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1.
The freshwater African catfish family Amphiliidae had been reviewed based on the 73 osteological characters with Diplomystidae, 2 Hypsidoridae, Amblycipitidae, Sisoridae, and Bagridae as out-groups. Because the family position of Leptoglanis (Bagridae/Amphiliidae) is under debate, this genus has been taken as an out-group too. Results of the study indicate that: 1) the Amphiliidae is not a monophyletic group and must now be restricted to the genera Amphilius and Paramphilius; the two subfamilies Amphiliinae and Doumeinae are separated by the sisorids Euchiloglanis (with most of the glyptosternid fishes) and Glyptothorax (with most of the non-glyptosternid fishes); 2) no synapomorphies were found for the subfamily Amphiliinae. 3) The five genera of subfamily Doumeinae constitute a monophyletic group, Andersonia being the sister-group of the four other genera; subfamily Doumeinae + Leptoglanis form the family Doumeidae. The glyptosternids no longer belong to the Sisoridae (family restricted to the non-glyptosternids) and represent the new family Glyptosternidae.  相似文献   

2.
The monophyly of the ichneumonid clade Pimpliformes is established and the phylogenetic relationships of the eight component subfamilies are resolved. The clade (Acaenitinae + (Diacritinae + (Cylloceriinae + (Diplazontinae + Orthocentrinae)))) is the sister-lineage to the clade (Pimplinae + (Rhyssinae + Poemeniinae)). The Nearctic genus Cressonia Dasch is transferred to the Diacritinae from the Orthocentrinae. Tribes are not recognized in the Acaenitinae as the Coleocentrini (sensu Townes, 1971) is paraphyletic with respect to the Acaenitini. The Cylloceriinae is recognized as comprising three genera, Cylloceria Schiødte, Allomacrus Förster and Sweaterella gen.n. The Orthocentrinae, including the Helictinae of authors, is shown to be monophyletic, but the latter is clearly shown to be paraphyletic if the Orthocentrus genus-group is excluded. The Pimplinae comprises four monophyletic tribes: the Delomeristini, consisting of Delomerista Förster and Atractogaster Kriechbaumer; the Perithoini trib.n., which includes only Perithous Holmgren (= Hybomischos Baltazar syn.n.); the Pimplini, which includes the Theronia genus-group as well as the Pimpla genus-group; and the Ephialtini, which includes the Polysphinctini syn.n., a monophyletic group that previously rendered the restricted Ephialtini paraphyletic. The tribe Delomeristini is the sister-group to the clade (Ephialtini + (Perithoini + Pimplini)). The subfamily Poemeniinae is recognized as comprising three tribes: the Pseudorhyssini (trib.n.) which includes the single Holarctic genus Pseudorhyssa Merrill; the Rodrigamini (trib.n.) which includes only the Costa Rican genus Rodrigama Gauld; and the Poemeniini. The tribe Pseudorhyssini is the sister-group to the clade (Rodrigamini + Poemeniini). The phylogenetic inter-relationships of the genera of Poemeniini are resolved. A new genus from South Africa, Guptella (gen.n.) is described, and Achorocephalus Kriechbaumer is shown to be a synonym of Eugalta Cameron (syn.n.). The evolution of biological traits within the Pimpliformes is discussed with reference to the elucidated phylogeny, and zoogeographic patterns are outlined.  相似文献   

3.
The 27 species of the aquatic frog family Pipidae are currently arranged in four genera: Xenopus (15 species), Hymenochirus (four species), and the poorly known genus Pseudhymenochirus (one species) occur in Africa; Pipa (seven species) is found in South America and lower Central America. Despite extensive work on the biology of Xenopus from various disciplines, the evolutionary relationships of Xenopus to other pipids have not been resolved. Phylogenetic analyis of morphological features of pipid frogs indicates that, contrary to earlier opinions, Hymenochirus and Pipa are closest relatives (sister-groups); these genera are placed in the subfamily Pipinae. Also, the currently recognized species of Xenopus do not form a natural group; the species tropicalis and epitropicalis are more closely related to Hymenochirus + Pipa than to the remaining species of Xenopus . The two discordant species are transferred to the genus Silurana , which is relegated to the new subfamily Siluraninae; it is the sister-group of the Pipinae. The remaining species of Xenopus constitute a monophyletic group that is placed in the subfamily Xenopodinae as the sister-group of the other genera of pipids.  相似文献   

