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1.
A phylogenetic analysis of Neuroptera using thirty‐six predominantly morphological characters of adults and larvae is presented. This is the first computerized cladistic analysis at the ordinal level. It included nineteen species representing seventeen families of Neuroptera, three species representing two families (Sialidae and both subfamilies of Corydalidae) of Megaloptera, two species representing two families of Raphidioptera and as prime outgroup one species of a family of Coleoptera. Ten equally most parsimonious cladograms were found, of which one is selected and presented in detail. The results are discussed in light of recent results from mental phylogenetic cladograms. The suborders Nevrorthi‐ formia, Myrmeleontiformia and Hemerobiiformia received strong support, however Nevrorthiformia formed the adelphotaxon of Myrmeleontiformia + Hemerobiiformia (former sister group of Myrmeleontiformia only). In Myrmeleontiformia, the sister‐group relationships between Psychopsidae + Nemopteridae and Nymphidae + (Myrmeleontidae + Ascalaphidae) are corroborated. In Hemerobiiformia, Ithonidae + Polystoechotidae is confirmed as the sister group of the remaining families. Dilaridae + (Mantispidae + (Rhachiberothidae + Berothidae)), which has already been proposed, is confirmed. Chrysopidae + Osmylidae emerged as the sister group of a clade comprising Hemerobiidae + ((Coniopterygidae + Sisyridae) + (dilarid clade)). Despite the sister‐group relationship of Coniopterygidae + Sisyridae being only weakly supported, the position of Coniopterygidae within the higher Hemerobiiformia is corroborated. At the ordinal level, the analysis provided clear support for the hypothesis that Megaloptera + Neuroptera are sister groups, which upsets the conventional Megaloptera + Raphidioptera hypothesis.  相似文献   

2.
The first large‐scale, total‐evidence phylogeny of the owlflies (Neuroptera, Ascalaphidae) is presented. A combined morphological and molecular dataset was analysed under several analytical regimes for 76 exemplars of Myrmeleontiformia (Psychopsidae, Nymphidae, Nemopteridae, Myrmeleontidae, Ascalaphidae), including 57 of Ascalaphidae. At the subordinal level, the families were recovered in all analyses in the form Psychopsidae + (Nymphidae + (Nemopteridae + (Myrmeleontidae + Ascalaphidae). In the DNA‐only maximum‐likelihood analysis, Ascalaphidae were recovered as paraphyletic with respect to the Myrmeleontidae and the tribe Ululodini. In both the parsimony and Bayesian total‐evidence analyses, however, the latter with strong support, traditional Ascalaphidae were recovered as monophyletic, and in the latter, Stilbopteryginae were placed as the immediate sister group. The long‐standing subfamilies Haplogleniinae and Ascalaphinae were not recovered as monophyletic in any analysis, nor were several of the included tribes of non‐ululodine Ascalaphinae. The Ululodini were monophyletic and well supported in all analyses, as were the New World Haplogleniinae and, separately, the African/Malagasy Haplogleniinae. The remaining Ascalaphidae, collectively, were also consistently cohesive, but included a genus that until now has been placed in the Haplogleniinae, Protidricerus. Protidricerus was discovered to express a well‐developed pleurostoma, a feature previously only encountered in divided‐eye owlflies. The feature traditionally used to differentiate the Haplogleniinae and Ascalaphinae, the entire or divided eye, can no longer be regarded as a spot‐diagnostic synapomorphy to separate these groups within the family. A new subfamilial classification based on these results is proposed and includes the following five subfamilies: Albardiinae, Ululodinae, Haplogleniinae, Melambrotinae and Ascalaphinae. In addition, the monophyletic containing group (Myrmeleontidae + (Palparidae + (Stilbopterygidae + Ascalaphidae))) is elevated to the rank of superfamily, as Myrmeleontoidea, in order to accommodate much‐needed taxonomic and nomenclatural restructuring anticipated to occur within the Ascalaphidae in the future. A list of genera included in each subfamily of Ascalaphidae is provided.  相似文献   

