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1.
Stingless bees (Meliponini) are one of only two highly eusocial bees, the other being the well studied honey bee (Apini). Unlike Apini, with only 11 species in the single genus Apis, stingless bees are a large and diverse taxon comprising some 60 genera, many of which are poorly known. This is the first attempt to infer a phylogeny of the group that includes the world fauna and extensive molecular data. Understanding the evolutionary relationships of these bees would provide a basis for behavioural studies within an evolutionary framework, illuminating the origins of complex social behaviour, such as the employment of dance and sound to communicate the location of food or shelter. In addition to a global phylogeny, we also provide estimates of divergence times and ancestral biogeograhic distributions of the major groups. Bayesian and maximum likelihood analyses strongly support a principal division of Meliponini into Old and New World groups, with the Afrotropical+Indo‐Malay/Australian clades comprising the sister group to the large Neotropical clade. The meliponine crown clade is inferred to be of late Gondwanan origin (approximately 80 Mya), undergoing radiations in the Afrotropical and Indo‐Malayan/Australasian regions, approximately 50–60 Mya. In the New World, major diversifications occurred approximately 30–40 Mya. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 206–232.  相似文献   

2.
Pyrgomatid barnacles are a family of balanomorphs uniquely adapted to symbiosis on corals. The evolution of the coral‐dwelling barnacles is explored using a multi‐gene phylogeny (COI, 16S, 12S, 18S, and H3) and phenotypic trait‐mapping. We found that the hydrocoral associate Wanella should be excluded, while some archaeobalanids in the genus Armatobalanus should be included in the Pyrgomatidae. Three well supported clades were recovered: clade I is the largest group and is exclusively Indo‐West Pacific, clade II contains two plesiomorphic Indo‐West Pacific genera, while clade III is comprised of East and West Atlantic taxa. Some genera did not form reciprocally monophyletic groups, while the genus Trevathana was found to be paraphyletic and to include members of three other apomorphic genera/tribes. The highly unusual coral‐parasitic hoekiines appear to be of recent origin and rapidly evolving from Trevathana sensu lato. Pyrgomatids include six‐, four‐, and one‐plated forms, and exhibit convergent evolutionary tendencies towards skeletal reduction and fusion, loss of cirral armature, and increased host specificity. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 162–179.  相似文献   

3.
Using multilocus DNA fingerprinting with phage M13 DNA as a probe, we have investigated a heterogeneous group of four human populations from Eastern Europe and Northeastern Asia. These populations belong to two language families: Indo-European (Eastern Slavonic branch: Russians, Belarussians) and Altaian (Turkic branch: Yakuts). The experimental results were treated by different statistical techniques: cluster analysis, multidimensional scaling, and multiple correspondence analysis. Coefficients of genetic differentiation were estimated using similarity indices and heterozygosities. The results of our study demonstrated similarity of Belarussian populations and significant differences between the group of Slavonic populations and Yakuts.  相似文献   

4.
Using multilocus DNA fingerprinting with phage M13 DNA as a probe, we have investigated a heterogeneous group of four human populations from Eastern Europe and Northeastern Asia. These populations belong to two language families: Indo-European (Eastern Slavonic branch: Russians, Belarussians) and Altaian (Turkic branch: Yakuts). The experimental results were treated by different statistical techniques: cluster analysis, multidimensional scaling, and multiple correspondence analysis. Coefficients of genetic differentiation were estimated using similarity indices and heterozygosities. The results of our study demonstrated similarity of Belarussian populations and significant differences between the group of Slavonic populations and Yakuts.  相似文献   

