and geographic distribution of dung beetles worldwide. A detailed analysis of sequence composition identified common patterns in Malagasy dung beetles and other insects. © The Willi Hennig Society 2007.     

Freshwater mussel (Mollusca: Bivalvia: Unionoida) richness and endemism in the ecoregions of Africa and Madagascar based on comprehensive museum sampling

The objective of this study was to assess freshwater mussel (Mollusca: Bivalvia: Unionoida) species distributions among the freshwater ecoregions of Africa and Madagascar to discover areas of high richness and endemism. These are among the top criteria for identifying biodiversity hotspots and establishing conservation priorities. Distributions were determined from museum specimens in 17 collections. In total, 5,612 records for 87 unionoid species could each be assigned to one of 90 freshwater ecoregions. The majority of species (55%) are known from only one (34 spp.) or two (14) ecoregions. Only three are known from more than 20 ecoregions: Etheria elliptica (38 ecoregions), Chambardia wahlbergi (25), and Mutela rostrata (21). The most species-rich ecoregions are Lake Victoria Basin (17 spp.), Upper Nile (16), Upper Congo (14), Senegal–Gambia (13), and Sudanic Congo–Oubangi (13). Those with the most endemic species are Lake Tanganyika (8 spp.), Lake Victoria Basin (6), Bangweulu–Mweru (4), and Lake Malawi (3). Twenty-five ecoregions have no known freshwater mussels. These patterns are significantly correlated with fish and general freshwater mollusk richness. Unionoid richness also varies significantly among major habitat types. These patterns are relevant to biogeography and conservation and indicate areas in need of further research. We argue that freshwater mussels are valuable as focal species for conservation assessments, and they themselves merit management consideration for their ecosystem functions and distributions in imperiled habitats. It is recommended that field surveys be conducted to determine the current status of species in all areas of Africa and Madagascar.     

Amazonian biodiversity: assessing conservation priorities with taxonomic data

Data from 3991 records of museum collections representing 421 species of plants, arthropods, amphibians, fish, and primates were analyzed with GIS to identify areas of high species diversity and endemism in Amazonia. Of the 472 1 × 1° grid cells in Amazonia, only nine cells are included in the highest species diversity category (43–67 total species) and nine in the highest endemic species diversity category (4–13 endemic species). Over one quarter of the grid cells have no museum records of any of the organisms in our study. Little correspondence exists between the centers of species diversity identified by our collections-based data and those areas recommended for conservation in an earlier qualitative study of Amazonian biodiversity. Museum collections can play a vital role in identifying species-rich areas for potential conservation in Amazonia, but a concerted and structured effort to increase the number and distribution of collections is needed to take maximum advantage of the information they contain.     

Phylogenetic position of African and Malagasy Pimpinella species and related genera (Apiaceae, Pimpinelleae)

The phylogenetic position of the African and Malagasy species of Pimpinella is assessed using nrDNA ITS sequence data and a representative sampling of the genus, including 16 species from Africa and Madagascar and 26 species from Eurasia. The results of maximum parsimony and Bayesian analyses of these data show that the African and Malagasy species ally with their Eurasian counterparts in Pimpinelleae. The genus Pimpinella is rendered paraphyletic by the inclusion of African Cryptotaenia and the small African and Malagasy endemic genera Frommia and Phellolophium. Within a paraphyletic Pimpinella, three major clades are recovered, with the African species occupying two of these clades. The current sectional classification of the genus, based predominantly on fruit vestiture, is largely artificial. Chromosome base number, however, was found to be consistent with the groupings recovered in the molecular analyses. Those African and Malagasy Pimpinella species with a chromosome base number of x = 11 and largely glabrous petals and fruits, form the earliest diverging clade together with Frommia, which also has a base count of n = 11 and glabrous petals and fruits. The remaining African species ally with several Eurasian species of Pimpinella and share a chromosome base number of x = 9 and usually hairy petals and fruits.     

