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1.
Using characters from mitochondrial DNA to construct maximum parsimony and maximum likelihood trees, we performed a phylogenetic analysis on representative species of 14 genera: 12 that belong to the treefrog family Rhacophoridae and two, Amolops and Rana, that are not rhacophorids. Our results support a phylogenetic hypothesis that depicts a monophyletic family Rhacophoridae. In this family, the Malagasy genera Aglyptodactylus, Boophis, Mantella, and Mantidactylus form a well-supported sister clade to all other rhacophorid genera, and Mantella is the sister taxon to Mantidactylus. Within the Asian/African genera, the genus Buergeria forms a well-supported clade of four species. The genera, except for Chirixalus, are generally monophyletic. An exception to this is that Polypedates dennysii clusters with species of Rhacophorus, suggesting that the taxonomy of the rhacophorids should be revised to reflect this relationship. Chirixalus is not monophyletic. Unexpectedly, there is strong support for Chirixalus doriae from Southeast Asia forming a clade with species of the African genus Chiromantis, suggesting that Chiromantis dispersed to Africa from Asia. Also, there is strong support for the sister taxon relationship of Chirixalus eiffingeri and Chirixalus idiootocus apart from other congeners.  相似文献   

2.
We tested the previous hypotheses of the phylogenetic position and monophyly of the caddisfly family Polycentropodidae. We also tested previous hypotheses about the internal generic relationship within the family by including 15 ingroup genera, many of them also represented by the genotype. All families that were previously taxonomically associated with the polycentropodids were included in the analysis. The total data set of 2225bp representing sequences of combined nuclear and mitochondrial genes and 171 taxa, was analyzed using Bayesian inference. We found strong support for a monophyletic Polycentropodidae with Ecnomidae as the closest sister group. The recently erected families Kambaitipsychidae and Pseudoneureclipsidae were monophyletic and distantly related to the Polycentropodidae. Within Polycentropodidae, monophyly and validity of the genera Neucentropus, Neureclipsis, Cyrnus, Holocentropus, Tasmanoplegas, Pahamunaya, Cernotina and Cyrnellus was strongly supported, while the genera Polycentropus, Polyplectropus, Plectrocnemia, Placocentropus and Nyctiophylax were all polyphyletic. The New Caledonian species were polyphyletic and represented three distinct clades. The sister group to the New Caledonian clades are from Australia, New Zealand and Chile, respectively. The Vanuatu species evolved after dispersal from the Fiji Islands. New internal primers for cytochrome oxidase I sequences of Trichoptera are introduced.  相似文献   

3.
Members of the family Conopidae (Diptera) have been the focus of little targeted phylogenetic research. The most comprehensive test of phylogenetic support for the present subfamily classification of Conopidae is presented here using 66 specimens, including 59 species of Conopidae and seven outgroup taxa. Relationships among subfamily clades are also explored. A total of 6824 bp of DNA sequence data from five gene regions (12S ribosomal DNA, cytochrome c oxidase subunit I, cytochrome b, 28S ribosomal DNA and alanyl‐tRNA synthetase) are combined with 111 morphological characters in a combined analysis using both parsimony and Bayesian methods. Parsimony analysis recovers three shortest trees. Bayesian analysis recovers a nearly identical tree. Five monophyletic subfamilies of Conopidae are recovered. The rarely acknowledged Zodioninae is restored, including the genera Zodion and Parazodion. The genus Sicus is removed from Myopinae. Morphological synapomorphies are discussed for each subfamily and inter‐subfamily clade, including a comprehensive review of the character interpretaions of previous authors. Included are detailed comparative illustrations of male and female genitalia of representatives of all five subfamilies with new morphological interpretation.  相似文献   