5.
Bilateral palmar prints of 604 male individuals from 12 Iranian groups, six Mongoloid and six Caucasoid, have been analyzed for palmar pattern ridge counts (PPRC). Highly significant variation has been observed in the size of the palmar patterns in all the configurational areas among the Iranian groups. The distance analysis based on PPRCs differentiated the Iranian Mongoloid from the Iranian Caucasoid groups into distinct clusters. The pattern of differentiation based on PPRCs explained the ethnohistoric relationships between the Iranian groups as well as between the Iranian and the 20 Caucasoid groups from India much better than the palmar pattern frequencies. The results of this study demonstrate the existence of variation in the size of the palmar patterns across different populations within an ethnic group, as well as that among different ethnic groups, and seems to be a better indicator of interpopulational diversity than the palmar pattern frequencies.  相似文献   

6.
The Indo‐Australian Archipelago (IAA) is the richest area of biodiversity in the marine realm, yet the processes that generate and maintain this diversity are poorly understood and have hardly been studied in the mangrove biotope. Cerithidea is a genus of marine and brackish‐water snails restricted to mangrove habitats in the Indo‐West Pacific, and its species are believed to have a short pelagic larval life. Using molecular and morphological techniques, we demonstrate the existence of 15 species, reconstruct their phylogeny and plot their geographical ranges. Sister species show a pattern of narrowly allopatric ranges across the IAA, with overlap only between clades that show evidence of ecological differentiation. These allopatric mosaic distributions suggest that speciation may have been driven by isolation during low sea‐level stands, during episodes preceding the Plio‐Pleistocene glaciations. The Makassar Strait forms a biogeographical barrier hindering eastward dispersal, corresponding to part of Wallace's Line in the terrestrial realm. Areas of maximum diversity of mangrove plants and their associated molluscs do not coincide closely. © 2013 The Natural History Museum. Biological Journal of the Linnean Society © 2013 The Linnean Society of London, 2013, 110 , 564–580.  相似文献   

7.
The origin of biodiversity in the Neotropics predominantly stems either from Gondwana breakup or late dispersal events from the Nearctic region. Here, we investigate the biogeography of a diving beetle clade whose distribution encompasses parts of the Oriental region, the Indo‐Australian archipelago (IAA) and the Neotropics. We reconstructed a dated molecular phylogeny, inferred diversification dynamics and estimated ancestral areas under different biogeographic assumptions. For the Oriental region and the IAA, we reveal repeated and complex colonization patterns out of Australia, across the major biogeographic lines in the region (e.g. Wallace's Line). The timing of colonization events across the IAA broadly coincides with the proposed timing of the formation of major geographic features in the region. Our phylogenetic hypothesis recovers Neotropical species nested in two derived clades. We recover an origin of the group in the early Eocene about 55 million yr ago, long after the break‐up of Gondwana initiated, but before a complete separation of Australia, Antarctica and the Neotropics. When allowing an old Gondwanan ancestor, we reconstruct an intricate pattern of Gondwanan vicariance and trans‐Pacific long‐distance dispersal from Australia toward the Neotropics. When restricting the ancestral range to more plausible geological area combinations in the Eocene, we infer an Australian origin with two trans‐Pacific long‐distance dispersal events toward the Neotropics. Our results support on one hand a potential Gondwanan signature associated with regional extinctions in the Cenozoic and with Antarctica serving as a link between Australia and the Neotropics. On the other hand, they also support a trans‐Pacific dispersal of these beetles toward the Andean coast in the Oligocene.  相似文献   

8.
Amongst the most significant metazoan taxa associated with gastropod molluscs is the endoparasitic copepod family Splanchnotrophidae. Currently it contains five genera with highly modified morphology and exclusively infesting nudibranch and sacoglossan sea slug hosts. The present study is a first approach towards reconstructing their phylogeny and evolution. Cladistic analysis of 109 morphological characters including 24 known splanchnotrophid species resulted in a fully resolved strict consensus tree that is discussed in morphological, functional, and geographical frameworks. Alternative topologies are also explored. Originating from paraphyletic Philoblennidae, the Splanchnotrophidae emerge as sister group to the genus Briarella. Unique synapomorphies, such as the bizarre body shapes and successive reduction of mouthparts, are discussed as adaptive traits to endoparasitism that evolved only once within copepods infesting shell‐less heterobranch gastropods. The ancestrally Indo‐Pacific Splanchnotrophidae split up into a clade of the still Indo‐Pacific genera Ceratosomicola and Arthurius, sister to a clade composed of the monophyletic amphi‐American genus Ismaila and European Splanchnotrophus emerging from paraphyletic Lomanoticola. Although initial radiation of Briarella and Splanchnotrophidae is likely to have involved chromodoridid nudibranch hosts, later phylogenies of parasites and their hosts are incongruent; intriguingly, host shifts from nudibranch to only distantly related sacoglossan species occurred at least two times independently. Such remarkable ecological plasticity is assumed to have driven splanchnotrophid diversification. Topological hypotheses and historical biogeographical and evolutionary scenarios inferred herein can be tested by future molecular research. © 2013 The Linnean Society of London  相似文献   