3.
External and internal head structures of larvae of Nevrorthidae were described in detail. The results were compared to conditions found in other representatives of Neuroptera and the other two neuropterid orders. The cladistic analysis supported the monophyly of Neuroptera, Neuroptera exclusive of Nevrorthidae, Hemerobiiformia, and Myrmeleontiformia. Neuroptera exclusive of Nevrorthidae are supported by the formation of an undivided postmentum and the presence of cryptonephric Malpighian tubules. The highly specialized articulation of the neck (Rollengelenk) and the absence of a salivary duct are autapomorphies of Nevrorthidae. Ithonidae and Polystoechotidae form a clade and are the sister group of the remaining Hemerobiiformia, which are characterized by the complete lack of a gula and a terminal filament of the antenna. Within this lineage, a clade comprising Mantispidae, Dilaridae, Berothidae, and Rhachiberothidae is well supported. Larvae of Myrmeleontiformia are characterized by a complex transformation of head structures, with a hypostomal bridge, a small triangular gula, largely reduced maxillary grooves, and anteriorly shifted posterior tentorial grooves. The slender finger‐like mid‐dorsal apodeme is another autapomorphy of the group. Psychopsidae are placed as the sister group of the remaining Myrmeleontiformia, which are characterized by a conspicuous, protruding ocular region (often less distinct or even absent in Nemopteridae). Ascalaphidae are the sister group of Myrmeleontidae. Larvae of both families share the fusion of the tibia and tarsus in the hind leg. The larval characters analysed were not sufficient for full resolution of the myrmeleontiform and hemerobiiform lineages. The position of several families such as Osmylidae, Sisyridae, and Coniopterygidae remains uncertain. The results are in agreement with an aquatic ancestor of Neuroptera and secondarily acquired terrestrial habits within the lineage (Neuroptera exclusive of Nevrorthidae), and another invasion of the aquatic environment by Sisyridae. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 533–562.  相似文献   

4.
The first phylogenomic analysis of the antlions is presented, based on 325 genes captured using anchored hybrid enrichment. A concatenated matrix including 207 species of Myrmeleontoidea (170 Myrmeleontidae) was analysed under maximum likelihood and Bayesian inference. Both Myrmeleontidae (antlions) and Ascalaphidae (owlflies) were recovered as paraphyletic with respect to each other. The majority of the subfamilies traditionally assigned to both Myrmeleontidae and Ascalaphidae were also recovered as paraphyletic. By contrast, all traditional antlion tribes were recovered as monophyletic (except Brachynemurini), but most subtribes were found to be paraphyletic. When compared with the traditional classification of Myrmeleontidae, our results do not support the current taxonomy. Therefore, based on our phylogenomic results, we propose a new classification for the antlions, which synonymizes Ascalaphidae with Myrmeleontidae and divides the family into four subfamilies (Ascalaphinae, Myrmeleontinae, Dendroleontinae and Nemoleontinae) and 17 tribes. We also highlight the most pressing issues in antlion systematics and indicate taxa that need further taxonomic and phylogenetic attention. Finally, we present a comprehensive table placing all extant genera of antlions and owlflies in our new proposed classification, including details on the number of species, distribution and notes on the likely monophyly of each genus.  相似文献   

5.
Adephaga is the second largest suborder of beetles (Coleoptera) and they serve as important arthropod predators in both aquatic and terrestrial ecosystems. The suborder is divided into Geadephaga comprising terrestrial families and Hydradephaga for aquatic lineages. Despite numerous studies, phylogenetic relationships among the adephagan families and monophyly of the Hydradephaga itself remain in question. Here we conduct a comprehensive phylogenomic analysis of the suborder using ultraconserved elements (UCEs). This study presents the first in vitro test of a newly developed UCE probe set customized for use within Adephaga that includes both probes tailored specifically for the suborder, alongside generalized Coleoptera probes previously found to work in adephagan taxa. We assess the utility of the entire probe set, as well as comparing the tailored and generalized probes alone for reconstructing evolutionary relationships. Our analyses recovered strong support for the paraphyly of Hydradephaga with whirligig beetles (Gyrinidae) placed as sister to all other adephagan families. Geadephaga was strongly supported as monophyletic and placed sister to a clade composed of Haliplidae + Dytiscoidea. Monophyly of Dytiscoidea was strongly supported with relationships among the dytiscoid families resolved and strongly supported. Relationships among the subfamilies of Dytiscidae were strongly supported but largely incongruent with prior phylogenetic estimates for the family. The results of our UCE probe comparison showed that tailored probes alone outperformed generalized probes alone, as well as the full combined probe set (containing both types of probes), under decreased taxon sampling. When taxon sampling was increased, the full combined probe set outperformed both tailored probes and generalized probes alone. This study provides further evidence that UCE probe sets customized for a focal group result in a greater number of recovered loci and substantially improve phylogenomic analysis.  相似文献   