4.
The gene encoding 18S small subunit ribosomal RNA (ssu rRNA) was sequenced in the sessiline peritrichs Opisthonecta minima and Opisthonecta matiensis, whose free-swimming, paedomorphic trophonts resemble telotrochs. Using these new sequences, phylogenetic trees were constructed with four different methods to test a previously published association between Opisthonecta henneguyi and members of the families Vorticellidae and Astylozoidae. All trees had similar topologies, with O. minima, O. henneguyi, Vorticella microstoma, and Astylozoon enriquesi forming a well-supported, certainly monophyletic clade. On the basis of genetic evidence, genera of the families Opisthonectidae and Astylozoidae are assigned to the family Vorticellidae, which already includes some species with free-swimming morphotypes. The ssu rRNA sequence of O. matiensis places it in the family Epistylididae; its taxonomic revision will be left to another group of authors. A close association of Ophrydium versatile with members of the family Vorticellidae was confirmed, casting doubt on the validity of the family Ophrydiidae. Epistylis galea, Campanella umbellaria, and Opercularia microdiscum are confirmed as comprising an extremely distinct, monophyletic, but morphologically heterogeneous clade that is basal to other clades of sessiline peritrichs.  相似文献   

5.
The Caribbean Island Biodiversity Hotspot is composed primarily of the Bahamas and Greater and Lesser Antilles. A total of 180 genera (727 spp., ca. 9% of the species endemic to the Antilles) are restricted to this hotspot. Most of these genera are unispecific (51%), a pattern that is also found on other islands of the world. The majority of the endemic genera belong to the “Core Eudicot” clade, and they were published in two time periods (1854–1878 and 1904–1928). There are molecular phylogenies available for 63 of the endemic genera. However, phylogenetic reconstructions of only 21 genera are based on more than one independent DNA region and have well-supported clades and good taxonomic sampling. Six of the endemic genera form part of early-branching groups. We could not infer biogeographical conclusions from the molecular phylogenies of most of the endemic genera (43: 68%). There is an urgent need for (1) additional field studies to learn the conservation status of these genera, (2) effective protection of the habitats where the most endangered genera occur, and (3) additional biological and systematic studies of the least understood genera.  相似文献   

6.
The Lejeuneaceae are the largest family of the liverworts (Hepaticae), with almost a thousand species in 91 currently accepted genera. We analysed phylogenetic relationships of 69 genera, representing all major subfamilies and tribes recognized in the family, by using 49 informative morphological characters (31 gametophytic, 18 sporophytic), one chemical character, and applying equal and successive weighting of characters and parsimony analysis. In all trees recovered, the Lejeuneaceae were monophyletic with Nipponolejeunea (subfam. Nipponolejeuneoideae) forming the basalmost lineage. The remaining genera clustered in two major groups, the monophyletic Lejeuneoideae (52 genera) and the paraphyletic Ptychanthoideae (16 genera). Within each, several multigeneric lineages corresponding in part to previously described taxa were recovered: the Acrolejeuneinae and Ptychanthinae clades in the Ptychanthoideae, and the Brachiolejeuneinae, Lejeuneeae and Tuyamaella–Cololejeunea clades in the Lejeuneoideae. Bryopteris , a genus sometimes treated as a separate family, was nested in the Ptychanthinae clade. The Tuyamaella–Cololejeunea lineage corresponded with three previously recognized subfamilies (Cololejeuneoideae, Myriocoleoideae and Tuyamaelloideae) and contained genera with neotenic features, in two subclades. These features seemed to have originated by multiple heterochronic events: single origins were detected for 'protonemal neoteny' and 'primary neoteny', whereas 'secondary neoteny' probably evolved twice. Relationships within the large Lejeuneeae clade (43 genera) remained largely unresolved, although several putative lineages were detected in majority rule trees. Additional characters such as DNA sequences may provide better phylogenetic resolution in this group.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 391–410.  相似文献   

7.
The gene coding for the small subunit ribosomal RNA molecule was sequenced in three marine spirotrichs: Pseudoamphisiella lacazei, P. alveolata, and Parabirojimia similis, the systematic positions of which remain unclear in spite of recent progress. Phylogenetic trees were constructed by means of neighbor-joining (NJ), least-squares (LS), maximum parsimony (MP), and Bayesian inference (BI) methods in order to test previously inferred phylogenetic assignments of Pseudoamphisiella and Parabirojimia based on morphological and morphogenetic data. The main results are that: (1) all trees constructed have similar topologies in which the genus Parabirojimia derives at the base of the class Stichotrichia, which suggests that it might represent a unique taxon at about suborder or even-order level near urostylids; (2) the present study supports the conclusion reported by previous researchers that urostylids could be a paraphyletic assemblage and that Uroleptus and Paruroleptus should be removed from the order Urostylida; (3) Pseudoamphisiellidae/Pseudoamphisiella always clusters with Prodiscocephalus borrori rather than with urostylids, which indicates that they might represent an ancestral form for both discocephaline and urostylid species; (4) the monophyly of the traditional suborder Discocephalina and typical euplotids is consistently rejected. Based on both morphological/morphogenetical and molecular data obtained, a new suborder Parabirojimina n. subord. is suggested, which currently includes one family, Parabirojimidae n. fam., and the single genus Parabirojimia.  相似文献   