4.
The Ichthyosauria is the group of Mesozoic marine reptiles that was most highly adapted to the aquatic environment. The first ichthyosaurs from the upper Lower Triassic (Spathian) already show a suite of unique characters (very large eyes, elongate snout, deeply amphicoelous vertebrae, limb modified to fins) correlated with a fully aquatic existence and probably were unable to leave the water. The key evolutionary innovation was vivipary, giving birth to live young, which is documented by the fossil record since the end of the Anisian. Major evolutionary trends in the locomotor apparatus are the increasing modification of the fin skeleton to a mosaic of bones and the change from anguiliform swimming in the earliest forms to thunniform swimming in the Jurassic and later forms, as evidenced by the shortening of the body and the evolution of a semilunate tail fin. Almost from the beginning, ichthyosaurs had a cosmopolitan distribution which was retained until their extinction in the Cenomanian. Ichthyosaurian diversity is greatest in the Middle Triassic with piscivorous, heterodont, and durophagous forms. Jurassic diversity is greatest in the Liassic, declining to one genus (Platypterygius) in the Cretaceous. Although skull characters indicate that ichthyosaurs were diapsids, their exact position within Diapsida is unclear. A cladistic analysis of the well known genera clarifies relationships within the Ichthyosauria. Most basal areGrippia andUtatsusaurus, followed by the Mixosauridae (Mixosaurus andPhalarodon). The Shastasauridae (Cymbospondylus, Shonisaurus, Besanosaurus) are the most advanced Triassic forms and represent the sistergroup of all post-Triassic ichthyosaurs. These are clearly monophyletic and are termed here the Neoichthyosauria.  相似文献   

5.
Male and female imagines of Buchonomyia burmanica sp.n. are described. While the male imago nearly exclusively shows plesiomorphous features, the female imago possesses three important underlying synapomorphies as unique inside-parallelisms: the capacities for divisions of gonapophysis VIII and of tergite IX and for the development of an apodeme lobe. These and supporting evidence lead to the conclusion that Buchonomyia Fittkau deserves a new subfamily, the Buchonomyiinae, which forms the sister-group of the monophyletic unit Chironominae-t-Orthocladiinae+Prodiamesinae+Diamesinae.  相似文献   

6.
The family Cobitidae represents a characteristic element of the Eurasian ichthyofauna. Despite diverse features of sexual dimorphism, comparably few morphological characters have been utilized for taxonomic studies resulting in many unresolved puzzles. Here we present the phylogenetic relationships of Cobitidae as inferred from the mitochondrial cytochrome b gene and the nuclear gene RAG-1. Analyses of both markers show a group of eight nominal genera, which all occur in Europe and eastern, northern and western Asia, forming a monophyletic lineage (northern clade) while all other clades inhabit South and Southeast Asia (southern lineages). While all eight southern lineages correspond to genera as defined by morphological studies, only four lineages were reliably recovered within the northern clade, and of these only one (Sabanejewia) corresponds to a formerly considered genus. The genera Cobitis, Iksookimia and Niwa?lla were polyphyletic. A comparison of the two markers shows several incongruities within the northern clade and mitochondrial introgression at least in the genus Misgurnus. Mapping the characters of sexual dimorphism on our cladogram, we identified five character states that are diagnostic for certain lineages. Estimations of the divergence times dated the separation of the northern clade from the southern lineages to the middle Eocene (46 MYA) and the origin of "Cobitis"misgurnoides, the basal taxon of the northern clade, during early Oligocene (30-35 MYA). The geographic distribution of the major clades supports recently developed hypotheses about the river history of East Asia and further suggests that a range expansion of the northern clade in late Miocene (15 MYA) led to the colonisation of Europe by three already distinct genera.  相似文献   