Tenrec phylogeny and the noninvasive extraction of nuclear DNA

Due in part to scarcity of material, no published study has yet cladistically addressed the systematics of living and fossil Tenrecidae (Mammalia, Afrotheria). Using a noninvasive technique for sampling nuclear DNA from museum specimens, we investigate the evolution of the Tenrecidae and assess the extent to which tenrecids fit patterns of relationships proposed for other terrestrial mammals on Madagascar. Application of several tree-reconstruction techniques on sequences of the nuclear growth hormone receptor gene and morphological data for all recognized tenrecid genera supports monophyly of Malagasy tenrecids to the exclusion of the two living African genera. However, both parsimony and Bayesian methods favor a close relationship between fossil African tenrecs and the Malagasy Geogale, supporting the hypothesis of island paraphyly, but not polyphyly. More generally, the noninvasive extraction technique can be applied with minimal risk to rare/unique specimens and, by better utilizing museum collections for genetic work, can greatly mitigate field expenses and disturbance of natural populations.     

Conservation biology of Malagasy strepsirhines: a phylogenetic approach

The phylogenetic diversity of extant lemurs represents one of the most important but least studied aspects of the conservation biology of primates. The phylogenetic diversity of a species is inversely proportional to the relative number and closeness of its phylogenetic relatives. Phylogenetic diversity can then be used to determine conservation priorities for specific biogeographic regions. Although Malagasy strepsirhines represent the highest phylogenetic diversity among primates at the global level, there are few phylogenetic data on species-specific and regional conservation plans for lemurs in Madagascar. Therefore, in this paper the following questions are addressed for extant lemurs: 1) how does the measure of taxonomic uniqueness used by Mittermeier et al. (1992 Lemurs of Madagascar; Gland, Switzerland: IUCN) equate with an index of phylogenetic diversity, 2) what are the regional conservation priorities based on analyses of phylogenetic diversity in extant lemurs, and 3) what conservation recommendations can be made based on analyses of phylogenetic diversity in lemurs? Taxonomic endemicity standardized weight (TESW) indices of phylogenetic diversity were used to determine the evolutionary component of biodiversity and to prioritize regions for conserving lemur taxa. TESW refers to the standardization of phylogenetic diversity indices for widespread taxa and endemicity of species. The phylogenetic data came from recent genetic studies of Malagasy strepsirhines at the species level. Lemur species were assigned as being either present or absent in six biogeographic regions. TESW indices were combined with data on lemur complementarity and protected areas to assign conservation priorities at the regional level. Although there were no overall differences between taxonomic ranks and phylogenetic rankings, there were significant differences for the top-ranked taxa. The phylogenetic component of lemur diversity is greatest for Daubentonia madagascariensis, Allocebus trichotis, Lepilemur septentrionalis, Indri indri, and Mirza coquereli. Regional conservation priorities are highest for lemurs that range into northeast humid forests and western dry forests. Expansion of existing protected areas in these regions may provide the most rapid method for preserving lemurs. In the long term, new protected areas must be created because there are lemur species that: 1) are not found in existing protected areas, 2) exist only in one or two protected areas, and 3) are still being discovered outside the current network of protected areas. Data on the population dynamics and feeding ecology of phylogenetically important species are needed to ensure that protected areas adequately conserve lemur populations in Madagascar.     

An endemic radiation of Malagasy songbirds is revealed by mitochondrial DNA sequence data

The bird fauna of Madagascar includes a high proportion of endemic species, particularly among passerine birds (Aves: Passeriformes). The endemic genera of Malagasy songbirds are not allied obviously with any African or Asiatic taxa, and their affinities have been debated since the birds first were described. We used mitochondrial sequence data to estimate the relationships of 13 species of endemic Malagasy songbirds, 17 additional songbird species, and one species of suboscine passerine. In our optimal trees, nine of the 13 Malagasy species form a clade. although these birds currently are classified in three different families. In all optimal trees, the sister to this endemic clade is a group of Old World warblers including both African and Malagasy birds. The endemic Malagasy songbird clade rivals other island radiations, including the vangas of Madagascar and the finches of the Galapagos, in ecological diversity.     