6.
A new genus and species of antlion‐like fossil lacewing, Guyiling jianboni gen. et sp.n. (Insecta: Neuroptera) are described based on a single specimen from the Yixian Formation (Liaoning Province, China; Early Cretaceous). The new taxon exhibits derived traits such as distally dilated antennae and well‐developed anterior Banksian line (known in Myrmeleontidae), but also genuine plesiomorphies (at the level of Myrmeleontiformia), such as the divergence of a distinct CuA1 stem from MP2 + CuA1 (forewing), and a basal origin of MA (diverging from RP + MA; both wing pairs). This combination is unique among the ‘Palaeoleontidae’, a group better considered as a paraphyletic assemblage of various stem‐Myrmeleontiformia. The wing morphology of the new species is considered in the light of a survey of wing venation topological homologies (and implied transformations) among several Neuroptera families. The survey includes a revision of the holotype of Leptolingia jurassica Ren (Grammolingiidae; Jiulongshan Formation, Daohugou locality, Inner Mongolia Autonomous Region, China; middle Jurassic). The forewing morphology of Guyiling jianboni gen. et sp.n. demonstrates that the fusion of MP2 with CuA, and the differentiation of CuA into two distinct main stems (namely CuA1 and CuA2) are traits shared with Myrmeleontidae and Ascalaphidae (and possibly Nemopteridae). However, the survey also demonstrates that a fusion of MP2 with CuA occurred repeatedly among Neuropterida, although by means of various modalities (namely translocation vs regular fusion). The ‘pectinate fusion’ of CuA(1) with MP2 [i.e. CuA1 has no distinct stem and emits successive branches from MP2 + CuA(1) partim] is a further step in this fusion, and occurred repeatedly as well (at least in the hind wings of Osmylidae and Nymphidae, and both fore‐ and hindwings of a sub‐group of Myrmeleontiformia including Myrmeleontidae and Ascalaphidae, and possibly Nemopteridae). It is anticipated that the current contribution will constitute useful background information for further studies, focusing on particular transformation cases, ideally including a documentation of intraspecific variation.  相似文献   

7.
Phylogenetic relationships within the diverse beetle superfamily Cucujoidea are poorly known. The Cerylonid Series (C.S.) is the largest of all proposed superfamilial cucujoid groups, comprising eight families and representing most of the known cucujoid species diversity. The monophyly of the C.S., however, has never been formally tested and the higher-level relationships among and within the constituent families remain equivocal. Here we present a phylogenetic study based on 18S and 28S rDNA for 16 outgroup taxa and 61 C.S. ingroup taxa, representing seven of the eight C.S. families and 20 of 39 subfamilies. We test the monophyly of the C.S., investigate the relationships among the C.S. families, and test the monophyly of the constituent families and subfamilies. Phylogenetic reconstruction of the combined data was achieved via standard static alignment parsimony analyses, Direct Optimization using parsimony, and partitioned Bayesian analysis. All three analyses support the paraphyly of Cucujoidea with respect to Tenebrionoidea and confirm the monophyly of the C.S. The C.S. families Bothrideridae, Cerylonidae, Discolomatidae, Coccinellidae and Corylophidae are supported as monophyletic in all analyses. Only the Bayesian analysis recovers a monophyletic Latridiidae. Endomychidae is recovered as polyphyletic in all analyses. Of the 14 subfamilies with multiple terminals in this study, 11 were supported as monophyletic. The corylophid subfamily Corylophinae and the coccinellid subfamilies Chilocorinae and Scymninae are recovered as paraphyletic. A sister grouping of Anamorphinae+Corylophidae is supported in all analyses. Other taxonomic implications are discussed in light of our results.  相似文献   