7.
This paper represents the first cladistic analysis of the interrelationships of all nominal fossil and living gonorynchiform genera. Gonorynchiformes is the basal group of the superorder Ostariophysi, and is confirmed as monophyletic on the basis of 12 synapomorphies. The Gonorynchiformes is be subdivided into two monophyletic suborders, Chanoidei and Gonorynchoidei. The Chanoidei includes the family Chanidae, which in turn includes the Recent Chanos plus five fossil genera, grouped in two subfamilies: Chaninae (( Chanos +† Tharrhiai) + † Parachanos +† Dastilbe ) and † Rubiesichthyinae († Rubiesichthys +† Gordichthys ). † Aethalionopsis is the sister-group to the Chanidae. Gonorynchoidei includes two families Gonorynchidae and Kneriidae. Gonorynchidae is formed by ( Gonorynchus, † Notogoneus ) and four fossil taxa of uncertain definition and interrelationships: †Charitosomus, † Charitopsis, † Ramallichthys, and †fudeichthys. The last four genera were previously included in the families †Charitosomidae and †Judeichthyidae, which could not be supported as monophyletic in this analysis. Kneriidae consists of two subfamilies Phractolaeminae with one genus Phractolaemus, and Kneriinae which includes (( Kneria + Parakneria ) + ( Grasseichthys + Cromeria )), the latter two being paedomorphic forms. The Phractolaeminae and the Kneriinae are freshwater African taxa with no known fossil record. The order Gonorynchiformes is represented herein by 18 genera, extending back to the Early Cretaceous. More work is required to clarify the interrelationships of the Gonorynchidae and the paedomorphic characters that apparently played an important role in the evolution of this morphologically diverse group of fishes.  相似文献   

8.
《Palaeoworld》2014,23(3-4):263-275
A fundamental aspect of taxonomy at the generic level, critical to understand Early Triassic conodont evolution, is the composition of the multielement apparatus. In this paper, we document a platform-bearing new conodont genus, Parafurnishius n. gen., as well as its multielement apparatus from the Griesbachian Feixianguan Formation (Lower Triassic) in Xuanhan County, northeastern Sichuan Province, southwest China. The new conodont genus is characterized by numerous robust and irregularly distributed conical denticles with variable platform morphology that has a possible affinity with the P1 elements of Furnishius. These genera have apparatuses similar to those of Ellisonia and are classified with the family Ellisoniidae. The strong intraspecific variation of P1 elements and the growth series within the entire sample population suggest that Parafurnishius may have evolved from the Griesbachian Isarcicella by developing random denticle positioning away from the platform centre, and then possibly evolved into younger Triassic Furnishius by developing a stable blade configuration. This preferred interpretation implies an ellisonid apparatus for Isarcicella. Alternatively, Parafurnishius may have evolved from Ellisonia and developed a homeomorphic P1 element with Isarcicella. This new taxon has strong intraspecific variation of denticle growth orientation during the Early Triassic.  相似文献   