9.
OBJECTIVE: To describe and compare the 3' apolipoprotein (Apo) B minisatellite allele frequency distributions of Eastern Slavonic populations and their Uralic, Altaic, and Caucasian speaking neighbors. METHODS: Healthy individuals of 10 populations among Russians, Byelorussians, Komis and Bashkirs were studied for variable number tandem repeats (VNTRs) in the 3'ApoB minisatellite region. Data were analyzed with other results reported for this polymorphism in eastern Europeans and Siberians. RESULTS: Allele frequency spectra in Eastern Slavonic, Northern Caucasian and Finno-Ugric speaking populations are bimodal with the main peak in alleles 34-36 and a secondary mode around allele 48, whereas Altaic speaking populations have a unimodal allele frequency distribution with a peak of around 34-36 VNTRs. Population relationships were revealed using both multidimensional scaling analysis (based on Nei's genetic distance estimate) and testing for genetic heterogeneity. Eastern Slavonic populations (Russians, Ukrainians, Byelorussians) were most closely related to each other and formed a separate tight clusterwhen plotted. Testing for genetic heterogeneity among the Eastern Slavonic ethnic groups revealed maximum diversity among Byelorussians, followed by Russians, then Ukrainians.The 3'ApoB minisatellite variability reveals little heterogeneityamong the Eastern Slavonic ethnic groups, whereas there wassignificant heterogeneity for Northern Caucasian and Altaic speakers. CONCLUSION: For this 3'ApoB polymorphism the Eastern Slavonic populations, despite their wide geographical distribution, appear to be much more homogenous than other ethnic groups of the region. Multidimensional scaling analysis of these data allowed for differentiation between individual populations from an ethnic group even if there is little heterogeneity.  相似文献   

10.
The xanthid subfamily Chlorodiellinae is one of the most ubiquitous coral reef crab taxa in the Indo‐West Pacific region. Many species are common in coral rubble and rocky shores from Hawaii to eastern Africa, often dominating reef cryptofauna in terms of biomass. Phylogenetic analyses of mitochondrial (COX1, 12S rRNA and 16S rRNA) and nuclear (histone H3) gene sequences of 202 specimens indicate that the Chlorodiellinae is polyphyletic as presently defined. Three genera, Pilodius, Cyclodius and Chlorodiella, and two previously undescribed lineages were recovered as a well‐supported clade. In combination with morphological data, the subfamily is redefined and restricted to this clade. Two new genera, Soliella gen. n., and Luniella gen. n., are described based on features of the carapace, male thoracic sternum and male gonopods. The remaining chlorodielline genera and members of the Etisinae, a subfamily with supposedly close morphological affinities to the Chlorodiellinae, were recovered at various positions throughout the xanthid phylogeny, although with relatively low support values. These results reiterate the unresolved status of xanthid subfamilial relationships, but nevertheless provide progress for xanthid systematics.  相似文献   