Shifting continents, not behaviours: independent colonization of solitary and subsocial Anelosimus spider lineages on Madagascar (Araneae, Theridiidae)

Agnarsson, I., Kuntner, M., Coddington, J. A. & Blackledge, T. A. (2009). Shifting continents, not behaviours: independent colonization of solitary and subsocial Anelosimus spider lineages on Madagascar (Araneae, Theridiidae). —Zoologica Scripta, 39, 75–87. Madagascar is a biodiversity hotspot, thought to be colonized mostly via Cenozoic dispersal from Africa, followed by endemic radiation of multiple lineages. Anelosimus spiders are diverse in Madagascar, and, like their congeners in the Americas, are most diverse in wet montane forests. Most Anelosimus species are social in that they cooperate in web building and prey capture either during a part of their life cycles (subsocial), including hitherto studied Malagasy species, or permanently (quasisocial). One Central American coastal species, Anelosimus pacificus, has secondarily switched to solitary living, and available evidence suggests that its closest relatives from S. America and Europe are likely also solitary. Here, we show that the only known coastal Anelosimus species in Madagascar and Comoros –Anelosimus decaryi and Anelosimus amelie sp. n. – are also solitary. Using a phylogenetic approach, we test two competing hypotheses: (i) that Malagasy Anelosimus are monophyletic and thus represent a second example of reversal to solitary living in a littoral habitat or (ii) that solitary and subsocial lineages independently colonized Madagascar. We find that solitary Malagasy Anelosimus are closely related to their solitary counterparts from Europe and the Americas, while subsocial Malagasy species nest sister to Anelosimus nelsoni from S. Africa. This finding suggests that (i) the two Anelosimus lineages colonized Madagascar independently and (ii) a reversal to solitary behaviour has occurred only once in Anelosimus. Thus, solitary littoral Malagasy species did not descend from Malagasy mountains, but arrived from much further afar. African and possibly American origin of the two lineages is implied by our findings. To restore natural classification of Anelosimus, Seycellocesa Koçak & Kemal is synonymized with it.     

Weak divergence among African, Malagasy and Seychellois hinged terrapins (Pelusios castanoides, P. subniger) and evidence for human-mediated oversea dispersal

Using phylogenetic and haplotype network analyses of 2036 bp of mitochondrial DNA, we compare samples of the two hinged terrapin species Pelusios castanoides and P. subniger from continental Africa, Madagascar and the Seychelles to infer their biogeography. Owing to the long independent history of Madagascar and the Seychelles, the populations from those islands should be deeply divergent from their African conspecifics. Seychellois populations of the two species are currently recognized as Critically Endangered endemic subspecies. However, even though we found within P. subniger evidence for a cryptic species from the Democratic Republic of the Congo, all other samples assigned to this species were undifferentiated. This suggests that Malagasy and Seychellois populations of P. subniger were introduced by humans and that the Seychellois subspecies P. s. parietalis is invalid. This has implications for current conservation strategies for the Critically Endangered Seychellois populations and suggests that measures should rather focus on endemic species. The situation of P. castanoides could be different. Samples from Madagascar and the Seychelles are weakly, but consistently, differentiated from continental African samples, and Malagasy and Seychellois samples are reciprocally monophyletic in maximum likelihood analyses. However, due to a lack of samples from central and northern Mozambique and Tanzania, we cannot exclude that identical continental haplotypes exist there.     

