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1.
The phylogeny of the Giant Pill-Millipedes, order Sphaerotheriida, is investigated using a new morphological character matrix comprising 89 characters. The majority of these characters are employed for the first time in millipedes. All trees obtained agree on the monophyletic status of the Sphaerotheriida and several of its tribes, each restricted to a modern land mass. The species from Madagascar displaying island gigantism do not form a monophyletic group. The classic division of Giant Pill-Millipedes into two families, Sphaerotheriidae and Zephronidae, was not reflected in the analysis. The genus Procyliosoma is the sister-group to all other Sphaerotheriida, rendering the family Sphaerotheriidae paraphyletic. A new family-level classification of Giant Pill-Millipedes, based on the current phylogeny, is introduced. The new family Procyliosomatidae contains only the genus Procyliosoma , distributed in Australia and New Zealand. The family Zephronidae remains unchanged, while the family Sphaerotheriidae now incorporates only the African Giant Pill-Millipede genera. All genera from southern India and Madagascar form a monophyletic group and are placed in the new family Arthrosphaeridae. The Malagasy genus Sphaeromimus is more closely related to the Indian Arthrosphaera species than to other genera from Madagascar. A biogeographical analysis identifies the group as a Gondwana taxon (with a notable absence from South America). The current phylogeny of Giant Pill-Millipede families mirrors perfectly the suggested break-up of Gondwana fragments 160–90 Ma. No evidence for a dispersal event could be found, highlighting the importance of Giant Pill-Millipedes as a potential model taxon.  相似文献   

2.
The phylogenetic relationships of the caryophyllidia-bearing dorids are studied, based on the examination of the type species of all the genera previously described. The phylogenetic hypothesis supports that the caryophyllidia-bearing dorids are a monophyletic group and the sister group of the clade formed by Astemnotus Ehrenberg, 1831 and Halgerda Bergh, 1880. Several genera previously considered as valid or regarded as uncertain are here synonymized: Peronodoris Bergh, 1904, Trippa Bergh, 1877, Phlegmodoris Bergh, 1878, Petelodoris Bergh, 1881, Kentrodoris Bergh, 1876, Audura Bergh, 1878, Centrodoris P. Fischer, 1883, Anisodoris Bergh, 1898, Awuka Er. Marcus, 1955, Rhabdochiia P. Fischer, 1883, Boreodoris Odhner, 1939, Dictyodoris Bergh, 1880, Gravieria Vayssiere, 1912, Aporodoris Ihering, 1886. The following genera are regarded as valid: Astemnotus, Atagema J.E. Gray, 1850, Jorunna Bergh, 1876, Platydoris Bergh, 1877, Diaulula Bergh, 1878, Rostanga Bergh, 1879, Halgerda Bergh, 1880, Baptodoris Bergh, 1884, Gargamella Bergh, 1894, Alloiodoris Bergh, 1904, Sclerodoris Eliot, 1904, Taringa Er. Marcus, 1955, Thorybopus Bouchet, 1977. The new genus Nophodoris is described based on two new species from New Caledonia deep waters. Two additional new species from New Caledonia belonging to the genera Atagema and Gargamella are also described. Nomenclatural and taxonomic problems are discussed, and several type species, neotypes and lectotypes are selected.  相似文献   

3.
This paper proposes a refined hypothesis of evolution for the tropical Indo-Pacific nudibranch genus Halgerda . Numerous specimens from 31 species were examined anatomically and literature from four additional species was reviewed, bringing to 33 the ingroup taxa. Fifty-three characters were considered from these examinations. The outgroup Asteronotus was used to polarize the characters. The phylogeny obtained from the analysis of the characters supports the hypothesis that Halgerda is a monophyletic group. A species previously placed with the genus Sclerodoris is examined and determined to be a member of the genus Halgerda . Phylogenetic analysis places this species, H. paliensis , as a basal member of the genus . Halgerda paliensis appears to be restricted to the Hawaiian Islands. Specimens previously identified as Sclerodoris paliensis from the Marshall Islands actually represent H. dalanghita Fahey & Gosliner, 1999. A new species, Halgerda onna , is described and presented as the sister taxon to a basal member of the genus. A range and depth extension of a previously described species, H. malesso , is presented. The present phylogeny is then compared to previous studies, in particular those of Fahey & Gosliner (1999a,b) .  相似文献   

