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1.
Compared to their calcified sister group, order Cheilostomata, uncalcified ctenostome bryozoans exhibit relatively simple and often inconsistent morphologies, making them particularly suitable candidates for the use of molecular tools to delimit species and examine their interrelationships. The family Vesiculariidae is composed of six genera, three of which, Zoobotryon, Avenella and Watersiana are monotypic, and one, Vesicularia, encompasses four species. The majority of vesiculariid diversity, however, is found in Amathia (39 species) and Bowerbankia (21 species). The respective monophyletic status for Amathia and Bowerbankia has recently been put into question by molecular evidence and is being further examined in this study. Multigene (ssrDNA, rrnL, cox1) phylogenetic analysis revealed that Bowerbankia is paraphyletic to the inclusion of Zoobotryon and Amathia, where the latter was resolved as non‐monophyletic. Although Vesicularia also nested within this paraphyletic assemblage in some of the analyses, Bayesian topology testing did not support this result. Our results are discussed within the context of published morphological evidence and lead to the conclusion that Bowerbankia and Zoobotryon should be classified as junior subjective synonyms of Amathia. A revised nomenclature is provided. Furthermore, we examined genetic divergences between widely distributed supposed conspecific species and discovered possible cryptic diversity in the outgroup taxon Anguinella palmata and in Bowerbankia citrina, Amathia vidovici and Amathia crispa.  相似文献   

2.
A phylogenetic analysis of the extant Aeshnidae (Odonata: Anisoptera)   总被引:1,自引:1,他引:0  
Abstract A cladistic analysis of the world Aeshnidae is presented, based on fifty-eight characters of adult and larval anatomy. The ingroup taxa include all the extant genera of Aeshnidae, and the austropetaliid genera Phyllopetalia and Hypopetalia were chosen as the outgroup. The strict consensus tree obtained after successive weighting shows that the subgroups defined traditionally for Aeshnidae are paraphyletic or polyphyletic. The previous reclassification derived from analyses based on wing venation is supported in terms of the monophyly of Aeshnidae, Gomphaeschninae and its sister group comprising the remaining Aeshnidae. Gomphaeschninae is confirmed as sister group of the remaining Aeshnidae (= Aeshnodea Bechly). The sister-group relationships between Gomphaeschna + Sarasaeschna and Linaeschna + Oligoaeschna are corroborated. Within Aeshnodea, three monophyletic groups emerged: Boyeria + ( Petaliaeschna + ( Limnetron + Gynacanthaeschna + Periaeschna )) + (( Cephalaeschna + Caliaeschna ) + ( Allopetalia ( Notoaeschna + Spinaeschna ))); Dendroaeschna + ( Epiaeschna + ( Aeschnophlebia + ( Nasiaeschna + ( Tetracanthagyna + Brachytron )))); and Polycanthagyna + ( Basiaeschna + ( Amphiaeschna + ( Indaeschna + ( Oplonaeschna + ( Racenaeschna + Plattycantha + Agyrtacantha + Triacanthagyna + ( Subaeschna + Austrogynacantha + Gynacantha ) + ( Heliaeschna + ( Neuraeschna + Staurophlebia ))) + (( Castoraeschna + Coryphaeschna + Remartinia ) + ( Oreaeschna + ( Aeshna + ( Anaciaeschna + ((' A .' isosceles + Andaeshna ) + ( Anax + Hemianax )))))). Additional informative characters are required to test the relationships suggested here between the main groups of Aeshnodea and some enigmatic basal taxa ( Antipodophlebia , Austroaeschna , Acanthaeschna , Telephlebia , Austrophlebia and Planaeschna ).  相似文献   