Molecular phylogeny,biogeography and chromosome evolution of Malagasy dwarf geckos of the genus Lygodactylus (Squamata,Gekkonidae)

We performed a phylogenetic analysis using nuclear (RAG‐1, RAG‐2) and mitochondrial (16S) markers, a statistical Bayesian reconstruction of ancestral distribution areas and a karyological analysis on most Malagasy species of the gekkonid genus Lygodactylus. The phylogenetic analysis largely confirms major basal branching pattern of previous molecular studies, but highlights significant differences concerning both the relationships between different species groups as well as those within groups. The biogeographic analysis supports a Malagasy origin of Lygodactylus, an oversea dispersal to continental Africa and a return to Madagascar. The L. madagascariensis group (also including a new candidate species identified herein) is the most basal clade in Lygodactylus, and the sister group of a clade with all the remaining species. The second most basal clade is the L. verticillatus group, placed as the sister group of a clade comprising African and Malagasy species. The sister lineage of the L. verticillatus group originated the African radiation through an oversea dispersal out of Madagascar. Eventually, the sister lineage of the L. capensis group originated secondary dispersals from Africa to Madagascar. In Madagascar, lineage diversification in different species groups mainly occurred from southern to northern and eastern regions. Dispersal, vicariance and paleoclimatic refugia probably played a relevant role in the evolutionary history of closely related taxa and in speciation mechanisms. The cytogenetic analysis evidenced a high karyotypic variability in Lygodactylus (from 2n = 34 to 2n = 40), which is at least partly consistent with the phylogenetic relationships and the composition of the various species group. Chromosome evolution occurred independently in different lineages, mainly through a reduction in the chromosome number and starting from a putative primitive karyotype of 2n = 40 with all telocentric elements.     

First data on the molecular phylogeography of scincid lizards of the genus Mabuya

A 487-bp fragment of the mitochondrial 16S rRNA gene was sequenced in 26 species of the circumtropical lizard genus Mabuya and used to analyze phylogenetic relationships within the genus. The species from Africa and Madagascar formed a monophyletic group relative to the included Asian and South American taxa. The Malagasy species included (M. elegans, M. cf. dumasi, and M. comorensis) did not appear as a monophylum. Combined and separate analysis of the 16S data and additional sequences of the mitochondrial 12S rRNA, ND4, and cytochrome b genes (a total of 2255 bp) in one Asian, two Malagasy, and two African species also did not result consistently in a monophyletic grouping of the Malagasy taxa. However, a monophylum containing African and Malagasy taxa was strongly supported by the combined analysis. These preliminary results indicate that Mabuya probably colonized Madagascar from Africa through the Mozambique Channel.     

The dual origin of the Malagasy in Island Southeast Asia and East Africa: evidence from maternal and paternal lineages

Linguistic and archaeological evidence about the origins of the Malagasy, the indigenous peoples of Madagascar, points to mixed African and Indonesian ancestry. By contrast, genetic evidence about the origins of the Malagasy has hitherto remained partial and imprecise. We defined 26 Y-chromosomal lineages by typing 44 Y-chromosomal polymorphisms in 362 males from four different ethnic groups from Madagascar and 10 potential ancestral populations in Island Southeast Asia and the Pacific. We also compared mitochondrial sequence diversity in the Malagasy with a manually curated database of 19,371 hypervariable segment I sequences, incorporating both published and unpublished data. We could attribute every maternal and paternal lineage found in the Malagasy to a likely geographic origin. Here, we demonstrate approximately equal African and Indonesian contributions to both paternal and maternal Malagasy lineages. The most likely origin of the Asia-derived paternal lineages found in the Malagasy is Borneo. This agrees strikingly with the linguistic evidence that the languages spoken around the Barito River in southern Borneo are the closest extant relatives of Malagasy languages. As a result of their equally balanced admixed ancestry, the Malagasy may represent an ideal population in which to identify loci underlying complex traits of both anthropological and medical interest.     