4.
The genus Peperomia is one of the largest genera of basal angiosperms, comprising about 1500-1700 pantropically distributed species. The currently accepted infrageneric classification divides Peperomia into nine subgenera and seven sections. This classification is based on some 200 species, primarily using fruit morphology. The monophyly of these infrageneric taxa has never been tested and molecular phylogenetic studies of a representative sampling within Peperomia do not exist. This paper provides the first molecular phylogeny for the genus Peperomia. Monophyletic clades within Peperomia are identified and previously used morphological characters are critically reviewed. We show that the importance of some morphological characters has been overestimated and that some of these characters presumably have evolved several times independently. Only one previously described subgenus has been confirmed to be monophyletic.  相似文献   

5.
Sundberg, P., Gibson, R. & Olsson, U. (2003). Phylogenetic analysis of a group of palaeonemerteans (Nemertea) including two new species from Queensland and the Great Barrier Reef, Australia. — Zoologica Scripta, 32, 279–296.
Based on 18S rDNA nucleotide sequences and morphological characters, we reconstruct the phylogeny for a group of palaeonemerteans estimated to be monophyletic. Two new palaeonemertean species from Queensland and the Great Barrier Reef, Australia are included in the phylogenetic analysis. The results confirm that one of the species, Cephalothrix queenslandica sp. n., is part of the Cephalothrix–Cephalotrichella–Procephalothrix group. These genera are redefined phylogenetically under the name Cephalothrix based on the cladistic analysis. The other species, Balionemertes australiensis gen. et sp. n., is placed in a new genus which forms a sister taxon to Cephalothrix . The morphology of both new species is described in detail.  相似文献   

6.
Chaverri P  Bischoff JF  Evans HC  Hodge KT 《Mycologia》2005,97(6):1225-1237
A new genus, Regiocrella, is described with two species, R. camerunensis and R. sinensis, based on specimens collected in Cameroon and China. Both species are parasitic on scale insects (Coccidae, Homoptera). Morphological and molecular evidence place the new genus in the Clavicipitaceae (Hypocreales), despite its combination of characters that are atypical of that family; Regiocrella is characterized by having perithecia partly immersed in a subiculum, noncapitate asci, unicellular fusiform ascospores and pycnidial-acervular conidiomata. The two new species, R. camerunensis and R. sinensis, are distinguished based on ascospore and perithecium size. Morphological characters were evaluated and compared to other genera in the Clavicipitaceae, especially those parasitic on scale insects or with pycnidial-acervular anamorphs or synanamorphs (i.e. Aschersonia, Ephelis or Sphacelia): Atkinsonella, Balansia, Claviceps, Epichl?e, Hypocrella, Myriogenospora and Neoclaviceps. The phylogenetic relationships of Regiocrella were examined with three gene loci: large subunit nuclear ribosomal DNA (LSU), translation elongation factor 1-alpha (TEF), and RNA polymerase II subunit 1 (RPB1). The results of this study confirm that Regiocrella is distinct from other genera in the Clavicipitaceae and that its two species form a monophyletic group. Regiocrella is shown to be closely related to the scale insect pathogen Hypocrella and the plant-associated genera Balansia, Claviceps, Epichl?e, Myriogenospora and Neoclaviceps. This study also provides insights into the evolution of pycnidial-acervular conidiomata and scale insect parasitism within the Clavicipitaceae. Plant-associated genera form a monophyletic group correlated with Clavicipitaceae subfamily Clavicipitoideae sensu Diehl. We also demonstrate that scale insect parasites have multiple evolutionary origins within the family and genera with pycnidial-acervular anamorphs or synanamorphs have a single origin.  相似文献   