9.
10.
A new genus,Siemensichthys, from the Upper Jurassic of southern Germany is described. The new genus includes two species,S. macrocephalus (Agassiz) which was formerly in the genusPholidophorus, andS. siemensi n. sp. The two species share synapomorphies such as only one supramaxillary bone covering the dorsal margin of the maxilla. Both species are described, and their phylogenetic position is analyzed. The phylogenetic analyses, based on 27 taxa and 141 characters, show thatAnkylophorus from the Kimmeridgian of Cerin,Siemensichthys andEurycormus from the Solnhofen Lithographic Limestone of Bavaria, form a monophyletic group. The new extinct clade (preliminarily identified as theSiemensichthys- group) is proposed as the sister-group ofPholidophorus s. str. plus more advanced teleosts. This sister-group relationship is supported by eight characters (e.g., supraoccipital bone extending forward in the roof of the otic region; articular bone fused with both the angular and retroarticular; presence of an elongated posteroventral process of quadrate; presence of dorsal processes at the base of the innermost caudal rays of upper lobe; mobile premaxillary bone). Comparisons with species ofPholidophorus s. str. provide a new understanding of the genusPholidophorus. At least four synapomorphies are proposed to support the monophyly ofPholidophorus. As a consequence of this new interpretation, the European Late Jurassic species previously assigned to the Pholidophoridae and to the genusPholidophorus (e.g., ‘Ph.’armatus, ‘Ph.’ falcifer, ‘Ph.’ micronyx, ‘Ph.’ microps) should be reexamined because they do not belong to the family nor to the genus. The order PholidophoriformesBerg is not a monophyletic group as currently constructed. Therefore, all so-called pholidophoriforms are in need of revision.  相似文献   

11.
Abstract:A phylogenetic hypothesis based on nuclear ITS sequence data is presented for the familyPhysciaceae , based on various representatives of foliose and fruticose groups and a number of species selected from the crustose genera Rinodina and Buellia s.l. The analysis supports the monophyly of the Physcia - and theBuellia -groups. This is in agreement with existing morphological evidence, particularly ascus characters. ThePhyscia group in the analysis includes the genera Anaptychia, Heterodermia, Hyperphyscia,Mobergia , Phaeophyscia, Phaeorrhiza, Physcia, Physconia, Rinodina, andRinodinella , while the Buellia group includes Amandinea, Buellia and Diploicia. The genera Physcia, Phaeophyscia, Phaeorrhiza and Rinodinella were well supported as monophyletic groups. The support for Physconia is low. Rinodina and Buellia are not supported as monophyletic genera. In agreement with ascus and ascospore characters, Buellia lindingeri is placed within the Rinodina group, close to R. lecanorina. The genus Amandinea as currently circumscribed was not supported as a monophyletic group. The analysis confirms results from other lichen families that foliose members have evolved more than once from crustose lichens.Rinodina and Rinodinella species without chemical compounds in their thalli form the sister group toPhaeophyscia , and both groups form a monophyletic assemblage. A more detailed analysis of the Physcia group is presented. Whilst several of the foliose genera were well supported, there is only poor support for traditionally accepted crustose genera. The taxonomic implications of these findings are discussed.  相似文献   

12.
The most striking feature of peafowl (Pavo) is the males'' elaborate train, which exhibits ocelli (ornamental eyespots) that are under sexual selection. Two additional genera within the Phasianidae (Polyplectron and Argusianus) exhibit ocelli, but the appearance and location of these ornamental eyespots exhibit substantial variation among these genera, raising the question of whether ocelli are homologous. Within Polyplectron, ocelli are ancestral, suggesting ocelli may have evolved even earlier, prior to the divergence among genera. However, it remains unclear whether Pavo, Polyplectron and Argusianus form a monophyletic clade in which ocelli evolved once. We estimated the phylogeny of the ocellated species using sequences from 1966 ultraconserved elements (UCEs) and three mitochondrial regions. The three ocellated genera did form a strongly supported clade, but each ocellated genus was sister to at least one genus without ocelli. Indeed, Polyplectron and Galloperdix, a genus not previously suggested to be related to any ocellated taxon, were sister genera. The close relationship between taxa with and without ocelli suggests multiple gains or losses. Independent gains, possibly reflecting a pre-existing bias for eye-like structures among females and/or the existence of a simple mutational pathway for the origin of ocelli, appears to be the most likely explanation.  相似文献   

