Phylogenetic relationships among species of Contracaecum Railliet & Henry, 1912 and Phocascaris Høst, 1932 (Nematoda[ratio ]Ascaridoidea) based on nuclear rDNA sequence data

Parasitology ◽  
2000 ◽  
Vol 121 (4) ◽  
pp. 455-463 ◽  
Author(s):  
S. A. NADLER ◽  
S. D'AMELIO ◽  
H.-P. FAGERHOLM ◽  
B. BERLAND ◽  
L. PAGGI
Keyword(s):  
Dna Sequences ◽  
Phylogenetic Trees ◽  
Sequence Data ◽  
Large Subunit ◽  
Strong Support ◽  
Structural Features ◽  
Nominal Species ◽  
Phylogenetic Hypothesis ◽  
Natural Group ◽  
Phocid Seals

Nuclear-encoded large-subunit ribosomal DNA sequences were used to infer a phylogenetic hypothesis for 17 taxa (16 nominal species) of the genera Contracaecum and Phocascaris. Phylogenetic trees based on these data have been used to assess the validity of the taxonomic distinction between these genera, which was based on the presence or absence of certain structural features, rather than on explicit hypotheses of evolutionary history. Phylogenetic hypotheses based on parsimony, likelihood, and neighbor-joining analyses of these sequence data strongly support the hypothesis that species of Phocascaris are nested within the clade of Contracaecum species hosted by phocid seals, and are more closely related to species of the Contracaecum osculatum complex than to other Contracaecum species. Alternative tree topologies representing Phocascaris as not nested within the C. osculatum complex were significantly worse interpretations of these sequence data. Phylogenetic analysis also provides strong support for the monophyly of all taxa (Contracaecum and Phocascaris) from phocid seals, which is consistent with Berland's (1964) proposal that such species form a natural group; however, his proposal to recognize all species in phocid seals as Phocascaris, with all species from birds as Contracaecum would result in a paraphyletic Contracaecum, according to the molecular phylogenetic hypothesis.

Phylogeny of the rust fungi: an approach using nuclear large subunit ribosomal DNA sequences

2003 ◽  
Vol 81 (1) ◽  
pp. 12-23 ◽  
Author(s):  
Wolfgang Maier ◽  
Dominik Begerow ◽  
Michael Weiß ◽  
Franz Oberwinkler
Keyword(s):  
Ribosomal Dna ◽  
Dna Sequences ◽  
Sequence Data ◽  
Large Subunit ◽  
Rust Fungi ◽  
Monophyletic Group ◽  
Neighbor Joining ◽  
Natural Group ◽  
Outgroup Species ◽  
Large Subunit Rdna

Sequence data from nuclear large subunit ribosomal DNA was used to infer phylogenetic relationships of selected genera of the Uredinales. We investigated 52 rust fungi representing nine families and three outgroup species. Neighbor joining analysis and a Bayesian method of phylogenetic inference using Monte Carlo Markov chains confirm the rust fungi as a natural group and indicate that Puccinia, Uromyces, Endophyllum, and Cumminsiella have a common origin. The autoecious Rosaceae-rusts Phragmidium, Kuehneola, Triphragmium, and Trachyspora are a monophyletic group. The gasteroid genus Ochropsora is closely related to Tranzschelia. While the Pucciniastreae sensu Dietel (1938) is recognized as a monophyletic group in neighbor joining analysis, the Pucciniaceae s.l. (Dietel 1928) is supported by Bayesian analysis. The following genera appear to be monophyletic: Chrysomyxa, Coleosporium, Cronartium, Gymnosporangium, Melampsora, Phragmidium, and Tranzschelia, whereas the genera Puccinia, Pucciniastrum, Thekopsora, and Uromyces are not.Key words: molecular phylogeny, systematics, nuclear large subunit rDNA, Basidiomycota, Urediniomycetes, Uredinales.

scholarly journals Phylogeny and PCR Identification of Clinically Important Zygomycetes Based on Nuclear Ribosomal-DNA Sequence Data