8.
In the holometabolous insect order Neuroptera (lacewings), the cosmopolitan Myrmeleontidae (antlions) are the most species-rich family, while the closely related Nymphidae (split-footed lacewings) are a small endemic family from the Australian-Malesian region. Both families belong to the suborder Myrmeleontiformia, within which controversial hypotheses on the interfamilial phylogenetic relationships exist. Herein, we describe the complete mitochondrial (mt) genomes of an antlion (Myrmeleon immanis Walker, 1853) and a split-footed lacewing (Nymphes myrmeleonoides Leach, 1814), representing the first mt genomes for both families. These mt genomes are relatively small (respectively composed of 15,799 and 15,713 bp) compared to other lacewing mt genomes, and comprise 37 genes (13 protein coding genes, 22 tRNA genes and two rRNA genes). The arrangement of these two mt genomes is the same as in most derived Neuroptera mt genomes previously sequenced, specifically with a translocation of trnC. The start codons of all PCGs are started by ATN, with an exception of cox1, which is ACG in the M. immanis mt genome and TCG in N. myrmeleonoides. All tRNA genes have a typical clover-leaf structure of mitochondrial tRNA, with the exception of trnS1(AGN). The secondary structures of rrnL and rrnS are similar with those proposed insects and the domain I contains nine helices rather than eight helices, which is common within Neuroptera. A phylogenetic analysis based on the mt genomic data for all Neuropterida sequenced thus far, supports the monophyly of Myrmeleontiformia and the sister relationship between Ascalaphidae and Myrmeleontidae.  相似文献   

9.
A large‐scale phylogenetic study is presented for Cucujoidea (Coleoptera), a diverse superfamily of beetles that historically has been taxonomically difficult. This study is the most comprehensive analysis of cucujoid taxa to date, with DNA sequence data sampled from eight genes (four nuclear, four mitochondrial) for 384 coleopteran taxa, including exemplars of 35 (of 37) families and 289 genera of Cucujoidea. Maximum‐likelihood analyses of these data present many significant relationships, some proposed previously and some novel. Tenebrionoidea and Lymexyloidea are recovered together and Cleroidea forms the sister group to this clade. Chrysomeloidea and Curculionoidea are recovered as sister taxa and this clade (Phytophaga) forms the sister group to the core Cucujoidea (Cucujoidea s.n .). The nitidulid series is recovered as the earliest‐diverging core cucujoid lineage, although the earliest divergences among core Cucujoidea are only weakly supported. The cerylonid series (CS) is recovered as monophyletic and is supported as a major Cucujiform clade, sister group to the remaining superfamilies of Cucujiformia. Currently recognized taxa that were not recovered as monophyletic include Cucujoidea, Endomychidae, Cerylonidae and Bothrideridae. Biphyllidae and Byturidae were recovered in Cleroidea. The remaining Cucujoidea were recovered in two disparate major clades: one comprising the nitidulid series + erotylid series + Boganiidae and Hobartiidae + cucujid series, and the other comprising the cerylonid series. Propalticidae are recovered within Laemophloeidae. The cerylonid series includes two major clades, the bothriderid group and the coccinellid group. Akalyptoischiidae are recovered as a separate clade from Latridiidae. Eupsilobiinae are recovered as the sister taxon to Coccinellidae. In light of these findings, many formal changes to cucujiform beetle classification are proposed. Biphyllidae and Byturidae are transferred to Cleroidea. The cerylonid series is formally recognized as a new superfamily, Coccinelloidea stat.n. Current subfamilies elevated (or re‐elevated) to family status include: Murmidiidae stat.n. , Teredidae stat.n. , Euxestidae stat.n. , Anamorphidae stat.rev. , Eupsilobiidae stat.n. , and Mycetaeidae stat.n. The following taxa are redefined and characterized: Cleroidea s.n. , Cucujoidea s.n. , Cerylonidae s.n. , Bothrideridae s.n. , Endomychidae s.n. A new subfamily, Cyclotominae stat.n. , is described. Stenotarsinae syn.n. is formally subsumed within a new concept of Endomychinae s.n.  相似文献   