7.
Mey W 《ZooKeys》2011,(130):331-342
This paper describes a rare case of a male moth in Baltic amber in an excellent position for establishing a species. The moth represents the second species of the genus Baltimartyria Skalski, 1995, described herein as Baltimartyria rasnitsynisp. n. The detection of this new species prompts research on the systematic position of the genus within the family Micropterigidae. The genus was found to provide none of the apomorphic characters that would allow placement in one of the monophyletic lineages within the family. The genus is provisionally assigned to the "southern sabatincoid group", a weakly supported assemblage of Southern Hemisphere genera. The sister genus has still to be determined. Baltimartyria is the first North Hemisphere representative in this group. Some general aspects of historical biogeography relevant for the group are briefly discussed.  相似文献   

8.
Panicum L. is a cosmopolitan genus with approximately 450 species. Although the genus has been considerably reduced in species number with the segregation of many taxa to independent genera in the last two centuries, Panicum remains a heterogeneous assemblage, as has been demonstrated in recent years. The genus is remarkably uniform in its floral characters but exhibits considerable variation in anatomical, physiological, and cytological features. As a result, several classifications, and criteria of what the genus should really include, have been postulated in modern literature. The purpose of this research, based on molecular data of the chloroplast ndhF gene, is to test the monophyly of Panicum, to evaluate infrageneric classifications, and to propose a robust phylogenetic hypothesis. Based on the present results, previous morphological and molecular phylogenetic studies, and inferred diagnostic morphological characters, we restrict Panicum sensu stricto (s.s.) to the former subgenus Panicum and support recognition of Dichanthelium, Phanopyrum, and Steinchisma as distinct genera. We have transfered other species of Panicum to other genera of the Paniceae. Most of the necessary combinations have been made previously, so few nomenclatural changes have been required. The remaining species of Panicum sensu lato (s.l.) are included within Panicum incertae sedis representing isolated species or species grouped within monophyletic clades. Additionally, we explore the performance of the three codon position characters in producing the supported phylogeny.  相似文献   

9.
10.
A molecular phylogenetic study of eastern North American Coreopsis and representatives of other genera of tribe Coreopsideae was conducted using combined sequences from nuclear ITS and two plastid regions (matK, rpl16). A total of 25-30 species has been recognized in five sections of Coreopsis in eastern North America. Based on morphological characters, these taxa have generally been considered a monophyletic group. Our well-resolved phylogeny supports the monophyly of sections that have been recognized in Coreopsis, but the sections collectively do not comprise a monophyletic group because species of north temperate Bidens occur within one of the two major Coreopsis clades. The most notable departure of present results from prior views of relationships among sections is the lack of a sister group relationship between sections Calliopsis and Eublepharis; the shared presence of four-lobed disk floret corollas had been used to support a close relationship between these two sections. Relationships within sections show both similarities and differences with the results of previous studies based primarily on morphological characters. Mapping of morphological characters used taxonomically in Coreopsis and related genera onto the phylogeny indicates that the evolution of these characters has been complex, and this compromises their value for defining monophyletic groups. Examples include the annual habit, alternate leaves, winged fruits, red or brown basal spots on the yellow ligules, and four-lobed disk floret corollas.  相似文献   

11.
Shrimps of the genus Palaemon Weber, 1795 comprise of 86 species with a wide morphological and ecological variability along the tropical and temperate regions. Studies based on molecular data have indicated that despite a recent taxonomic rearrangement, it may remain not monophyletic. On the other hand, cladistic, morphological analyses have suggested the presence of synapomorphies, implying a natural status for the genus. In this work, a broad taxonomic and molecular sampling is applied to verify whether Palaemon is a monophyletic taxon and, based on the recovered phylogeny, identify geographical and morphological patterns related to the lineages. Partial sequences of 16S rRNA, histone H3 and 18S rRNA from 60 species of Palaemon and 15 species from other genera of Palaemonidae were analysed. In addition, previously used characters as well as novel diagnostic characters were scrutinized. The present phylogeny indicates that the species of Palaemon fall into three distinct lineages and that the colonization of America and Europe likely occurred multiple times. Morphological characters allow for the identification of at least four monophyletic groups in Palaemon; two of which are monospecific at the moment. Based on the present results, it may become necessary to establish two new genera (to accommodate Palaemon concinnus and Palaemon mercedae, respectively), as well as re‐erect the genus Alaocaris Holthuis, 1949 for Palaemon antrorum, potentially including a further six American species.  相似文献   