8.
Trichodesmium spp. play key roles in global carbon and nitrogen budgets and thus defining what controls their productivity is important for understanding climate change. While iron availability has been shown to be an important chemical factor for controlling both growth and nitrogen fixation rates in Trichodesmium , all culture experiments to date have focused solely on representatives from one clade of Trichodesmium . Genomic sequence analysis determined that the Trichodesmium erythraeum (IMS101) genome contains many of the archetypical genes involved in the prokaryotic iron stress response. Focusing on three of these genes, isiB , idiA and feoB , we found that all three showed an iron stress response in axenic T. erythraeum (IMS101), and their sequences were well conserved across four species in our Trichodesmium culture collection [consisting of two T. erythraeum strains (IMS101 and GBRTRLI101), two Trichodesmium tenue strains (Z-1 and H9-4), Trichodesmium thiebautii and Trichodesmium spiralis ]. With clade-specific quantitative PCR (qPCR) primers for one of these genes, isiB , we found that high isiB expression at low Fe levels corresponded to specific reductions in N2 fixation rates in both major phylogenetic clades of Trichodesmium (the T. erythraeum clade and T. tenue clade). With regard to the two clades, the most significant difference determined was temperature optima, while more subtle differences in growth, N2 fixation rate and gene expression responses to Fe stress were also observed. However the apparent conservation of the Fe stress response in the Trichodesmium genus suggests that it is an important adaptation for their niche in the oligotrophic ocean.  相似文献   

9.
 A data matrix of 143 morphological and chemical characters for 142 genera of euasterids according to the APG system was compiled and complemented with rbcL and ndhF sequences for most of the genera. The data were subjected to parsimony analysis and support was assessed by bootstrapping. Strict consensus trees from analyses of morphology alone and morphology + rbcL + ndhF are presented. The morphological data recover several groups supported by molecular data but at the level of orders and above relationships are only superficially in agreement with molecular studies. The analyses provide support for monophyly of Gentianales, Aquifoliales, Apiales, Asterales, and Dipsacales. All data indicate that Adoxaceae are closely related to Dipsacales and hence they should be included in that order. The trees were used to assess some possible morphological synapomorphies for euasterids I and II and for the orders of the APG system. Euasterids I are generally characterised by opposite leaves, entire leaf margins, hypogynous flowers, “early sympetaly” with a ring-shaped corolla primordium, fusion of stamen filaments with the corolla tube, and capsular fruits. Euasterids II often have alternate leaves, serrate-dentate leaf margins, epigynous flowers, “late sympetaly” with distinct petal primordia, free stamen filaments, and indehiscent fruits. It is unclear which of these characters represent synapomorphies and symplesiomorphies for the two groups, respectively, and there are numerous expections to be interpreted as reversals and parallelisms. Received August 28, 2000 Accepted August 7, 2001  相似文献   