3.
The Afrotropical fruit fly genus Ceratitis MacLeay is an economically important group that comprises over 89 species, subdivided into six subgenera. Cladistic analyses of morphological and host use characters have produced several phylogenetic hypotheses for the genus. Only monophyly of the subgenera Pardalaspis and Ceratitis (sensu stricto) and polyphyly of the subgenus Ceratalaspis are common to all of these phylogenies. In this study, the hypotheses developed from morphological and host use characters are tested using gene trees produced from DNA sequence data of two mitochondrial genes (cytochrome oxidase I and NADH-dehydrogenase subunit 6) and a nuclear gene (period). Comparison of gene trees indicates the following relationships: the subgenus Pardalaspis is monophyletic, subsection A of the subgenus Pterandrus is monophyletic, the subgenus Pterandrus may be either paraphyletic or polyphyletic, the subgenus Ceratalaspis is polyphyletic, and the subgenus Ceratitis s. s. might not be monophyletic. In addition, the genera Ceratitis and Trirhithrum do not form reciprocally monophyletic clades in the gene trees. Although the data statistically reject monophyly for Trirhithrum under the Shimodaira-Hasegawa test, they do not reject monophyly of Ceratitis.  相似文献   

4.
A recent phylogenetic study based on morphological, biochemical and early life history characters resurrected the genus Scartomyzon (jumprock suckers, c . eight−10 species) from Moxostoma (redhorse suckers, c . 10–11 species) and advanced the understanding of relationships among species in these two genera, and the genealogical affinities of these genera with other evolutionary lineages within the tribe Moxostomatini in the subfamily Catostominae. To further examine phylogenetic relationships among moxostomatin suckers, the complete mitochondrial (mt) cytochrome b gene was sequenced from all species within this tribe and representative outgroup taxa from the Catostomini and other catostomid subfamilies. Phylogenetic analysis of gene sequences yielded two monophyletic clades within Catostominae: Catostomus + Deltistes + Xyrauchen + Erimyzon + Minytrema and Moxostoma + Scartomyzon + Hypentelium + Thoburnia . Within the Moxostomatini, Thoburnia was either unresolved or polyphyletic; Thoburnia atripinnis was sister to a monophyletic Hypentelium . In turn, this clade was sister to a monophyletic clade containing Scartomyzon and Moxostoma . Scartomyzon was never resolved as monophyletic, but was always recovered as a polyphyletic group embedded within Moxostoma , rendering the latter genus paraphyletic if ' Scartomyzon ' continues to be recognized. Relationships among lineages within the Moxostoma and' Scartomyzon 'clade were resolved as a polytomy. To better reflect phylogenetic relationships resolved in this analysis, the following changes to the classification of the tribe Moxostomatini are proposed: subsumption of' Scartomyzon 'into Moxostoma ; restriction of the tribe Moxostomatini to Moxostoma ; resurrect the tribe Erimyzonini, containing Erimyzon and Minytrema , classified as incertae sedis within Catostominae; retain the tribe Thoburniini.  相似文献   

5.
A maximum parsimony phylogeny of 14 Caucasian species of rock lizards, genus Ijicerta , subgenus Archaeolacerta , was constructed from mitochondrial cytochrome b and ATPase 6 partial gene sequences. Congruence analyses were carried out between the two genes. A synthesis of the data sets reveals three well supported monophyletic groups: (1) the caucasica group including ( Lacerta derjugini (( Lalpina, L. clarkorum ) ( L. caucasica, L. daghestanica ))); (2) the rudis group including ( L. parvula ( L. portschinskii ( L. vakntini, L. rudis ))); and (3) the saxicola group including ( L. mixta ( L. nairensis ( L. saxicola, L. raddeijj ). Despite the diagnosis of three groups, the placement of L. praticola as a basal taxon is uncertain, as are the relationships among the three groups. The mitochondrial DNA sequence data suggested prior hybridization between L. mixta and L. alpina and possibly between L. saxicola and L. nairensis. Lacerta raddei was resolved as a paraphyletic species on the mtDNA tree; this may result from either hybridization or random gene sorting.  相似文献   