10.
A parsimony‐based phylogenetic analysis of eighty‐three morphological characters of adults and immatures of seventy representatives of the tribes and subfamilies of Membracidae and two outgroup taxa was conducted to evaluate the status and relationships of these taxa. Centrotinae apparently gave rise to Nessorhinini and Oxyrhachini (both formerly treated as subfamilies, now syn.n. and syn.reinst., respectively, of Centrotinae). In contrast to previous analyses, a clade comprising Nicomiinae, Centronodinae, Centrodontinae, and the unplaced genera Holdgatiella Evans, Euwalkeria Goding and Antillotolania Ramos was recovered, but relationships within this clade were not well resolved. Nodonica bispinigera, gen.n. and sp.n., is described and placed in Centrodontini based on its sister‐group relationship to a clade comprising previously described genera of this tribe. Membracinae and Heteronotinae were consistently monophyletic. Neither Darninae nor Smiliinae, as previously defined, was monophyletic on the maximally parsimonious cladograms, but constraining both as monophyletic groups required only one additional step. The monophyly of Stegaspidinae, including Deiroderes Ramos (unplaced in Membracidae), was supported on some but not all equally parsimonious cladograms. More detailed analyses of individual subfamilies, as well as morphological data on the undescribed immatures of several membracid tribes and genera, will be needed to elucidate relationships among tribes and genera. A key to the subfamilies and tribes is provided.  相似文献   

11.
Phylogeny of the Neuropterida (Insecta: Holometabola)   总被引:3,自引:0,他引:3  
The Neuropterida, with about 6500 known species — living fossils in a way — at the base of the Holometabola (as a sister group of the Coleoptera), comprise Raphidioptera (about 210 species, two families), Megaloptera (about 300 species, two families) and Neuroptera (6000 species, 17 families). Megaloptera + Neuroptera is argued vs. the traditional Raphidioptera + Megaloptera. Raphidioptera are undisputedly monophyletic. Monophyly of Megaloptera is the operational hypothesis, although occasionally questioned. Sucking tubes of the larvae are the most spectacular autapomorphy of Neuroptera. The construction of larval head capsules indicates three evolutionary lines: Nevrorthiformia, and Myrmeleontiformia + Hemerobiiformia. Traditional Myrmeleontiformia is Psychopsidae + (Nemopteridae + (Nymphidae + (Myrmeleontidae + Ascalaphidae))), the present approach is (Psychopsidae + Nemopteridae) + all other Myrmeleontiformia. Hemerobiiformia are based on the ‘maxillary head’ concept. The ithonid clade Ithonidae/Rapismatidae + Polystoechothidae and the dilarid clade Dilaridae + (Mantispidae + (Rhachiberothidae + Berothidae)) are based on robust criteria. Other relationships remain unclear: Hemerobiidae + Chrysopidae (on similarity) and the ‘early offshoot’ concept of coniopterygidae (on autapomorphies) should not be perpetuated. Chysopidae + Osmylidae and (Hemerobiidae + (Coniopterygidae + Sisyridae)) + dilarid clade are discussed. Aquatic larvae, regarded as independent apomorphies of megaloptera and neuropteran Nevrorthidae and Sisyridae for a long time, are re‐interpreted as a synapomorphy of Megaloptera + Neuroptera and thus plesiomorphic within these groups. Terrestrial larvae (with cryptonephry to solve osmotic problems) are consequently apomorphic. Aquatic Sisyridae with cryptonephry of a single malpighian tubule, is conflicting, but larvae may have become secondarily aquatic, after a terrestrial intermezzo.  相似文献   