10.
A collection of 247 true morels (Morchella spp.) primarily from the Mediterranean and Aegean Regions of Southern Turkey, were analyzed for species diversity using partial RNA polymerase I (RPB1) and nuclear ribosomal large subunit (LSU) rDNA gene sequences. Based on the result of this initial screen, 62 collections representing the full range of genetic diversity sampled were subjected to multigene phylogenetic species recognition based on genealogical concordance (GCPSR). The 62-taxon dataset consisted of partial sequences from three nuclear protein-coding genes, RNA polymerase I (RPB1), RNA polymerase II (RPB2), translation elongation factor (EF1-α), and partial LSU rDNA gene sequences. Phylogenetic analyses of the individual and combined datasets, using maximum parsimony (MP) and maximum likelihood (ML), yielded nearly fully resolved phylogenies that were highly concordant topologically. GCPSR analysis of the 62-taxon dataset resolved 15 putative phylogenetically distinct species. The early diverging Elata (black morels) and Esculenta Clades (yellow morels) were represented, respectively, by 13 and two species. Because a Latin binomial can be applied with confidence to only one of the 15 species (Morchella semilibera), species were identified by clade (Mel for Elata and Mes for Esculenta) followed by a unique Arabic number for each species within these two clades. Eight of the species within the Elata Clade appear to be novel, including all seven species within the Mel-20-to-31 subclade and its sister designated Mel-25. Results of the present study provide essential data for ensuring the sustainability of morel harvests through the formulation of sound conservation policies.  相似文献   

11.
Sciomyzidae is a family of acalyptrate flies with 546 species in 61 genera that is among the most extensively studied groups of higher Diptera. Most of the known larvae are obligate enemies of Gastropoda. Hundreds of studies published over the past 50 years have resulted in detailed information concerning morphology of adults and immature stages, biology, development, behaviour, phenology and distribution. However, studies of phylogenetic relationships are based almost exclusively on morphological characters of adults, and no comprehensive molecular analysis across the family has been published. Here we fill this void by generating and analysing molecular data for 54 species of Sciomyzidae (22 genera), including Phaeomyiidae (one genus), and seven representative species of five other families of Sciomyzoidea (Coelopidae, Dryomyzidae, Helcomyzidae, Heteromyzidae and Huttoninidae) as outgroups. The reconstruction is based on morphological characters as well as nucleotide sequences for genes from the mitochondrial (12S, 16S, COI, COII, Cytb) and nuclear genome (28S, EF1α). The results are compared with recent morphological analyses. Our analyses support the monophyly of Sciomyzidae + Phaeomyiidae, and place Phaeomyiinae as a unique lineage within Sciomyzidae. A modified classification comprising three subfamilies is proposed. The major subfamily, Sciomyzinae, consists of two monophyletic and well separated groups, the tribes Sciomyzini and Tetanocerini.  相似文献   

12.
Here, we present a comprehensive phylogenetic analysis based on nuclear and mitochondrial DNA sequences of rodents of the subfamily Sigmodontinae. The emphasis is placed on the large tribe Phyllotini; sampling includes for the first time in any molecular‐based phylogenetic analysis representatives of several genera traditionally considered to be phyllotines. Given the broad taxonomic sampling, results provide substantial improvements in our knowledge on both the structure of the sigmodontine radiation and of phyllotine phylogenetic relationships. For instance, the tribe Ichthyomyini was not recovered monophyletic. Similarly, in a novel hypothesis on the contents of the tribe Phyllotini, it is shown that unlike Galenomys, the genera Chinchillula, Neotomys and Punomys are not phyllotines. The later genera together with Andinomys, Euneomys, Irenomys and Juliomys form part of novel generic clades of mostly Andean sigmodontine rodents. More in general, results strongly suggest the occurrence of several instances of putative morphological convergence among distinct sigmodontine lineages (e.g. among now considered to be ichthyomyines; between Phyllotini and some Andean taxa; among EuneomysNeotomys and Reithrodon). Finally, we suggest that the historical biogeography of the sigmodontine rodents is far more complex than earlier envisioned.  相似文献   

13.
We present a framework for biodiversity metrics that organizes the growing panoply of metrics. Our framework distinguishes metrics based on the type of information–abundance, phylogeny, function–and two common properties–magnitude and variability. Our new metrics of phylogenetic diversity are based on a partition of the total branch lengths of a cladogram into the proportional share of each species, including: a measure of divergence which standardizes the amount of evolutionary divergence by species richness and time depth of the cladogram; a measure of regularity which is maximal when the tree is perfectly symmetrical so that all species have the same proportional branch lengths; a measure that combines information on the magnitude and variability of abundance with phylogenetic variability, and a measure of phylogenetically weighted effective mean abundance; and indicate how those metrics can be decomposed into α and β components. We illustrate the utility of these new metrics using empirical data on the bat fauna of Manu, Peru. Divergence was greatest in lowland rainforest and at the transition between cloud and elfin forests, and least in upper elfin forests and in cloud forests. In contrast, regularity was greatest in lowland rainforest, dipping to its smallest values in mid‐elevation cloud forests, and then increasing in high elevation elfin forests. These patterns indicate that the first species to drop out with increasing elevation are ones that are closely related to other species in the metacommunity. Measures of the effective number of phylogenetically independent or distinct species decreased very rapidly with elevation, and β‐diversity was larger. In contrast, a comparison of feeding guilds shows a different effect of phylogenetic patterning. Along the elevational gradient, each guild generally loses some species from each clade–rather than entire clades–explaining the maintenance of functional diversity as phylogenetic diversity decreases.  相似文献   

