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1.
Coloniality in the phylum Rotifera 总被引:3,自引:1,他引:2
Robert Lee Wallace 《Hydrobiologia》1987,147(1):141-155
Coloniality in the phylum Rotifera is defined and reviewed. Only two families of rotifers contain truly colonial forms: Flosculariidae and Conochilidae (order Gnesiotrocha, suborder Flosculariacea). Most species form intraspecific colonies ranging in size from a few to about 200 individuals, but species that produce enormous colonies (> 1000 individuals) are also known. All seven genera of the Flosculariidae contain species that form colonies to widely varying degrees (Beauchampia, Floscularia, Lacinularia, Limnias, Octotrocha, Ptygura, Sinantherina). All four species of the monogenetic Conochilidae (Conochilus) are colonial, but two species form colonies of only an adult and a few young. At least one other family (Philodinidae; Bdelloida) contains a species that exhibits a form of coloniality (Philodina megalotrocha). Two hypotheses that attempt to explain the adaptive significance of coloniality (Energetic Advantage and Predatory Avoidance) are reviewed and new information concerning the former is presented. Evolution of coloniality is discussed briefly. 相似文献
2.
Samuli Lehtonen Maarten J. M. Christenhusz Daniel Falck 《Botanical journal of the Linnean Society. Linnean Society of London》2016,182(4):825-867
Ranunculaceae are a nearly cosmopolitan plant family with the highest diversity in northern temperate regions and with relatively few representatives in the tropics. As a result of their position among the early diverging eudicots and their horticultural value, the family is of great phylogenetic and taxonomic interest. Despite this, many genera remain poorly sampled in phylogenetic studies and taxonomic problems persist. In this study, we aim to clarify the infrageneric relationships of Clematis by greatly improving taxon sampling and including most of the relevant subgeneric and sectional types in a simultaneous dynamic optimization of phenotypic and molecular data. We also investigate how well the available data support the hypothesis of phylogenetic relationships in the family. At the family level, all five currently accepted subfamilies are resolved as monophyletic. Our analyses strongly imply that Anemone s.l. is a grade with respect to the Anemoclema + Clematis clade. This questions the recent sinking of well‐established genera, including Hepatica, Knowltonia and Pulsatilla, into Anemone. In Clematis, 12 clades conceptually matching the proposed sectional division of the genus were found. The taxonomic composition of these clades often disagrees with previous classifications. Phylogenetic relationships between the section‐level clades remain highly unstable and poorly supported and, although some patterns are emerging, none of the proposed subgenera is in evidence. The traditionally recognized and horticulturally significant section Viorna is both nomenclaturally invalid and phylogenetically unsupported. Several other commonly used sections are likewise unjustified. Our results provide a phylogenetic background for a natural section‐level classification of Clematis. 相似文献
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4.
In this study, we successfully assembled the complete mitochondrial genome of the Amu Darya sturgeon Pseudoscaphirhynchus kaufmanni. Based on this mitochondrial genome and previously published mitochondrial genomes of members of the Acipenseridae family, we assessed the phylogenetic position of P. kaufmanni using maximum likelihood and Bayesian inference for phylogeny reconstruction. The resultant phylogenetic trees were well-resolved, with congruence between different phylogenetic methods. This robust phylogenetic analysis elucidated the relationship among the four acipenserid genera and strongly supported the division of the family into three main clades. Evaluation of molecular phylogeny using maximum likelihood and Bayesian analysis led to the following conclusions: (a) the most basal position within the Acipenseridae remains in the clade containing Acipenser oxyrinchus and Acipenser sturio; (b) the genus Scaphirhynchus belongs to the Atlantic clade and is a sister group of the remaining species of the clade; and (c) the close relationship between P. kaufmanni and Acipenser stellatus is well supported. 相似文献
5.