Spatial patterns of phylogenetic diversity and endemism in the Western Ghats,India: A case study using ancient predatory arthropods

The Western Ghats (WG) mountain chain in peninsular India is a global biodiversity hotspot, one in which patterns of phylogenetic diversity and endemism remain to be documented across taxa. We used a well‐characterized community of ancient soil predatory arthropods from the WG to understand diversity gradients, identify hotspots of endemism and conservation importance, and highlight poorly studied areas with unique biodiversity. We compiled an occurrence dataset for 19 species of scolopendrid centipedes, which was used to predict areas of habitat suitability using bioclimatic and geomorphological variables in Maxent. We used predicted distributions and a time‐calibrated species phylogeny to calculate taxonomic and phylogenetic indices of diversity, endemism, and turnover. We observed a decreasing latitudinal gradient in taxonomic and phylogenetic diversity in the WG, which supports expectations from the latitudinal diversity gradient. The southern WG had the highest phylogenetic diversity and endemism, and was represented by lineages with long branch lengths as observed from relative phylogenetic diversity/endemism. These results indicate the persistence of lineages over evolutionary time in the southern WG and are consistent with predictions from the southern WG refuge hypothesis. The northern WG, despite having low phylogenetic diversity, had high values of phylogenetic endemism represented by distinct lineages as inferred from relative phylogenetic endemism. The distinct endemic lineages in this subregion might be adapted to life in lateritic plateaus characterized by poor soil conditions and high seasonality. Sites across an important biogeographic break, the Palghat Gap, broadly grouped separately in comparisons of species turnover along the WG. The southern WG and Nilgiris, adjoining the Palghat Gap, harbor unique centipede communities, where the causal role of climate or dispersal barriers in shaping diversity remains to be investigated. Our results highlight the need to use phylogeny and distribution data while assessing diversity and endemism patterns in the WG.     

In or Out-of-Madagascar?—Colonization Patterns for Large-Bodied Diving Beetles (Coleoptera: Dytiscidae)

High species diversity and endemism within Madagascar is mainly the result of species radiations following colonization from nearby continents or islands. Most of the endemic taxa are thought to be descendants of a single or small number of colonizers that arrived from Africa sometime during the Cenozoic and gave rise to highly diverse groups. This pattern is largely based on vertebrates and a small number of invertebrate groups. Knowledge of the evolutionary history of aquatic beetles on Madagascar is lacking, even though this species-rich group is often a dominant part of invertebrate freshwater communities in both standing and running water. Here we focus on large bodied diving beetles of the tribes Hydaticini and Cybistrini. Our aims with this study were to answer the following questions 1) How many colonization events does the present Malagasy fauna originate from? 2) Did any colonization event lead to a species radiation? 3) Where did the colonizers come from—Africa or Asia—and has there been any out-of-Madagascar event? 4) When did these events occur and were they concentrated to any particular time interval? Our results suggest that neither in Hydaticini nor in Cybistrini was there a single case of two or more endemic species forming a monophyletic group. The biogeographical analysis indicated different colonization histories for the two tribes. Cybistrini required at least eight separate colonization events, including the non-endemic species, all comparatively recent except the only lotic (running water) living Cybister operosus with an inferred colonization at 29 Ma. In Hydaticini the Madagascan endemics were spread out across the tree, often occupying basal positions in different species groups. The biogeographical analyses therefore postulated the very bold hypothesis of a Madagascan origin at a very deep basal node within Hydaticus and multiple out-of-Madagascar dispersal events. This hypothesis needs to be tested with equally intense taxon sampling of mainland Africa as for Madagascar.     

Integrative taxonomy and phylogeny of leafless Vanilla orchids from the South-West Indian Ocean region reveal two new Malagasy species