14.
15.
The status of the genera Euparagonimus Chen, 1963 and Pagumogonimus Chen, 1963 relative to Paragonimus Braun, 1899 was investigated using DNA sequences from the mitochondrial cytochrome c oxidase subunit I (CO1) gene (partial) and the nuclear ribosomal DNA second internal transcribed spacer (ITS2). In the phylogenetic trees constructed, the genus Pagumogonimus is clearly not monophyletic and therefore not a natural taxon. Indeed, the type species of Pagumogonimus, P. skrjabini from China, is very closely related to Paragonimus miyazakii from Japan. The status of Euparagonimus is less obvious. Euparagonimus cenocopiosus lies distant from other lungflukes included in the analysis. It can be placed as sister to Paragonimus in some analyses and falls within the genus in others. A recently published morphological study placed E. cenocopiosus within the genus Paragonimus and probably this is where it should remain.  相似文献   

16.
Despite much research on the socially parasitic large blue butterflies (genus Maculinea) in the past 40 years, their relationship to their closest relatives, Phengaris, is controversial and the relationships among the remaining genera in the Glaucopsyche section are largely unresolved. The evolutionary history of this butterfly section is particularly important to understand the evolution of life history diversity connected to food-plant and host-ant associations in the larval stage. In the present study, we use a combination of four nuclear and two mitochondrial genes to reconstruct the phylogeny of the Glaucopsyche section, and in particular, to study the relationships among and within the Phengaris-Maculinea species. We find a clear pattern between the clades recovered in the Glaucopsyche section phylogeny and their food-plant associations, with only the Phengaris-Maculinea clade utilising more than one plant family. Maculinea is, for the first time, recovered with strong support as a monophyletic group nested within Phengaris, with the closest relative being the rare genus Caerulea. The genus Glaucopsyche is polyphyletic, including the genera Sinia and Iolana. Interestingly, we find evidence for additional potential cryptic species within the highly endangered Maculinea, which has long been suspected from morphological, ecological and molecular studies.  相似文献   

17.
We examine phylogenetic relationships among salamanders of the family Salamandridae using approximately 2700 bases of new mtDNA sequence data (the tRNALeu, ND1, tRNAIle, tRNAGln, tRNAMet, ND2, tRNATrp, tRNAAla, tRNAAsn, tRNACys, tRNATyr, and COI genes and the origin for light-strand replication) collected from 96 individuals representing 61 of the 66 recognized salamandrid species and outgroups. Phylogenetic analyses using maximum parsimony and Bayesian analysis are performed on the new data alone and combined with previously reported sequences from other parts of the mitochondrial genome. The basal phylogenetic split is a polytomy of lineages ancestral to (1) the Italian newt Salamandrina terdigitata, (2) a strongly supported clade comprising the "true" salamanders (genera Chioglossa, Mertensiella, Lyciasalamandra, and Salamandra), and (3) a strongly supported clade comprising all newts except S. terdigitata. Strongly supported clades within the true salamanders include monophyly of each genus and grouping Chioglossa and Mertensiella as the sister taxon to a clade comprising Lyciasalamandra and Salamandra. Among newts, genera Echinotriton, Pleurodeles, and Tylototriton form a strongly supported clade whose sister taxon comprises the genera Calotriton, Cynops, Euproctus, Neurergus, Notophthalmus, Pachytriton, Paramesotriton, Taricha, and Triturus. Our results strongly support monophyly of all polytypic newt genera except Paramesotriton and Triturus, which appear paraphyletic, and Calotriton, for which only one of the two species is sampled. Other well-supported clades within newts include (1) Asian genera Cynops, Pachytriton, and Paramesotriton, (2) North American genera Notophthalmus and Taricha, (3) the Triturus vulgaris species group, and (4) the Triturus cristatus species group; some additional groupings appear strong in Bayesian but not parsimony analyses. Rates of lineage accumulation through time are evaluated using this nearly comprehensive sampling of salamandrid species-level lineages. Rate of lineage accumulation appears constant throughout salamandrid evolutionary history with no obvious fluctuations associated with origins of morphological or ecological novelties.  相似文献   

