On the subdivision of Ceratocystis s.l., based on partial ribosomal DNA sequences

1993 ◽  
Vol 71 (1) ◽  
pp. 52-63 ◽  
Author(s):  
G. Hausner ◽  
J. Reid ◽  
G. R. Klassen
Keyword(s):  
Key Words ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Cell Walls ◽  
Large Subunit ◽  
Rdna Sequences

Analyses of partial rDNA sequences from both the small and large subunit genes of species of Ceratocystis s.l. support the contention that species that lack Chalara anamorphs, are resistant to cycloheximide, and have rhamnose in their cell walls should be assigned to Ophiostoma, whereas only species with Chalara anamorphs should be accommodated in Ceratocystis s.s. The data also show that Ceratocystiopsis is polyphyletic, and Sphaeronaemella fimicola appears to have little relation to either Ceratocystis or Ophiostoma. Key words: Ceratocystis, Ophiostoma, phylogeny, partial rDNA sequences.

scholarly journals Sequences of psychrophilic fungi amplified from glacier-preserved ascolichens

2000 ◽  
Vol 78 (11) ◽  
pp. 1450-1459 ◽  
Author(s):  
Paula T DePriest ◽  
Natalia V Ivanova ◽  
Dianne Fahselt ◽  
Vagn Alstrup ◽  
Andrea Gargas
Keyword(s):  
Phylogenetic Analysis ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Large Subunit ◽  
Ice Core ◽  
Small Subunit ◽  
Rdna Sequences ◽  
Three Samples ◽  
Tyrolean Iceman ◽  
Small Subunit Ribosomal Dna

Ribosomal DNA sequences were amplified from subfossils of the ascolichen Umbilicaria cylindrica (L.) Delise ex Duby collected at the ablating edges of Greenland glaciers. Surprisingly, phylogenetic analysis indicated that the amplified rDNA sequences were not closely related to those of the lichen-forming fungus but rather represented two groups of psychrophilic basidiomycetes (orders Cystofilobasidiales and Sporidiales) and one group of ascomycetes (order Leotiales). Two of these groups, the Sporidiales and the Leotiales, include other fungi previously detected in DNA extracted from the grass clothing of the Tyrolean Iceman desiccated and frozen for over 3000 years and also in 2000- and 4000-year-old ice core samples from northern Greenland. Large subunit ribosomal DNA sequences representing the group Cystofilobasidiales were nearly identical to those of the basidioyeast saprobe Mrakia frigida. The adjacent internal transcribed spacer sequence was more than 98% similar to those from three samples of U. cylindrica from different sites that had been subjected to ice burial for various lengths of time, suggesting they also were Mrakia sequences. Although ancient contamination of multiple U. cylindrica specimens with fungi such as Mrakia cannot be ruled out, it is more probable that saprobic colonization of the subfossil tissues by psychrophilic fungi proceeded during recent ice melt.Key words: ancient DNA, small subunit ribosomal DNA, 18S ribosomal DNA, phylogenetic analysis, psychrophilic fungi, lichen-forming fungi.

A phylogeny inferred from large-subunit (26S) ribosomal DNA sequences suggests that the family Dasypogonaceae is closely aligned with the Restionaceae allies

2002 ◽  
Vol 15 (6) ◽  
pp. 749 ◽  
Author(s):  
Ray Neyland
Keyword(s):  
Phylogenetic Analysis ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Large Subunit ◽  
Monophyletic Group ◽  
26S Rdna ◽  
Rdna Sequences ◽  
Australian Family ◽  
The Family

The Dasypogonaceae is a small Australian family composed of four genera. Previous systematic studies have failed to place the Dasypogonaceae with confidence. The present phylogenetic analysis, inferred from large-subunit (26S) rDNA sequences, strongly suggests that the Dasypogonaceae form a monophyletic group with the taxa referred to as the Restionaceae allies (i.e. Anarthriaceae, Centrolepidaceae, Ecdeiocoleaceae).

scholarly journals Taxonomic relationships in the genus <i>Ammonia</i> (Foraminifera) based on ribosomal DNA sequences