The leafless Vanilla species complex from the South-West Indian Ocean (SWIO) region has long been a taxonomic challenge, due to limited patterns of morphological differentiation and an absence of variation within chloroplast sequences. This complex includes seven known morphospecies: V. madagascariensis, V. bosseri, V. decaryana, and V. perrieri endemic to Madagascar, V. humblotii presumed as endemic to the Comoros Archipelago, but also present in Madagascar, V. roscheri from the East African coast, and V. phalaenopsis endemic to Seychelles. A previous population genetic study using microsatellite markers allowed us to distinguish, in addition to the five recognized Malagasy taxa, two other genetic clusters present in the East of the island. An integrative taxonomy approach was therefore conducted by combining microsatellite and morphological data used in the previous study with new data sets, and by adding ITS sequencing data, to validate the taxonomic level of these Malagasy genetic clusters and unravel phylogenetic relationships between SWIO species. As a result, based on phylogenetic, genotypic and morphological evidence, nine species were discriminated in the SWIO region, including seven in Madagascar, with two new eastern species. The leafless Vanilla group originated and diversified in Madagascar, from an ancestor of African descent, with three subsequent independent colonization events from Madagascar to the other territories of SWIO within the two main lineages (white versus yellow flower species). The new Malagasy species, V. allorgeae Andriamihaja & Pailler sp. nov., and V. atsinananensis Andriamihaja & Pailler sp. nov., are described and a new identification key is proposed.     

DNA-based fungal diversity in Madagascar and arrival of the ectomycorrhizal fungi to the island

Madagascar is known for its high diversity and endemism of fauna and flora. Fungi, however, have been largely overlooked in diversity and evolution studies on the island, and whether fungi exhibit the same patterns as animals and plants has yet to be further examined. We collected fungal sporocarps and ectomycorrhizal (EcM) roots during three opportunistic surveys in five forests in Madagascar and generated a dataset of fungal Internal Transcribed Spacer (ITS) DNA sequences. We analyzed them together with all publicly available fungal ITS DNA sequences and identified 620 Operational Taxonomic Units (OTUs) from Madagascar, 10% of which contained only sequences from our surveys. Two hundred and ninety-two OTUs belonged to EcM species with /russula-lactarius, /boletus, /tomentella-telephora, /cortinarius, and /amanita being the most abundant EcM lineages. Overall, 60% of all fungi and 81% of the EcM species from Madagascar appear to be endemic. We conducted a phylogenetic analysis using all the OTUs in Amanitaceae, Boletaceae, and Russulaceae families to elucidate their relative timing of arrival in Madagascar. We found that most EcM species from Madagascar in the three families diverged less than 22 million years ago (mya), long after the separation of India and Madagascar (88 mya), which is consistent with a dispersal mediated process of arrival to the island. Our study provides the first comprehensive view of the overall DNA-based fungal diversity in Madagascar and the current state of knowledge of EcM fungi based on DNA sequences, useful for further ecological and evolutionary studies. Abstract in Malagasy is available with online material.     

Diversification of an emerging pathogen in a biodiversity hotspot: Leptospira in endemic small mammals of Madagascar

Biodiversity hotspots and associated endemism are ideal systems for the study of parasite diversity within host communities. Here, we investigated the ecological and evolutionary forces acting on the diversification of an emerging bacterial pathogen, Leptospira spp., in communities of endemic Malagasy small mammals. We determined the infection rate with pathogenic Leptospira in 20 species of sympatric rodents (subfamily Nesomyinae) and tenrecids (family Tenrecidae) at two eastern humid forest localities. A multilocus genotyping analysis allowed the characterization of bacterial diversity within small mammals and gave insights into their genetic relationships with Leptospira infecting endemic Malagasy bats (family Miniopteridae and Vespertilionidae). We report for the first time the presence of pathogenic Leptospira in Malagasy endemic small mammals, with an overall prevalence of 13%. In addition, these hosts harbour species of Leptospira (L. kirschneri, L. borgpetersenii and L. borgpetersenii group B) which are different from those reported in introduced rats (L. interrogans) on Madagascar. The diversification of Leptospira on Madagascar can be traced millions of years into evolutionary history, resulting in the divergence of endemic lineages and strong host specificity. These observations are discussed in relation to the relative roles of endemic vs. introduced mammal species in the evolution and epidemiology of Leptospira on Madagascar, specifically how biodiversity and biogeographical processes can shape community ecology of an emerging pathogen and lead to its diversification within native animal communities.