11.
Although migratory pelagic fishes generally exhibit little geographic differentiation across oceans, as expected from their life history (broadcast spawning, pelagic larval life, swimming ability of adults) and the assumed homogeneity of the pelagic habitat, exceptions to the rule deserve scrutiny. One such exception is the narrow‐barred Spanish mackerel (Scomberomorus commerson Lacepède, 1800), where strong genetic heterogeneity at the regional scale has been previously reported. We investigated the genetic composition of S. commerson across the Indo‐West Pacific range using control‐region sequences (including previously published data sets), cytochrome b gene partial sequences, and eight microsatellite loci, to further explore its phylogeographic structure. All haplotypes sampled from the Indo‐Malay‐Papua archipelago (IMPA) and the south‐western Pacific coalesced into a clade (clade II) that was deeply separated (14.5% nucleotide divergence) from a clade grouping all haplotypes from the Persian Gulf and Oman Sea (clade I). Such a high level of genetic divergence suggested the occurrence of two sister species. Further phylogeographic partition was evident between the western IMPA and the regions sampled east and south of it, i.e. northern Australia, West Papua, and the Coral Sea. Strong allele‐frequency differences were found between local populations in the south‐western Pacific, both at the mitochondrial locus (Φst = 0.282–0.609) and at microsatellite loci ( = 0.202–0.313). Clade II consisted of four deeply divergent subclades (9.0–11.8% nucleotide divergence for the control region; 0.3–2.5% divergence at the cytochrome b locus). Mitochondrial subclades within clade II generally had narrow geographic distribution, demonstrating further genetic isolation. However, one particular haplogroup within clade II was present throughout the central Indo‐West Pacific: this haplogroup was found to be the sister group to a haplogroup restricted to West Papua and the Coral Sea, yielding evidence of recent secondary westward colonization. Such a complex structure is in sharp contrast with the generally weak phylogeographic patterns uncovered to date in other widely distributed, large pelagic fishes with pelagic eggs and larvae. We hypothesize that in S. commerson and possibly other Scomberomorus species, philopatric migration may play a role in maintaining the geographic isolation of populations by annihilating the potential consequences of passive dispersal. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 886–902.  相似文献   

12.
We used DNA fingerprinting with M13 phage DNA as a probe to estimate the degree of genomic variability and genetic relationships in a heterogeneous group of 13 populations from Eastern Europe and Siberia. The popultaions belong to three language families: Indo-European (Slavonic: Russians, Byelorussians), Uralic (Finno-Ugric: Maris, Mordvinians, Udmurts), and Altaic (Turkic: Bashkirs, Tatars, Chuvashes, Yakuts). Multivariate statistical analyses were used (multidimensional scaling, cluster, and multiple correspondence analyses), and coefficients of gene differentiation (Gst) were evaluated. The level of interpopulation subdivision in the various ethnic groups appeared to be different: the Byelorussian populations revealed no regional differences, in contrast to the Bashkir populations, which formed a heterogeneous group. The populations subdivided into three general clusters: Slavonic populations formed a separate tight cluster characterized by a minimal level of interpopulation diversity, Bashkir and Yakut populations formed the second cluster, and the Finno-Ugric and several populations of the Turkic linguistic groups formed the third cluster. The robustness of these results obtained by different statistical data treatments reveals that multilocus DNA fingerprinting can be reliably used for population studies.Communicated by G. P. Georgiev  相似文献   

13.
Eleotris species (Teleostei: Eleotridae) are one of the most common fish in Indo‐Pacific estuaries and insular freshwater streams. In these rivers, they are a sit‐and‐wait predator. They have an amphidromous life cycle, that is adults grow, feed and reproduce in rivers, while larvae have a marine dispersal phase. Larvae recruit back to rivers and settle in stream habitats. Primary characters used to determine Eleotris species are the presence and the disposition of cephalic sensory papillae rows on the operculum and under the eyes as well as scale row numbers. The morphology of these cephalic sensory papillae is of particular importance in this predatory genus as it is generally correlated in fish to predation and feeding. In this paper, we have established a molecular phylogeny of the genus based on the 12 mitochondrial protein‐coding genes to discuss the relationship between Indo‐Pacific Eleotris species. There is a well‐supported dichotomy in the molecular phylogeny, and this separation into two main clades is also morphologically visible, as it reveals a difference in the arrangement of cephalic sensory papillae. Indeed, the phylogeny distinguishes the species with the “open” pattern of the operculum sensory papillae and the species with the “closed” one. This phylogeny thus reflects the morphology of the opercular papillae. The evolution of this character is discussed in terms of the adaptation of the Eleotris genus to life in tropical insular river systems.  相似文献   