1999 ◽  
Vol 37 (12) ◽  
pp. 3957-3964 ◽  
Author(s):  
Kerstin Voigt ◽  
Elizabeth Cigelnik ◽  
Kerry O'donnell
Keyword(s):  
Dna Sequence ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Sequence Data ◽  
Large Subunit ◽  
Gene Tree ◽  
Strong Support ◽  
Nuclear Ribosomal Dna ◽  
Syncephalastrum Racemosum ◽  
Dna Sequence Data

A molecular database for all clinically important Zygomycetes was constructed from nucleotide sequences from the nuclear small-subunit (18S) ribosomal DNA and domains D1 and D2 of the nuclear large-subunit (28S) ribosomal DNA. Parsimony analysis of the aligned 18S and 28S DNA sequences was used to investigate phylogenetic relationships among 42 isolates representing species of Zygomycetes reported to cause infections in humans and other animals, together with commonly cultured contaminants, with emphasis on members of the Mucorales. The molecular phylogeny provided strong support for the monophyly of the Mucorales, exclusive of Echinosporangium transversale andMortierella spp., which are currently misclassified within the Mucorales. Micromucor ramannianus, traditionally classified within Mortierella, and Syncephalastrum racemosum represent the basal divergences within the Mucorales. Based on the 18S gene tree topology, Absidia corymbiferaand Rhizomucor variabilis appear to be misplaced taxonomically. A. corymbifera is strongly supported as a sister group of the Rhizomucor miehei-Rhizomucor pusillusclade, while R. variabilis is nested withinMucor. The aligned 28S sequences were used to design 13 taxon-specific PCR primer pairs for those taxa most commonly implicated in infections. All of the primers specifically amplified DNA of the size predicted based on the DNA sequence data from the target taxa; however, they did not cross-react with phylogenetically related species. These primers have the potential to be used in a PCR assay for the rapid and accurate identification of the etiological agents of mucormycoses and entomophthoromycoses.

scholarly journals Morphology, genetic characterization and molecular phylogeny of pinworm Skrjabinema longicaudatum n. sp. (Oxyurida: Oxyuridae) from the endangered Tibetan antelope Pantholops hodgsonii (Abel) (Artiodactyla: Bovidae)

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Yi-Fan Cao ◽  
Hui-Xia Chen ◽  
Yang Li ◽  
Dang-Wei Zhou ◽  
Shi-Long Chen ◽  
...  
Keyword(s):  
New Species ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Small Subunit ◽  
Sister Relationship ◽  
Tibetan Antelope ◽  
A New Species

Abstract Background The Tibetan antelope Pantholops hodgsonii (Abel) (Artiodactyla: Bovidae) is an endangered species of mammal endemic to the Qinghai-Tibetan Plateau. Parasites and parasitic diseases are considered to be important threats in the conservation of the Tibetan antelope. However, our present knowledge of the composition of the parasites of the Tibetan antelope remains limited. Methods Large numbers of nematode parasites were collected from a dead Tibetan antelope. The morphology of these nematode specimens was observed using light and scanning electron microscopy. The nuclear and mitochondrial DNA sequences, i.e. small subunit ribosomal DNA (18S), large subunit ribosomal DNA (28S), internal transcribed spacer (ITS) and cytochrome c oxidase subunit 1 (cox1), were amplified and sequenced for molecular identification. Moreover, phylogenetic analyses were performed using maximum likelihood (ML) inference based on 28S and 18S + 28S + cox1 sequence data, respectively, in order to clarify the systematic status of these nematodes. Results Integrated morphological and genetic evidence reveals these nematode specimens to be a new species of pinworm Skrjabinema longicaudatum (Oxyurida: Oxyuridae). There was no intraspecific nucleotide variation between different individuals of S. longicaudatum n. sp. in the partial 18S, 28S, ITS and cox1 sequences. However, a high level of nucleotide divergence was revealed between the new species and its congeners in 28S (8.36%) and ITS (20.3–23.7%) regions, respectively. Molecular phylogenetic results suggest that the genus Skrjabinema should belong to the subfamily Oxyurinae (Oxyuroidea: Oxyuridae), instead of the subfamily Syphaciidae or Skrjabinemiinae in the traditional classification, as it formed a sister relationship to the genus Oxyuris. Conclusions A new species of pinworm Skrjabinema longicaudatum n. sp. (Oxyurida: Oxyuridae) is described. Skrjabinema longicaudatum n. sp. represents the first species of Oxyurida (pinworm) and the fourth nematode species reported from the Tibetan antelope. Our results contribute to the knowledge of the species diversity of parasites from the Tibetan antelope, and clarify the systematic position of the genus Skrjabinema.