6.
Thelypteridaceae is one of the largest families of polypodioid ferns. The generic classification of the family is still controversial because of high levels of convergent or parallel evolution of morphological characters and a lack of molecular phylogenetic studies. In the present study, phylogenetic analyses of three chloroplast regions (rbcL, rps4 and trnL-trnF intergenic spacer region) for 115 taxa, representing 27 recognized segregates in the family, were conducted to explore infrafamilial relationships and gain further understanding of generic boundaries. The phylogenetic reconstructions resolved six distinct clades (Clade I-VI) with strong support. Seven genera: Cyclogramma, Macrothelypteris, Oreopteris, Phegopteris, Pseudophegopteris, Stegnogramma, and Thelypteris are recognized from Clades I, II, IV, and V. In Clade III, Metathelypteris was supported as monophyletic, but the other segregates Amauropelta, Coryphopteris, and Parathelypteris were polyphyletic or paraphyletic, preventing clear recognition of generic boundaries within this clade without additional sampling. Considering great morphological homoplasy within Clade VI, a large genus Cyclosorus is recognized to comprise several small recognized segregates. Within this clade, Pronephrium, and Christella were revealed to be polyphyletic, but several Asian-endemic segregates, such as Glaphyropteridopsis, Mesopteris, and Pseudocyclosorus were strongly supported as monophyletic. Analyses of the evolution of morphological character states on the molecular phylogeny showed extremely high levels of homoplastic evolution for many diagnostic characters.  相似文献   

7.
Nuclear ribosomal DNA (internal transcribed spacer region) and chloroplast DNA (trnL-trnF region) were sequenced from 40 samples representing all three genera (Brachelyma, Dichelyma, and Fontinalis) and 18 species of the aquatic moss family, Fontinalaceae. Phylogenetic reconstructions recovered from separate and combined analyses were used to test the hypotheses that Fontinalis and Dichelyma are monophyletic (Brachelyma is monotypic), that groups of species within Fontinalis based on leaf morphology (keeled, concave, plane) form monophyletic groups, and that species delineation based on morphological characters within Fontinalis are congruent with nr- and cpDNA gene trees. Using Brachelyma subulata to root the tree, both Dichelyma and Fontinalis are monophyletic and patristically divergent (each united by >15 synapomorphic mutations). Groups of species within Fontinalis defined by leaf morphology are polyphyletic and it is clear that leaf morphology is labile in the genus. As defined morphologically, species of Fontinalis are nonmonophyletic for both nr- and cpDNA sequences and populations of some morphological taxa are separated in widely divergent clades. Molecular evidence suggests that at least some morphospecies are artificial, defined by convergent leaf forms. The weight of the evidence indicates that F. antipyretica is positively paraphyletic, with European populations more closely related to (i.e., share a more recent common ancestor with) European endemic species than to North American populations that are morphologically conspecific. North American populations are more closely related to North American endemic species.  相似文献   

8.
Systematic relationships among monarch flycatchers (genus Monarcha) are poorly understood despite dramatic patterns of morphological differentiation that have long attracted the attention of evolutionary biologists. With sequence data from the mitochondrial ND2 gene and Control Region, we produced a phylogenetic hypothesis for evolutionary relationships within Monarcha and among the biogeographically complex Solomon Island endemics. Outgroup analyses contradicted monophyly of the genus by imbedding a representative of the genus Clytorhynchus within one of two major clades recovered within Monarcha. These two monarch clades generally correspond with ecological and morphological distinctions, suggesting the genus may warrant revision pending the inclusion of taxa currently allied with Clytorhynchus (e.g., Neolalage spp.). Maximum likelihood reconstructions support monophyletic groupings of the two endemic Solomon Island monarch radiations, however, two currently recognized superspecies (Monarcha manadensis and M. melanopsis) were polyphyletic and paraphyletic, respectively. Interestingly, molecular and morphological differentiation were strikingly decoupled among several Solomon Island endemics and between migratory and non-migratory forms of Monarcha trivirgatus in eastern Australia, suggesting morphological evolution has masked the true history of speciation in these groups. This initial phylogeny provides a novel platform for ongoing exploration of the history underlying dramatic patterns of geographic variation among tropical Pacific flycatchers.  相似文献   