Large‐scale molecular phylogeny of metallic wood‐boring beetles (Coleoptera: Buprestoidea) provides new insights into relationships and reveals multiple evolutionary origins of the larval leaf‐mining habit
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The family Buprestidae (jewel beetles or metallic wood‐boring beetles), contains nearly 15 000 species in 522 genera. Together with the small family Schizopodidae (seven species, three genera), they form the superfamily Buprestoidea. Adult Buprestoidea feed on flowers or foliage, whereas larvae are mostly internal feeders, boring in roots or stems, or mining the leaves of woody or herbaceous plants. The subfamilial and tribal classification of Buprestoidea remains unsettled, with substantially different schemes proposed by different workers based on morphology. Here we report the first large‐scale molecular phylogenetic study of the superfamily Buprestoidea based on data from four genes for 141 ingroup species. We used these data to reconstruct higher‐level relationships and to assess the current classification and the origins of the larval leaf‐mining habit within Buprestoidea. In our analyses, the monophyly of Buprestoidea was strongly supported, as was the monophyly of Schizopodidae and its placement sister to Buprestidae. Our results are largely consistent with the generally accepted major lineages of buprestoids, including clearly‐defined agrilines, buprestines–chrysochroines and early‐branching julodines–polycestines. In addition to Schizopodidae, three of the six subfamilies were monophyletic in our study: Agrilinae, Julodinae and the monogeneric Galbellinae (Galbella). Polycestinae was monophyletic with the exception of the enigmatic Haplostethini. Chrysochroinae and Buprestinae were not monophyletic, but were recovered together in a large mixed clade along with Galbella. The interrelationships of Chrysochroinae and Buprestinae were not well resolved; however they were clearly polyphyletic, with chrysochroine genera falling into several different well‐supported clades otherwise comprising buprestine genera. All Agrilinae were contained in a single strongly supported clade. Coraebini were dispersed throughout Agrilinae, with strong nodal support for several clades representing subtribes. Neither Agrilini nor Tracheini were monophyletic. The leaf‐mining genus Paratrachys (Paratracheini) was recovered within the Acmaeoderioid clade, consistent with the current classification, and confirming the independent origins of leaf‐mining within Polycestinae and Agrilinae. Additionally, our results strongly suggest that the leaf‐mining agriline tribe Tracheini is polyphyletic, as are several of its constituent subtribes. External root feeding was likely the ancestral larval feeding habit in Buprestoidea. The apparent evolutionary transitions to internal feeding allowed access to a variety of additional plant tissues, including leaves. Interestingly, the several genera of leaf‐mining agrilines do not form a monophyletic group. Many of these genera are diverse and highly specialized, possibly indicating adaptive radiations. 相似文献
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7.
Weisrock DW Papenfuss TJ Macey JR Litvinchuk SN Polymeni R Ugurtas IH Zhao E Jowkar H Larson A 《Molecular phylogenetics and evolution》2006,41(2):368-383
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
8.
Phylogeny and classification of the Conochilidae (Rotifera, Monogononta, Flosculariacea) 总被引:3,自引:0,他引:3
To resolve several taxonomic problems within the family Conochilidae (Rotifera, Monogononta, Flosculariacea), we initiated a comparative study of the morphology in this and related taxa using samples collected from widely separated geographical regions. As part of this study, we paid special attention to trophal morphology using scanning electron microscopy. We also constructed and analysed a data matrix comprising 19 morphological characters of 11 taxa using cladistic methods to uncover all most-parsimonious trees. The results indicate that Conochilidae share a body form with Flosculariidae, but they possess a trophal structure which clearly differentiates them from all other Flosculariacea; thus, the diagnosis of the family Conochilidae is amended to incorporate morphological characters of the trophi. The analysis of our data matrix yielded a single, most-parsimonious tree. From the topology of that tree and our scanning electron microscopy observations, we propose the following: (1) the status of Conochilidae as a separate suborder of Flosculariacea is rejected; (2) taxonomic separation of Conochilus and Conochiloides as subgenera of Conochilus is confirmed; and (3) Lacinularia causeyae Vidrine, Mclaughlin & Willis, 1985 is reallocated to a new genus within the family Conochilide, Conochilopsis gen. nov., as Conochilopsis causeyae (Vidrine et al .) comb. nov. 相似文献
9.