Phylogenetic studies of Saprolegniomycetidae and related groups based on nuclear large subunit ribosomal DNA sequences

2000 ◽  
Vol 77 (12) ◽  
pp. 1790-1800 ◽  
Author(s):  
Alexandra Riethmüller ◽  
Michael Weiß ◽  
Franz Oberwinkler
Keyword(s):  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Bootstrap Method ◽  
Large Subunit ◽  
Phytophthora Megasperma ◽  
Parsimony Method ◽  
Natural Group ◽  
Maximum Parsimony Method ◽  
Phylogenetic Studies ◽  
Main Emphasis

To reveal phylogenetic relationships within the Peronosporomycetes (Oomycetes), we sequenced a part of the nuclear rDNA coding for the ribosomal large subunit of 46 Peronosporomycetes species and one representative of the Xanthophyta. The main emphasis of our study was put on the phylogenetic relationships within the Saprolegniomycetidae. We supplemented our data with a sequence of Phytophthora megasperma Drechsler from GenBank. Two sets of sequences were analysed using the neighbor-joining method, statistically supported by the bootstrap method, as well as the maximum parsimony method. Our results are well compatible with the tripartite subclassification of the Peronosporomycetes into Saprolegniomycetidae, Rhipidiomycetidae and Peronosporomycetidae, as well as with the placement of the orders Saprolegniales and Leptomitales in the Saprolegniomycetidae. Pachymetra chaunorhiza Croft & Dick, which has been placed in the Sclerosporales, was grouped within the Saprolegniales. Within the Peronosporomycetidae, the orders Peronosporales and Pythiales could not be separated. There are indications that Phytophthora de Bary and the Peronosporales form a common natural group. The genus Achlya Nees proved to be a heterogeneous group.

On the phylogeny of Ophiostoma, Ceratocystis s.s., and Microascus, and relationships within Ophiostoma based on partial ribosomal DNA sequences

1993 ◽  
Vol 71 (9) ◽  
pp. 1249-1265 ◽  
Author(s):  
G. Hausner ◽  
J. Reid ◽  
G. R. Klassen
Keyword(s):  
Dna Sequences ◽  
Sequence Data ◽  
Large Subunit ◽  
Small Subunit ◽  
Data Set ◽  
Rdna Sequences ◽  
Morphological Criteria ◽  
Small Subunit Rdna ◽  
Rdna Sequence Data ◽  
Large Subunit Rdna

Phylogenetic analysis of partial rDNA sequences suggests that Ophiostoma should remain the sole genus of the Ophiostomataceae, and this should be the sole family within the Ophiostomatales, whereas Ceratocystis s.s. would be best disposed within the Microascales. Although morphological criteria suggest that the genus Ophiostoma is heterogeneous, analysis of partial small subunit rDNA sequence data shows that Ophiostoma (excluding O. roraimense) represents a monophyletic taxon. Analysis of a partial large subunit rDNA data set, which included sequences from 55 species assignable to Ophiostoma, failed to support the strict subdivision of the genus based on either ascospore characters or the nature of the anamorph. Key words: Ceratocystis, Microascus, Ophiostoma, partial rDNA sequences, phylogeny.

Strelitziana sarbhoyi sp. nov. (Strelitzianaceae, Chaetothyriales), from North-Western Himalayas, India, described based on morphology and molecular phylogeny

Phytotaxa ◽  
2019 ◽  
Vol 427 (1) ◽  
pp. 51-59
Author(s):  
SHIWALI RANA ◽  
SANJAY KUMAR SINGH ◽  
PARAS NATH SINGH
Keyword(s):  
Phylogenetic Tree ◽  
Dna Sequences ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Culture Collection ◽  
Fungal Culture ◽  
Western Himalayas ◽  
Holotype Specimen ◽  
North Western