13.
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   

14.
The rove beetle tribe Amblyopinini (Coleoptera: Staphylinidae: Staphylininae) is a recently discovered monophyletic lineage comprising an estimated 1000 or more species of mainly leaf- and log litter-dwelling predatory insects found throughout the southern hemisphere. Of these, a single genus Heterothops Stephens somehow conquered all continents in the northern hemisphere as well. A few lineages of amblyopinines independently evolved into highly derived predators of mammal ectoparasites from free-living ancestors. In return, they are tolerated in the mammal fur and nests, which is a unique example of cleaning symbiosis between insects and vertebrates. For over a century the great majority of free-living southern amblyopinines were incorrectly placed in the northern hemisphere-restricted, and superficially similar, rove beetle genera from the subtribe Quediina. Only their mammal-associated derived forms were understood as amblyopinines, a nonmonophyletic taxon of volatile status and enigmatic sister-group relationships of its various members. Here we present the first comprehensive phylogeny of Amblyopinini inferred with Bayesian analysis of a six-gene molecular dataset (4672 bp) across a broad sample of taxa (90 species). This phylogeny provides a framework for the badly needed taxonomic inventory of this group and, in particular, reveals at least two independent origins of mammal association within the tribe. It frames the upcoming in-depth interdisciplinary exploration of a variety of phenomena such as evolution of the austral biota in response to continental drift and climate change, biotic exchange between southern and northern continents, origin and evolution of beetle–mammal symbiosis, and pathways and constraints of the evolutionary parallelisms.  相似文献   

15.
A new genus and species of the Meropeidae (Mecoptera, Insecta) from the Middle Jurassic of Siberia (Russia) is described:Boreomerope antiqua gen. et sp. nov. It is the first known fossil of the family, and it shows some plesiomorphic characters as compared to the Recent meropeids. The systematic position ofBoreomerope is discussed.  相似文献   

16.
The relationships of Nesomyinae, a group of murid rodents endemic to the island of Madagascar, were investigated with two comparative molecular approaches. Compared to those of other muroid rodents representing Murinae, Cricetinae, Cricetomyinae. Arvicolinae, and Sigmodontinae, complete sequences of the 12S rRNA mitochondrial gene suggest that the Malagasy nesomyinesMacrotarsomys andNesomys are monophyletic and that their sister-group among the taxa analyzed isCricetomys. A limited series of DNA/DNA hybridization experiments extends these observations to a third nesomyine genus,Eliurus, and a second cricetomyine taxon,Saccostomus. By relating the amounts of overall genomic divergence with geological time as calibrated by theMus/Rattus dichotomy estimated at 12–14 My, the oldest within-Nesomyinae dichotomy is estimated to be 10.8 to 12.6 My. Thus, these three genera of Malagasy nesomyine rodents appear to be a rather ancient offshoot from African ancestors whose Recent relatives are Cricetomyinae. This preliminary observation should be confirmed by sampling additional genera of nesomyines and additional representatives for other subfamilies of African muroids.  相似文献   

17.
The genus Streptomyces comprises a group of bacteria species with high economic importance. Several of these species are employed at industrial scale for the production of useful compounds. Other characteristic found in different strains within this genus is their capability to tolerate high level of substances toxic for humans, heavy metals among them. Although several studies have been conducted in different species of the genus in order to disentangle the mechanisms associated to heavy metal resistance, little is known about how they have evolved along Streptomyces phylogeny. In this study we built the largest Streptomyces phylogeny generated up to date comprising six genes, 113 species of Streptomyces and 27 outgroups. The parsimony-based phylogenetic analysis indicated that (i) Streptomyces is monophyletic and (ii) it appears as sister clade of a group formed by Kitasatospora and Streptacidiphilus species, both genera also monophyletic. Streptomyces strains resistant to heavy metals are not confined to a single lineage but widespread along Streptomyces phylogeny. Our result in combination with genomic, physiological and biochemical data suggest that the resistance to heavy metals originated several times and by different mechanisms in Streptomyces history.  相似文献   