14.
We previously reported the occurrence of genetically‐diverse symbiotic dinoflagellates (zooxanthellae) within and between 7 giant clam species (Tridacnidae) from the Philippines based on the algal isolates' allozyme and random amplified polymorphic DNA (RAPD) patterns. We also reported that these isolates all belong to clade A of the Symbiodinium phylogeny with identical 18S rDNA sequences. Here we extend the genetic characterization of Symbiodinium isolates from giant clams and propose that they are conspecific. We used the combined DNA sequences of the internal transcribed spacer (ITS)1, 5.8S rDNA, and ITS2 regions (rDNA‐ITS region) because the ITS1 and ITS2 regions evolve faster than 18S rDNA and have been shown to be useful in distinguishing strains of other dinoflagellates. DGGE of the most variable segment of the rDNA‐ITS region, ITS1, from clonal representatives of clades A, B, and C showed minimal intragenomic variation. The rDNA‐ITS region shows similar phylogenetic relationships between Symbiodinium isolates from symbiotic bivalves and some cnidarians as does 18S rDNA, and that there are not many different clade A species or strains among cultured zooxanthellae (CZ) from giant clams. The CZ from giant clams had virtually identical sequences, with only a single nucleotide difference in the ITS2 region separating two groups of isolates. These data suggest that there is one CZ species and perhaps two CZ strains, each CZ strain containing individuals that have diverse allozyme and RAPD genotypes. The CZ isolated from giant clams from different areas in the Philippines (21 isolates, 7 clam species), the Australian Great Barrier Reef (1 isolate, 1 clam species), Palau (8 isolates, 7 clam species), and Okinawa, Japan (1 isolate, 1 clam species) shared the same rDNA‐ITS sequences. Furthermore, analysis of fresh isolates from giant clams collected from these geographical areas shows that these bivalves also host indistinguishable clade C symbionts. These data demonstrate that conspecific Symbiodinium genotypes, particularly clade A symbionts, are distributed in giant clams throughout the Indo‐Pacific.  相似文献   

15.
There has been little agreement on the phylogeny of palaeognathous birds, with major differences amongst and between results from morphological and molecular data. Two recently published phylogenies using nuclear and mitochondrial DNA have substantial agreement in overall topology, with the ostrich as sister group of all other extant palaeognaths and a kiwi‐emu‐cassowary clade. Here I report a morphological phylogeny based mainly on new characters from the tongue apparatus and cranial osteology, with a theoretical ancestor as outgroup. A new interpretation of the evolution of the avian palate is included. This phylogeny is very similar to these recent molecular results; this is the first report of such congruence, and offers a credible basis for understanding the evolution of this clade. This phylogeny is fully consistent with a Gondwana vicariance model of evolution. Dates attributed from known geological events place the first extant radiation (ostrich) in the mid‐Cretaceous, and offer a means of calibration of future molecular clock investigations. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 959–983.  相似文献   