Strelitziana sarbhoyi is established as a new species to accommodate a phylloplane fungus isolated from Mallotus philippensis collected from Kangra region of North-Western Himalayas, Himachal Pradesh. The identity of the fungus is confirmed based on the asexual-morphs, cultural characteristics and phylogenetic analyses of the internal transcribed spacer (ITS) rDNA and partial nuclear ribosomal 28S large subunit (LSU) sequence data. The placement of S. sarbhoyi in the phylogenetic tree was determined based on DNA sequences from authenticated isolates of Strelitziana. Strelitziana sarbhoyi shows nearly 94% similarity with other known species of Strelitziana. Area description is provided for the proposed taxon along with microscopic images, and a phylogenetic tree. This is probably the first report of Strelitziana from India. Holotype specimen (dried voucher culture) is deposited in the Ajrekar Mycological Herbarium (AMH), and an ex-type culture is deposited in National Fungal Culture Collection of India (NFCCI).

Molecular and morphological evidence indicates that Pseudorhabdosynochus lantauensis (Monogenea: Diplectanidae) represents two species

Parasitology ◽  
2005 ◽  
Vol 130 (6) ◽  
pp. 669-677 ◽  
Author(s):  
X. Y. WU ◽  
N. B. CHILTON ◽  
X. Q. ZHU ◽  
M. Q. XIE ◽  
A. X. LI
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Strong Support ◽  
Morphological Characteristics ◽  
Sufficient Evidence ◽  
Bootstrap Support ◽  
Morphological Evidence ◽  
Lsu Rdna ◽  
Epinephelus Coioides

Sequences of the first internal transcribed spacer (ITS-1) and the D1-D3 domains of the large subunit (LSU) of the ribosomal DNA (rDNA) were determined for multiple specimens of 4 operational taxonomic units (OTUs) of the monogenean, Pseudorhabdosynochus lantauensis. OTUs were defined based on their collecting localities, host and/or morphological characteristics. All P. lantauensis specimens of one group (OTUs 1 and 3) differed in their sequences of the ITS-1 and partial LSU rDNA when compared with specimens of a second group (OTUs 2 and 4) by 12% and 2%, respectively. Results of the phylogenetic analyses of the LSU rDNA sequence data showed total (100%) bootstrap support for the separation of P. lantauensis into 2 distinct clades. At least 11 of the 18 nucleotide differences in the LSU sequence between the two P. lantauensis clades were derived (i.e. autapomorphic) characters when the morphologically distinct species, P. epinepheli and P. coioidesis, were used as outgroups. Furthermore, there were several autapomorphic character states for each P. lantauensis clade. This provides sufficient evidence to reject the null hypothesis that P. lantauensis represents a single species. Morphological and morphometric differences between these two clades provided additional strong support for the separation of P. lantauensis into two species. These two parasite species were found to co-exist on one of the two species of serranid fish (i.e. Epinephelus coioides) examined in the South China Sea (Guangdong Province, China).

scholarly journals Two new asexual genera and six new asexual species in the family Microthyriaceae (Dothideomycetes, Ascomycota) from China

MycoKeys ◽  
2021 ◽  
Vol 85 ◽  
pp. 1-30
Author(s):  
Min Qiao ◽  
Hua Zheng ◽  
Ji-Shu Guo ◽  
Rafael F. Castañeda-Ruiz ◽  
Jian-Ping Xu ◽  
...  
Keyword(s):  
New Taxa ◽  
Dna Sequences ◽  
Sequence Data ◽  
Southern China ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Aquatic Hyphomycetes ◽  
Internal Transcribed Spacers ◽  
The Family

The family Microthyriaceae is represented by relatively few mycelial cultures and DNA sequences; as a result, the taxonomy and classification of this group of organisms remain poorly understood. During the investigation of the diversity of aquatic hyphomycetes from southern China, several isolates were collected. These isolates were cultured and sequenced and a BLAST search of its LSU sequences against data in GenBank revealed that the closest related taxa are in the genus Microthyrium. Phylogenetic analyses, based on the combined sequence data from the internal transcribed spacers (ITS) and the large subunit (LSU), revealed that these isolates represent eight new taxa in Microthyriaceae, including two new genera, Antidactylariagen. nov. and Isthmomycesgen. nov. and six new species, Antidactylaria minifimbriatasp. nov., Isthmomyces oxysporussp. nov., I. dissimilissp. nov., I. macrosporussp. nov., Triscelophorus anisopterioideussp. nov. and T. sinensissp. nov. These new taxa are described, illustrated for their morphologies and compared with similar taxa. In addition, two new combinations are proposed in this family.