9.
The complete mitochondrial genome of Flustrellidra hispida (Bryozoa, Ctenostomata, Flustrellidridae) was sequenced using a transposon-mediated approach. All but one of the 36 genes were identified (trnS2). The genome is 13,026 bp long, being one of the smallest metazoan mitochondrial genomes sequenced to date with a unique gene order when compared to other Metazoa. The genome has an overall AT richness of 59.4%. We found seven regions of overlaps between tRNAs and protein-coding genes ranging from 2 to 11 nt, and seven regions of overlap between tRNAs, ranging from 1 to 8 nt, resulting in a total number of 46 overlapping nucleotides. Genes nad4, cox2, atp8, and nad3 are terminated by the abbreviated stop codon T and cytb is suggested to terminate on (ACT)AA; we postulate that mRNA editing is required to remove AC for TAA to be functional in terminating translation. Phylogenetic analysis of nucleotide and amino acid data place Flustrellidra in the Lophotrochozoa. DNA for this study originated from two populations resulting in a contig consisting of multiple haplotypes. Twenty-seven SNP sites were detected, the majority occurring in cox1 and nad5. With cox1 already established as a marker in bryozoan studies, we advocate the further testing of nad5.  相似文献   

10.
11.
Phylogenetic relationships within Collembola were determined through the cladistic analysis of 131 morphological characters and 67 exemplar taxa representing the major families of the group, with special emphasis on Poduromorpha. The results show that the order Poduromorpha is monophyletic and the sister group to the remaining Collembola, with Entomobryomorpha monophyletic and the sister group to the clade Neelipleona + Symphypleona. In Entomobryomorpha, Actaletidae is the sister group of the remaining families. In Poduromorpha, Tullbergiinae is monophyletic as well as Onychiurinae and the group Tetrodontophorinae + Onychiurinae which is the sister group of the remaining Poduromorpha; Tetrodontophorinae is paraphyletic; Onychiuridae is polyphyletic; Isotogastruridae is not an intermediate between Poduromorpha and Entomobryomorpha, it is the sister group of Tullbergiinae; Odontellidae is monophyletic and the sister group to the clade Neanuridae + Brachystomellidae; in Neanuridae, Frieseinae and the group Pseudachorutinae + Morulinae + Neanurinae are monophyletic; Morulinae is the sister group of Neanurinae; Pseudachorutinae is paraphyletic; Hypogastruridae is polyphyletic; Podura aquatica (Poduridae) is not 'primitive', it clusters with the genera Xenylla and Paraxenylla in Hypogastruridae. On the basis of these relationships and the position of the aquatic species, the most parsimonious hypothesis is a terrestrial edaphic origin for the springtails.  相似文献   

12.
We present a comprehensively sampled three‐gene phylogeny of the monophyletic Forcipulatacea, one of three major lineages within the crown‐group Asteroidea. We present substantially more Southern Hemisphere and deep‐sea taxa than were sampled in previous molecular studies of this group. Morphologically distinct groups, such as the Brisingida and the Zoroasteridae, are upheld as monophyletic. Brisingida is supported as the derived sister group to the Asteriidae (restricted), rather than as a basal taxon. The Asteriidae is paraphyletic, and is broken up into the Stichasteridae and four primary asteriid clades: (1) a highly diverse boreal clade, containing members from the Arctic and sub‐Arctic in the Northern Hemisphere; (2) the genus Sclerasterias; (3) and (4) two sister clades that contain asteriids from the Antarctic and pantropical regions. The Stichasteridae, which was regarded as a synonym of the Asteriidae, is resurrected by our results, and represents the most diverse Southern Hemisphere forcipulatacean clade (although two deep‐sea stichasterid genera occur in the Northern Hemisphere). The Labidiasteridae is artificial, and should be synonymized into the Heliasteridae. The Pedicellasteridae is paraphyletic, with three separate clades containing pedicellasterid taxa emerging among the basal Forcipulatacea. Fossils and timing estimates from species‐level phylogeographic studies are consistent with prior phylogenetic hypotheses for the Forcipulatacea, suggesting diversification of basal taxa in the early Mesozoic, with some evidence for more widely distributed ranges from Cretacous taxa. Our analysis suggests a hypothesis of an older fauna present in the Antarctic during the Eocene, which was succeeded by a modern Antarctic fauna that is represented by the recently derived Antarctic Asteriidae and other forcipulatacean lineages. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 646–660.  相似文献   