Phylogenetic relationships among sloths (Mammalia, Xenarthra, Tardigrada): the craniodental evidence 总被引:3,自引:0,他引:3
TIMOTHY J. GAUDIN 《Zoological Journal of the Linnean Society》2004,140(2):255-305
This study is undertaken in order to evaluate specific hypotheses of relationship among extant and extinct sloths (Mammalia, Xenarthra, Tardigrada). Questions of particular interest include the relationship among the three traditional family groupings of extinct ground sloths and the monophyletic or diphyletic origin of the two genera of extant tree sloths. A computer‐based cladistic investigation of the phylogenetic relationships among 33 sloth genera is performed based upon 286 osteological characteristics of the skull, lower jaw, dentition and hyoid arch. Characters are polarized via comparisons with the following successive outgroups, all members of the supraordinal grouping Edentata: the Vermilingua, or anteaters; the Cingulata, or armadillos and glyptodonts; the Palaeanodonta; and the Pholidota, or pangolins. The results of the analysis strongly corroborate the diphyly of living tree sloths, with the three‐toed sloth Bradypus positioned as the sister‐taxon to all other sloths, and the two‐toed sloth Choloepus allied with extinct members of the family Megalonychidae. These results imply that the split between the two extant sloth genera is ancient, dating back perhaps as much as 40 Myr, and that the similarities between the two taxa, including their suspensory locomotor habits, present one of the most dramatic examples of convergent evolution known among mammals. The monophyly of the three traditional ground sloth families Megatheriidae, Megalonychidae and Mylodontidae is confirmed in the present study, and the late Miocene–Pleistocene nothrotheres are shown to form a clade. It is suggested that this latter clade merits recognition as a distinct family‐level grouping, the family Nothrotheriidae. The monophyly of the Megatherioidea, a clade including members of the families Megatheriidae, Megalonychidae and Nothrotheriidae, is also supported. Within Megatherioidea, the families Nothrotheriidae and Megatheriidae form a monophyletic group called the Megatheria. The relationships within the families Megatheriidae and Mylodontidae are fully and consistently resolved, although the hypothesized scheme of relationships among the late Miocene to Pleistocene members of the mylodontid subfamily Mylodontinae differ strongly from any proposed by previous authors. Within the family Megalonychidae, Choloepus is allied to a monophyletic grouping of West Indian sloths, although the relationships within this clade are not fully resolved. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 140 , 255–305. 相似文献
10.
Phylogenetic relationships within Adiaphanida (phylum Platyhelminthes) and the status of the crustacean‐parasitic genus Genostoma
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The existence of the platyhelminth clade Adiaphanida—an assemblage comprising the well‐studied order Tricladida as well as two lesser known taxa, Prolecithophora and the obligate parasitic Fecampiida—is among the more surprising results of flatworm molecular systematics. Each of these three clades is itself largely well‐defined from a morphological point of view, although Adiaphanida at large, despite its strong support in molecular phylogenetic analyses, lacks known morphological synapomorphies. However, one taxon, the genus Genostoma, a parasite of the leptostracan crustacean Nebalia, rests uneasily within its current classification within the fecampiid family Genostomatidae; ultrastructural investigations on this taxon have uncovered a spermatogenesis reminiscent of Kalyptorhynchia, and a dorsal syncytium resembling the neodermatan tegument. Here, we provide molecular sequence data (nearly complete 18S and 28S rRNA) from a representative of Genostoma, with which we test hypotheses on the phylogenetic position of this taxon within Platyhelminthes, expanding upon a recently published phylum‐wide analysis, and applying novel alignment algorithms and substitution models. These analyses unequivocally position Genostoma as the sister group of Prolecithophora. However, even in taxon‐rich analyses, support for the position of the root of Adiaphanida is lacking, highlighting the need for new data types to study the phylogeny of this clade. Interestingly, our analyses also do not recover the monophyly of several taxa previously proposed, notably Continenticola within Tricladida and Protomonotresidae within Prolecithophora. In light of this phylogeny and the distinctive morphology (especially, spermatogenesis) of Genostoma, we advocate for a redefinition of the family Genostomatidae, outside of both Fecampiida and Prolecithophora, to encompass the members of this unique genus of parasites. Within Fecampiida, the family Piscinquilinidae fam. nov. is erected to accommodate the vertebrate‐parasitic Piscinquilinus, formerly Genostomatidae. 相似文献
11.