16.
Aim Cuckoo‐shrikes and allies (Campephagidae) form a radiation of birds widely distributed in the Indo‐Pacific and Africa. Recent studies on the group have been hampered by poor taxon sampling, causing inferences about systematics and biogeography to be rather speculative. With improved taxon sampling and analyses within an explicit spatiotemporal framework, we elucidate biogeographical patterns of dispersal and diversification within this diverse clade of passerine birds. Location Africa, Asia, Australo‐Papua, the Pacific, the Philippines and Wallacea. Methods We use model‐based phylogenetic methods (Mr Bayes and garli ) to construct a phylogenetic hypothesis of the core Campephagidae (Campephagidae with the exclusion of Pericrocotus). The phylogeny is used to assess the biogeographical history of the group with a newly developed Bayesian approach to dispersal–vicariance analysis (Bayes‐diva) . We also made use of a partitioned beast analysis, with several calibration points taken from island ages, passerine mitochondrial substitution rates and secondary calibration points for passerine birds, to assess the timing of diversification and dispersal. Results We present a robust molecular phylogeny that includes all genera and 84% of the species within the core Campephagidae. Furthermore, we estimate divergence dates and ancestral area relationships. We demonstrate that Campephagidae originated in Australo‐Papua with a single lineage (Pericrocotus) dispersing to Asia early. Later, there was further extensive transoceanic dispersal from Australo‐Papua to Africa involving lineages within the core Campephagidae radiation. Main conclusions The phylogenetic relationships, along with the results of the ancestral area analysis and the timing of dispersal events, support a transoceanic dispersal scenario from Australo‐Papua to Africa by the core Campephagidae. The sister group to core Campephagidae, Pericrocotus, dispersed to mainland Asia in the late Oligocene. Asia remained uncolonized by the core Campephagidae until the Pliocene. Transoceanic dispersal is by no means an unknown phenomenon, but our results represent a convincing case of colonization over a significant water gap of thousands of kilometres from Australo‐Papua to Africa.  相似文献   

17.
Grasses exhibit a great variety of inflorescence forms and these appear homoplasious when mapped onto cladograms. The overall pattern is sufficiently complex that it is difficult to analyze inflorescence evolution. We have reduced the complexity of the problem by examining one group of grasses, the panicoid "bristle clade," which exhibits a less complex pattern of variation. The clade is morphologically defined by inflorescences bearing both spikelets and sterile bristles and is monophyletic in both morphological and molecular phylogenetic analyses. We have constructed a chloroplast DNA phylogeny of the three main genera, which finds three well-supported clades, two comprising species placed in Setaria and one of Pennisetum + Cenchrus. In this tree Cenchrus is monophyletic, but both Setaria and Pennisetum are paraphyletic. Developmental morphology of these groups is very similar at early stages. Changes in axis ramification, primordial differentiation, and axis elongation account for most variation in mature inflorescence morphology. Characters derived from comparisons of developmental sequences were optimized onto one of the most parsimonious trees. Most developmental characters were congruent with the molecular phylogeny except for three reversals in the subclade containing S. barbata, S. palmifolia, and two accessions of S. poiretiana. Changes in just a handful of developmental events account for inflorescence evolution in the bristle clade, and similar changes may account for inflorescence diversity in the grasses as a whole.  相似文献   

18.
This study produces a nearly comprehensive phylogeny for the marine gastropod group Cypraeidae (cowries) and uses this topology to examine diversification patterns in the tropics. The dataset is based on molecular sequence data from two mitochondrial genes and includes 210 evolutionary significant units (ESUs) from 170 recognized species (>80%). Systematics for the group is revised based on well‐supported clades, and tree topology is generally consistent with previously proposed classification schemes. Three new genera are introduced ( Cryptocypraea gen. nov , Palmulacypraea gen. nov , and Contradusta gen. nov ) and two previous genera are resurrected (Perisserosa and Eclogavena). One new tribe is proposed (Bistolidini). Topologies produced by a range of transition:transversion (Ti:Tv) weighting schemes in parsimony are pooled and evaluated using maximum likelihood criteria. Extensive geographical coverage shows persistent, large‐scale geographical structure in sister‐groups. Genetic divergence between subspecies is often equivalent or even greater than that between recognized species. Using ESUs as a metric, diversity throughout the Indo‐West Pacific (IWP) increases by 38%. Intra‐ and inter‐regional diversification patterns show that the IWP is the centre for speciation in cowries. The other major tropical regions of the world are inhabited by a predominantly relictual fauna; from a cowrie's eye‐view. Good dispersal ability begets larger ranges, increased extinction resistance and morphological stasis; whereas shorter larval duration results in smaller ranges, higher speciation rates, but also higher turnover. Larval duration and dispersal ability appear correlated with ocean productivity as taxa with longer‐lived larvae are associated with oligotrophic conditions; whereas taxa with shorter larval durations are associated with eutrophic, continental conditions. This tendency is carried to the extreme in temperate or upwelling regions where a planktonic phase is completely lost and crawl‐away larvae evolve multiple times. A strong phylogenetic trend supports these observations as lineages leading up to and including the derived Indo‐West Pacific Erroneinae clade contain taxa predominantly restricted to continental habitats and have undergone the greatest evolutionary radiations in their respective regions. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 79, 401– 459.  相似文献   