scholarly journals Three, two, one! Revision of the long-bodied sphaerodorids (Sphaerodoridae, Annelida) and synonymization ofEphesiella,EphesiopsisandSphaerodorum

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5783 ◽  
Author(s):  
María Capa ◽  
Torkild Bakken ◽  
Karin Meißner ◽  
Arne Nygren
Keyword(s):  
Dna Sequences ◽  
Nuclear Dna ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Intraspecific Variability ◽  
Morphological Data ◽  
Nominal Species ◽  
Type Specimens ◽  
Diagnostic Features ◽  
28S Rdna Sequence

BackgroundLong-bodied sphaerodorids (Annelida, Sphaerodoridae) is the common name for members of the three closely and morphologically homogenous currently accepted genera of benthic marine bristle worms:Ephesiella,EphesiopsisandSphaerodorum. Members of this group share the presence of two dorsal and longitudinal rows of macrotubercles with terminal papillae, and two longitudinal rows of microtubercles, features that are unique among sphaerodorids. Genera are distinguished by the chaetae morphology. Members ofEphesiellaare characterised by having compound chaetae (except, sometimes, simple chaetae in the first chaetigers),Sphaerodorumbear only simple chaetae, andEphesiopsishave both compound and simple chaetae in all parapodia.MethodsMitochondrial (partial COI and 16S rDNA) and nuclear (partial 18S rDNA and 28S rDNA) sequence data of long-bodied sphaerodorids with compound and simple chaetae, and an outgroup of additional seven sphaerodorid species were analysed separately and in combination using Bayesian inference (BA), and Maximum Likelihood (ML) methods. Long-bodied sphaerodorids from around the world (including type specimens) were examined under a range of optical equipment in order to evaluate putative generic and specific diagnostic features, in addition to intraspecific variability.ResultsPhylogenetic analyses of mitochondrial and nuclear DNA sequences of specimens identified asEphesiellaandSphaerodorum,based on chaeta morphology, were performed.SphaerodorumandEphesiellawere recovered as paraphyletic and nested within each other. Revision of current nominal species diagnostic features are performed and discussed.DiscussionResults contradict current generic definitions. Recovery of paraphyletic compound and simple chaetae clades urge the synonymization of these two genera of long-bodied sphaerodorids. Morphological data also suggest the synonymization ofEphesiopsis.

Kamalia indica, a new genus and species belonging to Diaporthales (Ascomycota, Fungi) described based on morphology and molecular phylogeny

Phytotaxa ◽  
2019 ◽  
Vol 425 (4) ◽  
pp. 233-243
Author(s):  
SHIWALI RANA ◽  
SANJAY KUMAR SINGH
Keyword(s):  
Dna Sequences ◽  
Internal Transcribed Spacer ◽  
New Genus ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Type Specimen ◽  
Morphological Description ◽  
Fungal Culture ◽  
Internal Transcribed Spacer Region

A fungal taxa isolated from leaf spots of Mallotus philippensis from Kangra district of North-Western Himalayan region of India is established as a new genus based on morphological characters of asexual-morphs, cultural characteristics and phylogenetic analyses of the partial nuclear ribosomal 28S large subunit (LSU) and internal transcribed spacer (ITS) rDNA sequence data. The generic placement of the genus has been determined based on DNA sequences from authenticated isolates. The present taxon has turned out to be distinct, showing nearly 90% identity with other known genera in Diaporthales based on nrDNA internal transcribed spacer region. The morphological description is provided for the new taxa and compared with the similar taxa belonging to the order Diaporthales. The culture was found to show heavy sporulation in all kind of media. The type specimen and ex type culture have been deposited in the Ajrekar Mycological Herbarium (AMH) and National Fungal Culture Collection of India (NFCCI-WDCM 932), respectively.

Sign in / Sign up

Export Citation Format

Share Document