Postnatal development of six species of sessile rotifers in the families Flosculariidae (Floscularia decora, Lacinularia flosculosa, Limnias ceratophylli, Ptygura crystallina) and Collothecidae (Collotheca ornata, Stephanoceros fimbriatus) was investigated by observing free-swimming and newly settled larvae until they metamorphosed into adults. Three variants of metamorphosis were observed. A hypothetical explanation of changes of the coronal construction of orders Gnesiotrocha and Pseudotrocha is considered. 相似文献
12.
Suresh P. Benjamin Dimitar Dimitrov Rosemary G. Gillespie Gustavo Hormiga 《Cladistics : the international journal of the Willi Hennig Society》2008,24(5):708-722
The first quantitative phylogenetic analysis of three sequenced genes (16S rRNA, cytochrome c oxidase subunit I, histone 3) of 25 genera of crab spiders and 11 outgroups supports the monophyly of Thomisidae. Four lineages within Thomisidae are recovered. They are informally named here as the Borboropactus clade, Epidius clade, Stephanopis clade and the Thomisus clade, pending detailed morphology based cladistic work. The Thomisus clade is recovered as a strongly supported monophyletic group with a minimal genetic divergence. Philodromidae previously widely considered a subfamily of Thomisidae do not group within thomisids and is excluded from Thomisidae. However, Aphantochilinae previously generally considered as a separate family falls within the Thomisus clade and is included in Thomisidae. The recently proposed new family Borboropactidae is rejected, as it is paraphyletic. © The Willi Hennig Society 2008. 相似文献
13.
A molecular phylogeny of Planorboidea (Gastropoda, Pulmonata): insights from enhanced taxon sampling 总被引:4,自引:0,他引:4
Planorbid gastropods are the most diverse group of limnic pulmonates, with both discoidal and highspired taxa. Phylogenetic relationships among these genera are confused and controversial. In particular, the monophyly of the limpet‐like taxa (traditionally Ancylidae) is disputed. Even recent molecular studies have concluded that substantially more work is necessary to solve the remaining issues concerning intergeneric phylogenetic relationships and higher taxa systematics. Planorbid snails are of great significance for humans as several members of this group are intermediate hosts of blood flukes (schistosomes) causing a chronic disease, schistosomiasis. We used the two independent molecular markers COI and 18S (concatenated dataset of 2837 nucleotide bp) to infer phylogenetic relationships of 26 genera (27 species) of Planorboidea, represented mostly by type species from mainly topotypical populations. With the majority of the taxa discussed not having been studied previously, this study attempted to test several hypotheses on planorbid phylogenetic relationships using Bayesian inference techniques. The monophyly of Planorboidea (= ‘Ancyloplanorbidae’) is strongly suggested on the basis of our extensive molecular analysis. Besides a distinct Burnupia clade, two major clades were recovered that correspond to family level taxa (traditional Bulinidae and Planorbidae). Considerable rearrangements of suprageneric taxa are evident from the phylogeny inferred. Therefore, the only clades recognized by current classifications and supported by our analysis are Planorbini and Segmentinini. The present study found that Ancylidae as traditionally understood, i.e. covering most freshwater limpet gastropods, is paraphyletic, as the genera of Burnupia and Protancylus have been shown to lie phylogenetically outside the Ancylini. Chromosome numbers and levels of polyploidy are discussed in the light of the new phylogeny. An earlier theory of shell shape evolution, i.e. that of patelliform taxa being most advanced, was not supported by this study; a limpet‐shaped taxon is most basal within Planorboidea. Although many taxa still remain to be studied, our results will hopefully contribute towards a better understanding of this very important group of freshwater organisms. Some taxonomic implications are discussed. 相似文献
14.