12.
13.
The superfamilies of Elateriformia have been in a state of flux since their establishment. The recent classifications recognize Dascilloidea, Buprestoidea, Byrrhoidea and Elateroidea. The most problematic part of the elateriform phylogeny is the monophyly of Byrrhoidea and the relationships of its families. To investigate these issues, we merged more than 500 newly produced sequences of 18S rRNA, 28S rRNA, rrnL mtDNA and cox1 mtDNA for 140 elateriform taxa with data from GenBank. We assembled an all‐taxa (488 terminals) and a pruned data set, which included taxa with full fragment representation (251 terminals); both were aligned in various programs and analysed using maximum‐likelihood criterion and Bayesian inference. Most analyses recovered monophyletic superfamilies and broadly similar relationships; however, we obtained limited statistical support for the backbone of trees. Dascilloidea were sister to the remaining Elateriformia, and Elateroidea were sister to the clade of byrrhoid lineages including Buprestoidea. This clade mostly consisted of four major lineages, that is (i) Byrrhidae, (ii) Dryopidae + Lutrochidae, (iii) Buprestoidea (Schizopodidae sister to Buprestidae) and (iv) a clade formed by the remaining byrrhoid families. Buprestoidea and byrrhoid lineages, with the exception of Byrrhidae and Dryopidae + Lutrochidae, were usually merged into a single clade. Most byrrhoid families were recovered as monophyletic. Callirhipidae and Eulichadidae formed independent terminal lineages within the Byrrhoidea–Buprestoidea clade. Paraphyletic Limnichidae were found in a clade with Heteroceridae and often also with Chelonariidae. Psephenidae, represented by Eubriinae and Eubrianacinae, never formed a monophylum. Ptilodactylidae were monophyletic only when Paralichas (Cladotominae) was excluded. Elmidae regularly formed a clade with a bulk of Ptilodactylidae; however, elmid subfamilies (Elminae and Larainae) were not recovered. Despite the densest sampling of Byrrhoidea diversity up to date, the results are not statistically supported and resolved only a limited number of relationships. Furthermore, questions arose which should be considered in the future studies on byrrhoid phylogeny.  相似文献   

14.
Phylogenetic relationships among genera of pigeons and doves (Aves, Columbiformes) have not been fully resolved because of limited sampling of taxa and characters in previous studies. We therefore sequenced multiple nuclear and mitochondrial DNA genes totaling over 9000 bp from 33 of 41 genera plus 8 outgroup taxa, and, together with sequences from 5 other pigeon genera retrieved from GenBank, recovered a strong phylogenetic hypothesis for the Columbiformes. Three major clades were recovered with the combined data set, comprising the basally branching New World pigeons and allies (clade A) that are sister to Neotropical ground doves (clade B), and the Afro-Eurasian and Australasian taxa (clade C). None of these clades supports the monophyly of current families and subfamilies. The extinct, flightless dodo and solitaires (Raphidae) were embedded within pigeons and doves (Columbidae) in clade C, and monophyly of the subfamily Columbinae was refuted because the remaining subfamilies were nested within it. Divergence times estimated using a Bayesian framework suggest that Columbiformes diverged from outgroups such as Apodiformes and Caprimulgiformes in the Cretaceous before the mass extinction that marks the end of this period. Bayesian and maximum likelihood inferences of ancestral areas, accounting for phylogenetic uncertainty and divergence times, respectively, favor an ancient origin of Columbiformes in the Neotropical portion of what was then Gondwana. The radiation of modern genera of Columbiformes started in the Early Eocene to the Middle Miocene, as previously estimated for other avian groups such as ratites, tinamous, galliform birds, penguins, shorebirds, parrots, passerine birds, and toucans. Multiple dispersals of more derived Columbiformes between Australasian and Afro-Eurasian regions are required to explain current distributions.  相似文献   