2000 ◽  
Vol 19 (1) ◽  
pp. 85-95 ◽  
Author(s):  
Maria Holzmann ◽  
Jan Pawlowski
Keyword(s):  
Ribosomal Dna ◽  
Dna Sequences ◽  
Large Subunit ◽  
Morphological Variability ◽  
Small Subunit ◽  
Lsu Rdna ◽  
Taxonomic Relationships ◽  
Rdna Sequences ◽  
Ecological Features ◽  
Genotypic Group

Abstract. The genus Ammonia is a common benthic foraminifer which is widely distributed in nearshore marine environments. Its large morphological variability causes considerable difficulties in species identification. In the present study, we investigated taxonomic relationships in Ammonia by using a molecular approach based on ribosomal DNA sequences. We obtained 149 partial large subunit ribosomal DNA (LSU rDNA) sequences and 23 small subunit ribosomal DNA (SSU rDNA) sequences from 88 living Ammonia specimens which were collected from free-living populations in 14 localities. Sequence analysis revealed the presence of eight distinct genotypic groups (T1–T7, T9) and one distinct genotype that is represented by one specimen (T8). Examination of morphological characters shows that only one genotypic group can be clearly distinguished by its morphology. Biogeographical and ecological features are used for an additional characterization and it seems that the different groups live in relatively well defined environmental conditions and that only one genotypic group is cosmopolitan, while the others have a rather restricted geographical distribution. According to our study, three of the genotypic groups can be regarded as distinct species.

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.

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.

scholarly journals Phylogenetic Relationships of Agaric Fungi Based on Nuclear Large Subunit Ribosomal DNA Sequences

2000 ◽  
Vol 49 (2) ◽  
pp. 278-305 ◽  
Author(s):  
Jean-Marc Moncalvo ◽  
François M. Lutzoni ◽  
Stephen A. Rehner ◽  
Jacqui Johnson ◽  
Rytas Vilgalys
Keyword(s):  
Ribosomal Dna ◽  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Large Subunit

A phylogenetic study of the Micarea prasina group shows that Micarea micrococca includes three distinct lineages

2009 ◽  
Vol 42 (1) ◽  
pp. 7-21 ◽  
Author(s):  
Paweł CZARNOTA ◽  
Beata GUZOW-KRZEMIŃSKA
Keyword(s):  
Maximum Likelihood ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Maximum Parsimony ◽  
Small Subunit ◽  
Sister Species ◽  
Phylogenetic Study ◽  
Rdna Sequences ◽  
Small Subunit Ribosomal Dna

AbstractThe phylogeny of the Micarea prasina group was investigated using mitochondrial small subunit ribosomal DNA sequences from 14 taxa representing this group, four other members of the genus Micarea, and Psilolechia lucida as an outgroup. A total of 31 new mtSSU rDNA sequences were generated, including 10 from the M. micrococca complex. Bayesian, maximum parsimony (MP) and maximum likelihood (ML) methods were used to analyse the data. The results show that M. micrococca is not monophyletic and forms three strongly supported lineages: 1) M. micrococca s. str., 2) M. byssacea (Th. Fr.) Czarnota, Guzow-Krzemińska & Coppins comb. nov., and 3) a putative taxon that requires further studies. Micarea viridileprosa is a sister species to M. micrococca s. str. and the recently described M. nowakii is a sister species to M. prasina s. str. The placement of M. tomentosa within the M. prasina group is confirmed. Micarea hedlundii appears to be more closely related to the M. micrococca complex than M. prasina s. str. Descriptions, illustrations, taxonomic remarks, distribution and habitat data for M. micrococca s. str. and M. byssacea are provided. A lectotype for Biatora byssacea Hampe non Zwackh and a neotype for Catillaria prasina β [var.] byssacea are selected.

A preliminary overview of the Diaporthales based on large subunit nuclear ribosomal DNA sequences

Mycologia ◽  
2002 ◽  
Vol 94 (6) ◽  
pp. 1017-1031 ◽  
Author(s):  
Lisa A. Castlebury ◽  
Amy Y. Rossman ◽  
Walter J. Jaklitsch ◽  
Larissa N. Vasilyeva
Keyword(s):  
Ribosomal Dna ◽  
Dna Sequences ◽  
Large Subunit ◽  
Nuclear Ribosomal Dna
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