Phylogeny and morphological evolution of the so‐called bougainvilliids (Hydrozoa,Hydroidolina)
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María A. Mendoza‐Becerril Adrian José Jaimes‐Becerra Allen G. Collins Antonio C. Marques 《Zoologica scripta》2018,47(5):608-622
We present phylogenetic analyses (parsimony, maximum likelihood and Bayesian inference) for 69 lineages of anthoathecate hydroids based on 18 morphological characters (12 proposed for the first time) plus mitochondrial (16S and COI) and nuclear (18S and 28S) molecular markers. This study aims to test the monophyly of the present concept of the family Bougainvilliidae, assessing its phylogenetic position within Hydroidolina. Our working hypothesis is used as a context for inferring the evolution of certain morphological characters, focusing on the exoskeleton. Our results shed light on some phylogenetic uncertainties within Hydroidolina, delimiting eight well‐supported linages, viz. Hydroidolina, Siphonophorae, Leptothecata, Aplanulata, Filifera II, Filifera III, Capitata and Pseudothecata taxon novum, the latter supported by four morphological synapomorphies. The monophyly of several families was not supported, viz. Bougainvilliidae, Cordylophoridae, Oceaniidae, Rathkeidae and Pandeidae. Some of the genera typically considered in Bougainvilliidae, including Bougainvillia, fell into the clade Pseudothecata, which is consistently reconstructed as the sister group of Leptothecata. We formally suggest that Dicoryne be removed from Bougainvilliidae and placed in the resurrected family Dicorynidae. The exoskeleton was a key feature in the diversification of Hydroidolina, especially with the transition from the bare hydranth to one completely enveloped within the exoskeleton. In this context, bougainvilliids exhibit several intermediate states in the development of the exosarc. Although the concatenated analysis unravels some interesting hypotheses, taxon sampling is still deficient and therefore more data are necessary for achieving a more complete understanding of the evolution and ecology of bougainvilliids and their allies. 相似文献
15.
The systematic position of Meruidae (Coleoptera, Adephaga) and the phylogeny of the smaller aquatic adephagan beetle families 总被引:1,自引:0,他引:1
Rolf G. Beutel Michael Balke Warren E. Steiner Jr 《Cladistics : the international journal of the Willi Hennig Society》2006,22(2):102-131
A phylogenetic analysis of Adephaga is presented. It is based on 148 morphological characters of adults and larvae and focussed on a placement of the recently described Meruidae, and the genus‐level phylogeny of the smaller aquatic families Gyrinidae, Haliplidae and Noteridae. We found a sister group relationship between Gyrinidae and the remaining adephagan families, as was found in previous studies using morphology. Haliplidae are either the sister group of Dytiscoidea or the sister group of a clade comprising Geadephaga and the dytiscoid families. Trachypachidae was placed as the sister group of the rhysodid‐carabid clade or of Dytiscoidea. The monophyly of Dytiscoidea including Meru is well supported. Autapomorphies are the extensive metathoracic intercoxal septum, the origin of the metafurca from this structure, the loss of Mm. furcacoxalis anterior and posterior, and possibly the presence of an elongated subcubital setal binding patch. Meruidae was placed as sister group of the Noteridae. Synapomorphies are the absence of the transverse ridge of the metaventrite, the fusion of abdominal segments III and IV, the shape of the strongly asymmetric parameres, and the enlargement of antennomeres 5, 7 and 9. The Meru‐noterid clade is the sister group of the remaining Dytiscoidea. The exact position of Aspidytes within this clade remains ambiguous: it is either the sister group of Amphizoidae or the sister group of a clade comprising this family and Hygrobiidae + Dytiscidae. The sister group relationship between Spanglerogyrinae and Gyrininae was strongly supported. The two included genera of Gyrinini form a clade, and Enhydrini are the sister group of a monophylum comprising the remaining Enhydrini and Orectochilini. A branching pattern (Peltodytes + (Brychius + Haliplus)) within Haliplidae was confirmed. Algophilus, Apteraliplus and the Haliplus‐subgenus Liaphlus form a clade. The generic status of the two former taxa is unjustified. The Phreatodytinae are the sister group of Noterinae, and Notomicrus (+ Speonoterus), Hydrocoptus, and Pronoterus branch off successively within this subfamily. The search for the larvae of Meru and a combined analysis of morphological and molecular data should have high priority. © The Willi Hennig Society 2006. 相似文献
16.