15.
The tubificid clitellates are a common component in the freshwater bottom fauna and are also the most abundant oligochaete group in marine habitats. There are over 800 described species classified in six subfamilies; Tubificinae, Limnodriloidinae, Rhyacodrilinae, Telmatodrilinae, Phallodrilinae, and Naidinae. In this study we examine the phylogenetic relationships in Tubificidae using a combination of mitochondrial 16S rDNA and nuclear 18S rDNA sequence data. Sequences were obtained from five outgroup and 56 ingroup taxa, including five of the six subfamilies of Tubificidae. The data were analysed by maximum parsimony and Bayesian inference. The resulting tree topologies are virtually without conflict. Several associations traditionally recognized within the family Tubificidae are supported, in the Bayesian analysis including a sister group relationship between Tubificinae and Limnodriloidinae. The results also indicate that Rhyacodrilinae is polyphyletic--some of its members (Heterodrilus spp.) fall into a clade with Phallodrilinae, all other groups with Naidinae. Naidinae is also polyphyletic with two rhyacodriline genera, Monopylephorus and Ainudrilus, nested within. Most of the tubificid genera included in the study are supported as monophyletic; however, Tubifex and Limnodriloides are refuted, and Tubificoides is unresolved from other tubificine taxa.  相似文献   

16.
Mygalomorph spiders, which include the tarantulas, trapdoor spiders, and their kin, represent one of three main spider lineages. Mygalomorphs are currently classified into 15 families, comprising roughly 2500 species and 300 genera. The few published phylogenies of mygalomorph relationships are based exclusively on morphological data and reveal areas of both conflict and congruence, suggesting the need for additional phylogenetic research utilizing new character systems. As part of a larger combined evidence study of global mygalomorph relationships, we have gathered approximately 3.7 kb of rRNA data (18S and 28S) for a sample of 80 genera, representing all 15 mygalomorph families. Taxon sampling was particularly intensive across families that are questionable in composition-Cyrtaucheniidae and Nemesiidae. The following primary results are supported by both Bayesian and parsimony analyses of combined matrices representing multiple 28S alignments: (1) the Atypoidea, a clade that includes the families Atypidae, Antrodiaetidae, and Mecicobothriidae, is recovered as a basal lineage sister to all other mygalomorphs, (2) diplurids and hexathelids form a paraphyletic grade at the base of the non-atypoid clade, but neither family is monophyletic in any of our analyses, (3) a clade consisting of all sampled nemesiids, Microstigmata and the cyrtaucheniid genera Kiama, Acontius, and Fufius is consistently recovered, (4) other sampled cyrtaucheniids are fragmented across three separate clades, including a monophyletic North American Euctenizinae and a South African clade, (5) of the Domiothelina, only idiopids are consistently recovered as monophyletic; ctenizids are polyphyletic and migids are only weakly supported. The Domiothelina is not monophyletic. The molecular results we present are consistent with more recent hypotheses of mygalomorph relationship; however, additional work remains before mygalomorph classification can be formally reassessed with confidence-increased taxonomic sampling and the inclusion of additional character systems (more genes and morphology) are required.  相似文献   

17.
Current taxonomy of the Bryopsidales recognizes eight families; most of which are further categorized into two suborders, the Bryopsidineae and Halimedineae. This concept was supported by early molecular phylogenetic analyses based on rRNA sequence data, but subsequent cladistic analyses of morphological characters inferred monophyly in only the Halimedineae. These conflicting results prompted the current analysis of 32 taxa from this diverse group of green algae based on plastid‐encoded RUBISCO large subunit (rbcL) gene sequences. Results of these analyses suggested that the Halimedineae and Bryopsidineae are distinct monophyletic lineages. The families Bryopsidaceae, Caulerpaceae, Codiaceae, Derbesiaceae, and Halimediaceae were inferred as monophyletic, however the Udoteaceae was inferred as non‐monophyletic. The phylogenetic position of two taxa with uncertain subordinal affinity, Dichotomosiphon tuberosus Lawson and Pseudocodium floridanum Dawes & Mathieson, were also inferred. Pseudocodium was consistently placed within the halimedinean clade suggesting its inclusion into this suborder, however familial affinity was not resolved. D. tuberosus was the inferred sister taxon of the Halimedineae based on analyses of rbcL sequence data and thus a possible member of this suborder.  相似文献   