13.
The tribe Arctotideae (African Daisies), of the flowering plant family Compositae (Asteraceae), is a diverse and interesting group with a primarily southern African distribution (ca. 13 genera, 215 species) and many species in the Cape Floristic Region. It is divided into two subtribes: Arctotidinae (ca. 5 genera, 85 species) and Gorteriinae (ca. 8 genera, 130 species). The monophyly of the genera within the subtribe Gorteriinae and their relationship to one another was investigated using 71 samples/212 sequences including 64/141 of which are newly reported from three phylogenetic markers, two from chloroplast DNA (trnL-F and ndhF) and one from the nuclear genome (ITS). The outgroup was composed of seven members from the sister subtribe. Results show the subtribe Gorteriinae to be divided into three monophyletic groups, the Gazania-Hirpicium-Gorteria group, the Didelta group, and the Berkheya-Cullumia group. Within these three groups are 13 sub-groups, one of which has sub-clades. The genus Berkheya Ehrh. is paraphyletic, falling into five different sub-groups. The two monotypic genera, Cuspidia and Heterorhachis are not nested within any of the Berkheya clades. Hirpicium and Cullumia each have most of their taxa in a monophyletic group, but they also have one or two taxa associated with other clades. Four of the five sub-groups of Berkheya have morphologically recognizable shared characters, such as habit and spines that have been recognized by past studies. However, the grouping of one species with Didelta is difficult to explain. Support for the major clades and most of the sub-groups is strong but the relationships among some of the terminal taxa are variable.  相似文献   

14.
Direct evidence of competition is seldom available from the fossil record. Overgrowth relationships of encrusting marine organisms constitute an exception but have previously been reported in only temporally and geographically local occurrences. Results of overgrowths between members of two bryozoan clades, the Cyclostomata and the Cheilostomata, have been compiled for faunas distributed through the past 100 Myr. The cheilostomes have consistendy out-competed the cyclostomes, with approximately 66% overgrowdi success through the entire interval. This difference in success in direct interactions along with the Mid-Cretaceous rapid radiation of cheilostomes is interpreted as a factor in the Mid- to Late Cretaceous reversal from the previous diversification to stasis or gradual decline of cyclostome diversity.  相似文献   

15.
The phylogeny of the Piscicolidae was analysed from combined 18S rDNA, cytochrome c oxidase subunit I (CO-I), nicotinamide adenine dinucleotide dehydrogenase subunit I (ND-I) and morphological data using parsimony. A worldwide distribution of Piscicolidae was represented for the first time. While the family Piscicolidae was supported as a monophyletic group, the traditional subfamilies based on morphology were not supported. The Platybdellinae was polyphyletic and formed four distinct clades, and Bathybdella sawyeri did not group with any other platybdellins. The Piscicolinae was also polyphyletic, also forming four distinct clades. The pontobdellin genus Stibarobdella was shown to be the basal taxon within the Piscicolidae; however, the Pontobdellinae was found to be paraphyletic if Oxytonostoma was included. The genera Aestabdella , Austrobdella, and Malmiana were found to be paraphyletic; the genera Calliobdella, Cystobranchus, and Platybdella were found to be polyphyletic. The species Myzobdella lugubris was not found to be monophyletic. It is proposed that Oxytonostoma be transferred out of the Pontobdellinae, that Aestabdella be synonymized with Pterobdella , that Calliobdella vivida be returned to Cystobranchus , that Gonimosobdella be synonymized with Cystobranchus , and that Piscicolaria be synonymized with Myzobdella . The synonymy of Malmiana and Heptacyclus is confirmed, with Heptacyclus having priority. Piscicola milneri is confirmed to be a separate species from Piscicola geometra .  相似文献   