Nuclear‐encoded SSU rDNA, chloroplast LSU rDNA, and rbcL genes were sequenced from 53 strains of conjugating green algae (Zygnematophyceae, Streptophyta) and used to analyze phylogenetic relationships in the traditional order Zygnematales. Analyses of a concatenated data set (5,220 nt) established 12 well‐supported clades in the order; seven of these constituted a superclade, termed “Zygnemataceae.” Together with genera (Zygnema, Mougeotia) traditionally placed in the family Zygnemataceae, the “Zygnemataceae” also included representatives of the genera Cylindrocystis and Mesotaenium, traditionally placed in the family Mesotaeniaceae. A synapomorphic amino acid replacement (codon 192, cysteine replaced by valine) in the LSU of RUBISCO characterized this superclade. The traditional genera Netrium, Cylindrocystis, and Mesotaenium were shown to be para‐ or polyphyletic, highlighting the inadequacy of phenotypic traits used to define these genera. Species of the traditional genus Netrium were resolved as three well‐supported clades each distinct in the number of chloroplasts per cell, their surface morphology (structure and arrangement of lamellae) and the position of the nucleus or nuclear behavior during cell division. Based on molecular phylogenetic analyses and synapomorphic phenotypic traits, the genus Netrium has been revised, and a new genus, Nucleotaenium gen. nov., was established. The genus Planotaenium, also formerly a part of Netrium, was identified as the sister group of the derived Roya/Desmidiales clade and thus occupies a key position in the evolutionary radiation leading to the most species‐rich group of streptophyte green algae. 相似文献
17.
Javier Ortega‐Hernández David A. Legg Simon J. Braddy 《Cladistics : the international journal of the Willi Hennig Society》2013,29(1):15-45
The phylogenetic position of aglaspidids, a problematic group of Lower Palaeozoic arthropods of undetermined affinities, is re‐examined in the context of the major Cambrian and Ordovician lamellipedian arthropod groups. A cladistic analysis of ten genera of aglaspidids sensu stricto, six aglaspidid‐like arthropods and 42 Palaeozoic arthropod taxa indicates that Xenopoda, Cheloniellida, Aglaspidida sensu lato and Trilobitomorpha form a clade (Artiopoda Hou and Bergström, 1997 ) nested within the mandibulate stem‐lineage, thus discarding previous interpretations of these taxa as part 'of the chelicerate stem‐group (Arachnomorpha Heider, 1913 ). The results confirm an aglaspidid identity for several recently described arthropods, including Quasimodaspis brentsae, Tremaglaspis unite, Chlupacaris dubia, Australaglaspis stonyensis and an unnamed Ordovician Chinese arthropod. The problematic Bohemian arthropod Kodymirus vagans was recovered as sister taxon to Beckwithia typa, and both form a small clade that falls outside Aglaspidida sensu stricto, thus discarding eurypterid affinities for the former. The analysis does not support the phylogenetic position of Kwanyinaspis maotianshanensis at the base of Conciliterga as proposed in recent studies, but rather occupies a basal position within Aglaspidida sensu lato. The results indicate a close association of aglaspidid arthropods with xenopods (i.e. Emeraldella and Sidneyia) and cheloniellids (e.g. Cheloniellon, Duslia); the new clade “Vicissicaudata” is proposed to encompass these arthropods, which are characterized by a differentiated posterior region. The phylogenetic position of aglaspidid arthropods makes them good outgroup candidates for analysing the internal relationships within the groups that form Trilobitomorpha. This work provides a much clearer picture of the phylogenetic relationships among Lower Palaeozoic lamellipedians. 相似文献
18.