12.
The bulbuls comprise an ecologically important group of frugivorous, seed‐dispersing birds found in Asia and Africa. Although several studies have examined the phylogenetic relationships of subsets of bulbul species, a comprehensive phylogeny of the family Pycnonotidae has hitherto been lacking. We used publicly available sequences generated from previous phylogenetic studies, augmented by new sequences from several unstudied taxa, to create a supermatrix from which to infer the phylogeny of the family. In all, we compared 121 of the 130 bulbul species. Our tree supports the monophyly of the family and comprises an exclusively African and a predominantly Asian clade. Several genera were found not to be monophyletic and we suggest taxonomic changes to provide a more accurate classification based on phylogeny.  相似文献   

13.
14.
The phylogeny of the Vitrinidae is reconstructed in a cladistic analysis based on characters of the genitalia, the copulation behaviour and the radula. The genera with an atrial stimulator turned out to be the earliest branches of the Vitrinidae, whereas the genera with a glandula amatoria form a monophyletic, taxonomically apomorphic group. The differences between the proposed phylogeny and previous hypotheses are discussed. The ancestral areas of the Vitrinidae and its sister group, the limacoid slugs Boettgerillidae–Limacidae–Agriolimacidae, are estimated using weighted ancestral area analysis. The Vitrinidae and the limacoid slugs might have originated by a vicariance event between Central Europe and the Near East. © 2002 The Linnean Society of London. Zoological Journal of the Linnean Society , 2002, 134 , 347–358.  相似文献   

15.
Epicaridean isopods are parasitic on other crustaceans. They represent a diverse group of highly derived taxa in two superfamilies and 10 families. Little work has been done on the phylogeny of these parasites because of the difficulty in defining homologous characters for adults above the genus level. The females exhibit morphological reduction of characters and the males have few distinguishing characters. Moreover, epicarideans have only rarely been included in past studies of isopod phylogeny. Our objective was to derive a phylogeny of epicaridean taxa based on 18S rDNA, then use that phylogeny to examine the relationships of the bopyrid subfamilies, bopyroid families and epicarideans to cymothoid isopods. We tested the monophyly of the Epicaridea, evaluated hypotheses on relationships among epicaridean families and subfamilies, examined the evolution of the abdominal mode of infestation on caridean, gebiidean, axiidean and anomuran hosts and examined coevolution between epicarideans and their crustacean hosts. The molecular phylogeny indicated that Epicaridea were monophyletic with respect to Cymothooidea. Bopyroidea formed a monophyletic group without Dajidae and Entophilinae (now as Entophilidae). Both latter taxa grouped with Cryptoniscoidea, and this group was the sister taxon to the redefined Bopyroidea in all trees. The bopyrid subfamily Ioninae is the sister taxon to the other bopyrid subfamilies (except Entophilidae). Ioninae was elevated to family status but found not to be monophyletic; a new subfamily, Keponinae, was erected for all genera formerly placed in Ioninae except the type genus. The abdominal mode of parasitism appears to have evolved independently among the subfamilies. Coevolution between host and parasite phylogenies showed extensive incongruence, indicating frequent host-switching as a general pattern in Epicaridea.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:30ECFB13-2795-494E-AABE-6B5F84A57A67  相似文献   

16.
17.
Conoesucidae (Trichoptera, Insecta) are restricted to SE Australia, Tasmania and New Zealand. The family includes 42 described species in 12 genera, and each genus is endemic to either New Zealand or Australia. Although monophyly has been previously assumed, no morphological characters have been proposed to represent synapomorphies for the group. We collected molecular data from two mitochondrial genes (16S and cytochrome oxidase I), one nuclear gene (elongation factor 1-α) (2237–2277 bp in total), and 12 morphological characters to produce the first phylogeny of the family. We combined the molecular and morphological characters and performed both a maximum parsimony analysis and a Bayesian analysis to test the monophyly of the family, and to hypothesize the phylogeny among its genera. The parsimony analysis revealed a single most parsimonious tree with Conoesucidae being a monophyletic taxon and sistergroup to the Calocidae. The Bayesian inference produced a distribution of trees, the consensus of which is supported with posterior probabilities of 100% for 15 out of 22 possible ingroup clades including the most basal branch of the family, indicating strong support for a monophyletic Conoesucidae. The most parsimonious tree and the tree from the Bayesian analysis were identical except that the ingroup genus Pycnocentria changed position by jumping to a neighbouring clade. Based on the assumption that the ancestral conoesucid species was present on both New Zealand and Australia, a biogeographical analysis using the dispersal-vicariance criteria demonstrated that one or two (depending on which of the two phylogenetic reconstructions were applied) sympatric speciation events took place on New Zealand prior to a single, late dispersal from New Zealand to Australia.  相似文献   