16.
Tordylium is a medium‐sized genus characterized by an annual habit, 1–3‐pinnate leaves, dorsally compressed mericarps, and thickened mericarp margins. Eighteen Tordylium species occur in Turkey, of which seven are endemic. Although the morphology of the genus is well known, evolutionary relationships among its species have never been evaluated. In this study, phylogenetic relationships within Tordylium are investigated using parsimony analysis based on morphological data from 17 ingroup and 15 outgroup taxa from Turkey. The results indicate that Tordylium is paraphyletic due to the inclusion of Ormosciadium. Further, it suggests that Hasselquistia, Condylocarpus and Ainsworthia are nested within Tordylium, confirming their current taxonomic treatment as synonyms. Within the paraphyletic Tordylium, two major clades are apparent, but these clades are not compatible with the current sub‐generic classification. Tordylium lanatum, T. aegyptiacum and T. elegans, which have dimorphic mericarps, form a monophyletic subclade. In addition, it is suggested that T. aegaeum should be accepted as a distinct species rather than as a synonym of T. pestalozzae.  相似文献   

17.
Lichen-forming ascomycetes exhibit often complex morphologies of the vegetative thallus that are usually not found in non-lichenized fungi. This includes the thallus organization and appendical structures associated with the main thallus, such as cilia and rhizines. Such morphological characters are widely employed in the taxonomy of parmelioid lichens, especially at generic level. Within parmelioid lichens, several monophyletic groups can be distinguished, the Hypotrachyna clade being one of them, which includes mostly tropical taxa. In this first molecular study focused specifically on the Hypotrachyna clade, we used maximum parsimony and Bayesian analyses of a combined data set of nuclear ITS and mitochondrial SSU rDNA sequences to (1) test the monophyly of genera presently accepted within the clade and (2) evaluate the phylogenetic value of the morphological characters used to circumscribe genera in parmelioid lichens. Out of the 89 mtSSU and 88 nuITS sequences included in the present study, 121 sequences were newly obtained. Our results show that the taxa within the clade fall into two major groups and that the genus Hypotrachyna is polyphyletic. Everniastrum and Parmelinopsis are nested within Hypotrachyna sensu stricto, the latter being also polyphyletic. Bulbothrix is paraphyletic with Parmelinella nested within and is basal to the second major Hypotrachyna clade. Monophylies of Bulbothrix and Hypotrachyna are significantly rejected. The phylogenetic analysis demonstrates that morphological characters currently used to circumscribe genera in parmelioid lichens, such as cortical anatomy, lobe configuration, cilia, and rhizines have been overestimated and have only minor value in identifying monophyletic groups.  相似文献   

18.
Abstract— A matrix of 41 Embiid taxa (representing the 8 formally recognized families of the Order) and 36 characters were cladistically analysed as a first attempt for understanding the higher classification of the Order Embioptera. The resulting trees were rooted with Clothodidae as the sister group of the other Embioptera. The results suggest that the current classification contains several artificial groups. With the rooting used, only Anisembiidae and Australembiidae are monophyletic. Embiidae is polyphyletic, as Australembiidae+ Notoligotomidae, Enveja (incertae sedis) and Oligotomidae+Teratembiidae appear within Embiidae, and the "embiid" Microembia appears within Notoligotomidae. Oligotomidae is paraphyletic in terms of Teratembiidae. Four of the genera included in the analysis are paraphyletic: Mesembia, Chelicerca (in terms of Dactylocerca and Pelorembia ), Aposthonia (in terms of Oligotoma ), and Metoligotoma (in terms of Australembia ). Pelorembia and Dactylocerca are synonymized with Chelicerca .  相似文献   

19.
Phylogenetic analyses of 46 species of Iris, representing all subgenera and all sections except Regelia, Brevituba, and Monolepis, utilized matK gene and trnK intron sequence data. Sequence data show that Iris is paraphyletic because Belamcanda chinensis is resolved within the genus. The two largest subgenera, Iris and Limniris, are both resolved as polyphyletic. With the removal of section Hexapogon, subgenus Iris is weakly supported as monophyletic. Relationships within subgenus Limniris are more complex with the subgenus as currently circumscribed representing eight independent origins among the species included in this study. Several potential monophyletic groups are identified including subgenus Scorpiris, series Spuria (subgenus Limniris section Limniris), and a clade of section Limniris species from North America and Asia.  相似文献   

20.
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