The fork-tongued frogs, members of the amphibian Order Anura, belong to the family Dicroglossidae and are one of the most diverse groups of Anuran frogs; however, their taxonomy and phylogeny remain controversial. In the present study, sixteen dicroglossine mitochondrial genomes representing nine dicroglossine genera and 23 other neobatrachian taxa, were used to reconstruct the phylogenetic relationships of the family Dicroglossidae using different partitioned maximum likelihood and partitioned Bayesian inference methods at both the nucleotide and amino acid levels. The sampled fork-tongued frogs form a strongly supported monophyletic group that is the sister taxon to another well-supported clade that includes representatives of the families Ranidae, Rhacophoridae, and Mantellidae. The monophyly of the subfamily Occidozyginae and Dicroglossinae was revealed with strong supports, and two major clades were supported within Dicroglossinae. The sister-group relationship between the genera Limnonectes and the tribe Paini was supported. In addition, a sister-group relationships between Fejervarya and Euphlyctis + Hoplobatrachus, between Quasipaa and Yerana, and between Feirana and Nanorana are well supported. Estimates of divergence times revealed the divergence of Dicroglossidae during the Late Upper Cretaceous to the Early Eocene, and diversification of the major dicroglossine genera from the Early Eocene to the Middle Miocene. 相似文献
19.
Nikolas P. Johnston Marcin Piwczyński Paulina Trzeciak Kinga Walczak Krzysztof Szpila 《Systematic Entomology》2023,48(2):296-315
The Polleniidae (Diptera) are a family of flies best known for species of the genus Pollenia, which overwinter inside human dwellings. Previously divided across the Calliphoridae, Tachinidae and Rhinophoridae, the polleniid genera have only recently been united. Several studies have utilized molecular data to analyse polleniid phylogenetic relationships, although all have suffered from low taxon sampling or insufficient phylogenetic signal in molecular markers. To alleviate these problems, we utilized two automated organellar genome extraction software, GetOrganelle and MitoFinder, to assemble mitogenomes from genome skimming data from 22 representatives of the polleniid genera: Dexopollenia, Melanodexia, Morinia, Pollenia and Xanthotryxus. From these analyses, we provide 14 new mitogenomes for the Polleniidae and perform phylogenetic analyses of 13 protein-coding mitochondrial genes using both maximum likelihood and Bayesian inference. Subfamilial phylogenetic relationships within the Polleniidae are interrogated and Pollenia is found to form a monophyletic clade sister to Melanodexia, Morinia and Dexopollenia, providing no evidence for the synonymisation of any of these genera. Our topology conflicts with previous morphology-based cladistic interpretations, with the amentaria, griseotomentosa, semicinerea and viatica species-groups resolving as non-monophyletic. We provide support for our topology through analysis of adult morphology and male and female terminalia, while identifying new diagnostic characters for some of the clades of the Pollenia. To test the validity of the current diagnostic morphology in the Polleniidae, newly assembled cytochrome C oxidase subunit 1 (COI) data are combined with a polleniid COI barcode reference library and analysed using the species delimitation software ASAP. COI barcodes support the current morphologically defined species within the Pollenia. 相似文献
20.
A reassessment of Eocene parrotlike fossils indicates a previously undetected radiation of zygodactyl stem group representatives of passerines (Passeriformes)
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Gerald Mayr 《Zoologica scripta》2015,44(6):587-602
In the past years, various Eocene fossil birds were described as stem group representatives of the zygodactyl Psittaciformes (parrots). These birds show quite disparate morphologies, which cast some doubt on the correct assignment of all of them to the psittaciform stem group. A reassessment of their affinities is further needed, because it was recently proposed that among extant birds, Psittaciformes and Passeriformes (passerines) form a clade and that passerines possibly derived from a zygodactyl ancestor. Here, phylogenetic analyses are performed, which for the first time also include representatives of the Zygodactylidae, the extinct zygodactyl sister taxon of the Passeriformes. The early Eocene Psittacopes was originally described as a stem group representative of Psittaciformes. However, none of the present analyses supported psittaciform affinities for Psittacopes and instead recovered this taxon in a clade together with zygodactylids and passerines. Also part of this clade are the early Eocene taxa Pumiliornis and Morsoravis, and it is detailed that Psittacopes and the long‐beaked and presumably nectarivorous Pumiliornis, with which it has not yet been compared, are very similar in their postcranial osteology. The present analysis corroborates the hypothesis of a zygodactyl stem species of passerines. To account for these results, Psittacopes is here assigned to a new higher‐level taxon and a new name is also introduced for the clade including Zygodactylidae and Passeriformes. 相似文献