18.
The genera Parasesarma and Perisesarma are common inhabitants of mangroves and estuaries of the Indo-West Pacific. These, overall similar, genera of sesarmid crabs can be told apart by the presence or absence of an anterolateral tooth, but recent and ongoing studies show that they are not reciprocally monophyletic. In recent years, detailed morphological studies have revealed a surprising number of undescribed new species within these genera. In the present paper, we describe a new species of the genus Parasesarma from the relatively poorly studied Persian Gulf. So far, these specimens had been referred to as Parasesarma plicatum (Latreille, 1803), but morphological and genetic characteristics clearly allow separation of the two species. Consequently, the species from the Persian Gulf is here described as new and morphological and mitochondrial genetic characters are provided that allow recognition of the species.  相似文献   

19.
The lichen-forming genus Porpidia (Porpidiaceae, Ascomycota) provides excellent opportunities for evolutionary, reproductive, and ecological studies of crustose epilithic lichen symbioses. However, despite the fact that the genus itself seemed to be clearly delimited, the group was thought to be a hopeless case with regard to intrageneric relationships and species delimitations due to apparently rampant homoplasy throughout most character systems. Contrary to the situation for non-molecular data, a robust and generally well-resolved phylogeny was recovered based on DNA-sequence data. Separate and combined analyses of nuclear ribosomal RNA large subunit and nuclear beta-tubulin gene fragments were performed using maximum parsimony, maximum likelihood, and Bayesian approaches. Branch support was estimated using non-parametic bootstrapping and posterior probabilities, while monophyly of a priori defined groups was tested using posterior probabilities. The results reveal a highly supported "Porpidia sensu lato," however, Porpidia itself is not monophyletic. Several smaller genera of the Porpidiaceae and probably the large genus Lecidea (Lecideaceae) are nested within the group. Most taxa analyzed fall into one of four major subgroups within Porpidia s.l., though the basal relationships among these subgroups could not be supported. This phylogeny will make it possible to re-evaluate morphological and chemical characters in the group, and to conduct detailed studies of species delimitations within the monophyletic subgroups.  相似文献   

20.
Phylogeny and classification of Marantaceae   总被引:1,自引:0,他引:1  
Relationships of Marantaceae were estimated from nucleotide sequence variation in the rps16 intron (plastid DNA) and from morphological characters. Fifty-nine species (21 genera) formed the ingroup, and 12 species (12 genera) of other Zingiberales formed the outgroup. There is no support for the traditional subdivision of Marantaceae into a triovulate and a uniovulate tribe or the informal groups previously proposed. The so-called Donax group forms a paraphyletic grade that is basal within Marantaceae. Thalia appears as the distal branch of this grade, but its position is not supported in jackknife analysis. The so-called Calathea group is monophyletic in all shortest trees but not supported with greater than 50% jackknife. The genus Calathea appears to be paraphyletic. The Maranta and Phrynium groups are clearly polyphyletic. Maranta, Koernickanthe , and genera of the Mymsma group, all neotropical, form a strongly supported monophyletic group. The sister of this group is the palaeotropical genus Halopegia. Koernickanthe is nested within Maranta , as this genus is traditionally circumscribed. The African genera Ataenidia and Marantochloa form a strongly supported clade in which Ataenidia is the sister group to Marantochloa . Based on phylogeny it is concluded that Africa, in spite of being much poorer in species, is the most likely ancestral area of Marantaceae  相似文献   

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