18.
Skinks are the largest family of lizards and are found worldwide in a diversity of habitats. One of the larger and more poorly studied groups of skinks includes members of the subfamily Scincinae distributed in sub-Saharan Africa. Sub-Saharan African scincines are one of the many groups of lizards that show limb reduction and loss, and the genus Scelotes offers an excellent opportunity to look at limb loss in a phylogenetic context. Phylogenetic relationships were reconstructed for a total of 52 taxa representing all subfamilies of skinks as well as other Autarchoglossan families using sequence from six gene regions including; 12S, 16S, and cytochrome b (mitochondrial), as well as alpha-Enolase, 18S, and C-mos (nuclear). The family Scincidae is recovered as monophyletic and is the sister taxon to a (Cordylidae+Xantusiidae) clade. Within skinks the subfamily Acontinae is monophyletic and sister group to all remaining skinks. There is no support for the monophyly of the subfamilies Lygosominae and Scincinae, but sub-Saharan African scincines+Feylinia form a well supported monophyletic group. The monophyly of Scelotes is confirmed, and support is found for two geographic groups within the genus. Reconstructions of ancestral states for limb and digital characters show limited support for the reversal or gain of both digits and limbs, but conservative interpretation of the results suggest that limb loss is common, occurring multiple times throughout evolutionary history, and is most likely not reversible.  相似文献   

19.
We assessed phylogenetic relationships within Serpulidae (including Spirorbinae) using parsimony and Bayesian analyses of 18S rDNA, the D1 and D9−D10 regions of 28S rDNA, and 38 morphological characters. In total, 857 parsimony informative characters were used for 31 terminals, 29 serpulids and sabellid and sabellariid outgroups. Following ILD assessment the two sequence partitions and morphology were analysed separately and in combination. The morphological parsimony analysis was congruent with the results of the 2003 preliminary analysis by Kupriyanova in suggesting that a monophyletic Serpulinae and Spirorbinae form a clade, while the remaining serpulids form a basal grade comprising what are normally regarded as Filograninae. Bremer support values were, however, quite low throughout. In contrast, the combined analyses of molecular and morphological data sets provided highly resolved and well-supported trees, though with some conflict when compared to the morphology-only analysis. Spirorbinae was recovered as a sister group to a monophyletic group comprising both 'filogranin' taxa ( Salmacina , Filograna , Protis , and Protula ) and 'serpulin' taxa such as Chitinopoma , Metavermilia , and Vermiliopsis . Thus the traditionally formulated subfamilies Serpulinae and Filograninae are not monophyletic. This indicates that a major revision of serpulid taxonomy is needed at the more inclusive taxonomic levels. We refrain from doing so based on the present analyses since we feel that further taxon sampling and molecular sequencing are required. The evolution of features such as the operculum and larval development are discussed.  相似文献   

20.
Neogastropoda, a highly diversified group of predatory marine snails, has often been contradicted in molecular phylogenetic studies. This is partly the consequence of limited neogastropod taxa or outgroups analyzed or insufficient gene sequences employed. This paper reports the most extensive molecular study of the group published to date with increased neogastropod taxa, multiple representatives of caenogastropod outgroups, and additional gene sequences. Data were collected from the entire 18S rRNA, histone H3, and three partial mitochondrial genes. Maximum parsimony, maximum likelihood and Bayesian analyses were conducted. In the caenogastropod phylogenetic framework, Hypsogastropoda was contradicted owing to the inclusion of Cerithioidea. Contrary to previous molecular studies, all the results recovered Neogastropoda as a monophyletic group, which confirms the monophyly of Neogastropoda and the validity of morphological synapomorphies that usually define Neogastropoda as monophyletic. Tonnoidea was shown to be paraphyletic with respect to Ficidae, and together this group formed a monophyletic clade as the sister group to Neogastropoda, which supported the “high mesogastropod” hypothesis of the origin of Neogastropoda. All neogastropod families were strongly supported except Buccinidae, Turridae and Cancellariidae. Our results shed light on the status of Neogastropoda, a controversial group, within Caenogastropoda.  相似文献   

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