18.
This study presents a general cladistic analysis of pisaurid genera, with emphasis on the Neotropical genera Architis Simon and Staberius Simon. The analysis was based on a matrix with 21 terminal taxa: eight species of Architis , Staberius spinipes (Taczanowski), seven exemplars of other pisaurid genera and five outgroup taxa. These terminals were scored for 59 morphological and three behavioural characters. An analysis with all characters equally weighted resulted in two most parsimonious trees, differing only in the position of Architis colombo Santos. In both trees Pisauridae arouse as a monophyletic group, and the exemplars of Architis composed a clade with S. spinipes . Contrary to hypotheses from the literature, Thalassius Simon emerged as sister-group of all remaining pisaurids, not as a close relative of Dolomedes Latreille. The genera Tinus F.O.P. -Cambridge and Thaumasia Perty appeared in the trees as the closest relatives of Architis and Staberius Simon. The analysis strongly supported S. spinipes as the sister-group of A. helveola (Simon), indicating that Architis as currently delimited is paraphyletic. Based on these results, Staberius is considered a subjective junior synonym of Architis . Additionally, the genus Mimicosa Petrunkevitch, originally described in Tetragnathidae, is transferred to Pisauridae and considered a junior synonym of Architis . Two species are proposed as junior synonyms of A. spinipes comb.n. Mimicosa spinosa Petrunkevitch and Staberius lemoulti Caporiacco.  相似文献   

19.
A few genera of angiosperms are known as 'resurrection plants' since their leaves withstand complete desiccation. In many organisms, including some resurrection plants, desiccation tolerance is associated with the accumulation of special carbohydrates. We examined whether this is also true for the two European angiosperm genera of resurrection plants, Ramonda and Haberlea in the Gesneriaceae. Using gas chromatography, non-structural carbohydrates were determined as a percentage of the dry weight in leaves of Ramonda nathaliae subjected to various desiccation regimes. Sucrose was the predominant soluble carbohydrate in all samples, and its level steadily increased from 2 to 10% during desiccation. Starch amounted to ca 2% in control leaves and disappeared completely within 8 days of desiccation. Considerable amounts (1–2.5%) of raffinose and smaller amounts of its precursor galactinol (1-a-galactosyl- myo -inositol) were present in control leaves; these carbohydrates showed only minor changes upon desiccation. Similar results were obtained when excised leaves of Ramonda nathaliae, Ramonda myconi and Haberlea rhodopensis were subjected to desiccation. These data indicate that sucrose accumulation is connected to desiccation tolerance in Gesneriaceae; the presence of raffinose may be a pre-adaptation since this sugar prevents crystallization of sucrose during drying.  相似文献   

20.
Phylogenetic relationships and species boundaries of Australian burrowing freshwater crayfish belonging to the genera Engaeus, Engaewa, Geocharax, Gramastacus and Tenuibranchiurus are investigated using combined mitochondrial and nuclear DNA sequence data and Bayesian and Maximum Parsimony methods. Phylogenies are statistically compared to previously published hypotheses. Engaeus, Engaewa, Geocharax, Gramastacus and Tenuibranchiurus form a strongly supported monophyletic clade. This grouping is independently supported by morphology but unites geographically highly disjunct lineages. Our data show two cryptic species in Geocharax, one cryptic species in Gramastacus and two cryptic species within the highly divergent Engaeus lyelli lineage. Using a Bayesian relaxed molecular clock method, the 16S rDNA data show generic-level diversification coinciding with the transition from a wet to arid palaeoclimate near the mid Miocene.  相似文献   

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