19.
The therevoid clade represents a group of four families (Apsilocephalidae, Evocoidae, Scenopinidae and Therevidae) of lower brachyceran Diptera in the superfamily Asiloidea. The largest of these families is that of the stiletto flies (Therevidae). A large‐scale (i.e. supermatrix) phylogeny of Therevidae is presented based on DNA sequence data from seven genetic loci (16S, 18S and 28S ribosomal DNA and four protein‐encoding genes: elongation factor 1‐alpha, triose phosphate isomerase, short‐wavelength rhodopsin and the CPSase region of carbamoyl‐phosphate synthase‐aspartate transcarbamoylase‐dihydroorotase). Results are presented from Bayesian phylogenetic analyses of approximately 8.7 kb of sequence data for 204 taxa representing all subfamilies and genus groups of Therevidae. Our results strongly support the sister‐group relationship between Therevidae and Scenopinidae, with Apsilocephalidae as sister to Evocoidae. Previous estimates of stiletto fly phylogeny based on morphology or DNA sequence data, or supertree analysis, have failed to find significant support for relationships among subfamilies. We report for the first time strong support for the placement of the subfamily Phycinae as sister to the remaining Therevidae, originating during the Mid Cretaceous. As in previous studies, the sister‐group relationship between the species‐rich subfamilies Agapophytinae and Therevinae is strongly supported. Agapophytinae are recovered as monophyletic, inclusive of the Taenogera group. Therevinae comprise the bulk of the species richness in the family and appear to be a relatively recent and rapid radiation originating in the southern hemisphere (Australia + Antarctica + South America) during the Late Cretaceous. Genus groups are defined for all subfamilies based on these results.  相似文献   

20.
Until recently, Histoplasma capsulatum was believed to harbour three varieties, var. capsulatum (chiefly a New World human pathogen), var. duboisii (an African human pathogen) and var. farciminosum (an Old World horse pathogen), which varied in clinical manifestations and geographical distribution. We analysed the phylogenetic relationships of 137 individuals representing the three varieties from six continents using DNA sequence variation in four independent protein‐coding genes. At least eight clades were idengified: (i) North American class 1 clade; (ii) North American class 2 clade; (iii) Latin American group A clade; (iv) Latin American group B clade; (v) Australian clade; (vi) Netherlands (Indonesian?) clade; (vii) Eurasian clade and (viii) African clade. Seven of eight clades represented genetically isolated groups that may be recognized as phylogenetic species. The sole exception was the Eurasian clade which originated from within the Latin American group A clade. The phylogenetic relationships among the clades made a star phylogeny. Histoplasma capsulatum var. capsulatum individuals were found in all eight clades. The African clade included all of the H. capsulatum var. duboisii individuals as well as individuals of the other two varieties. The 13 individuals of var. farciminosum were distributed among three phylogenetic species. These findings suggest that the three varieties of Histoplasma are phylogenetically meaningless. Instead we have to recognize the existence of genetically distinct geographical populations or phylogenetic species. Combining DNA substitution rates of protein‐coding genes with the phylogeny suggests that the radiation of Histoplasma started between 3 and 13 million years ago in Latin America.  相似文献   

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