18.
The phylogenetic system of the Mecoptera   总被引:9,自引:0,他引:9  
Abstract. Many families like the Mesochoristidae, Agetopanorpidae and Permopanorpidae, which were believed by earlier writers to be Mecoptera, are members of the stem group of the Antliophora (Diptera Mecoptera+Siphonaptera) or of stem groups of monophyletic groups of even higher rank (e.g. Mecopteroidea). Others - like the so-called 'Pro-tomecoptera' from the Permian of the Kusnetsk Basin - are not even closely related to the Mecopteroidea. Only the families mentioned in the following phylogenetic system of the Mecoptera are definitely members of the order:
1 Nannomecoptera (Nannochoristidae)
2 Pistillifera
2.1 Raptipedia (Neorthophlebiidae, Bittacidae, Cimbrophlebiidae)
2.2 Opisthogonopora
2.2.1 Boreomorpha (Boreidae)
2.2.2 Meropomorpha (Meropeidae)
2.2.3 Panorpomorpha
2.2.3.1 Eomeropina (Eomeropidae=Notiothaumidae)
2.2.3.2 Panorpina
2.2.3.2.1 Apteropanorpini (Apteropanorpidae)
2.2.3.2.2 Panorpini
2.2.3.2.2.1 Choristoidea (Choristidae)
2.2.3.2.2.2 Panorpoidea (Orthophlebiidae, Dinopanorpidae, Austropan-orpidae, Muchoriidae, Panorpodidae, Panorpidae)
The Orthophlebiidae and Neorthophlebiidae are not monophyletic. There are, however, no characters preserved which would allow a clarification of the exact relations between members of these two groups and the families derived from them. The fossil Xenochoristidae, Triasso-choristidae, Mesopanorpodidae and Robinjohniidae may be further members of the Mecoptera. Their exact phylogenetic relations, however, are unknown.  相似文献   

19.
Paul C. Sereno 《ZooKeys》2012,(226):1-225
Heterodontosaurids comprise an important early radiation of small-bodied herbivores that persisted for approximately 100 My from Late Triassic to Early Cretaceous time. Review of available fossils unequivocally establishes Echinodon as a very small-bodied, late-surviving northern heterodontosaurid similar to the other northern genera Fruitadens and Tianyulong. Tianyulong from northern China has unusual skeletal proportions, including a relatively large skull, short forelimb, and long manual digit II. The southern African heterodontosaurid genus Lycorhinus is established as valid, and a new taxon from the same formation is named Pegomastax africanus gen. n., sp. n. Tooth replacement and tooth-to-tooth wear is more common than previously thought among heterodontosaurids, and in Heterodontosaurus the angle of tooth-to-tooth shear is shown to increase markedly during maturation. Long-axis rotation of the lower jaw during occlusion is identified here as the most likely functional mechanism underlying marked tooth wear in mature specimens of Heterodontosaurus. Extensive tooth wear and other evidence suggests that all heterodontosaurids were predominantly or exclusively herbivores. Basal genera such as Echinodon, Fruitadens and Tianyulong with primitive, subtriangular crowns currently are known only from northern landmasses. All other genera except the enigmatic Pisanosaurus have deeper crown proportions and currently are known only from southern landmasses.  相似文献   

20.
Asteropeia andPhysena are both enigmatic woody dicotyledons from Madagascar. Various taxonomic affinities have been suggested for both genera, but no consensus has been reached. An analysis of rbcL sequence data strongly supports recognition of the sister-group relationship ofAsteropeia andPhysena and their placement as the sister group to Caryophyllales. Many similarities were noted betweenAsteropeia andPhysena for stem, wood, leaf, flower, pollen, and fruit characters. The most notable differences are found in the morphology of the flowers and the anatomy of the wood rays.  相似文献   

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