scholarly journals Molecular phylogenies support taxonomic revision of three species of Laurencia (Rhodomelaceae, Rhodophyta), with the description of a new genus

Author(s):  
Florence Rousseau ◽  
Delphine Gey ◽  
Akira Kurihara ◽  
Christine A. Maggs ◽  
Julie Martin-Lescanne ◽  
...  

The systematics of the Laurencia complex was investigated using a taxon-rich data set including the chloroplast ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene only and a character-rich data set combining mitochondrial cytochrome oxidase 1 (COI-5P), the rbcL marker, and the nuclear large subunit of the ribosomal operon (LSU). Bayesian and ML analyses of these data sets showed that three species hitherto placed in the genus Laurencia J.V.Lamour. were not closely related to Laurencia s. str. Laurencia caspica Zinova & Zaberzhinskaya was the sister group of the remaining Osmundea Stackh. species, L. crustiformans McDermid joined Palisada and L. flexilis Setch. consisted of an independent lineage. In light of these results a new genus, Ohelopapa F.Rousseau, Martin-Lescanne, Payri & L.Le Gall gen. nov., is proposed to accommodate L. flexilis. This new genus is morphologically characterized by four pericentral cells in each vegetative axial segment; however, it lacks ‘corps en cerise’ in cortical cells and secondary pit connections between cortical cells, which are characteristic of Laurencia. Three novel combinations are proposed to render the classification closer to a natural system: Ohelopapa flexilis (Setch.) F.Rousseau, Martin-Lescanne, Payri & L.Le Gall comb. nov., Osmundea caspica (Zinova & Zaberzhinskaya) Maggs & L.M.McIvor comb. nov. and Palisada crustiformans (McDermid) A.R.Sherwood, A.Kurihara & K.W.Nam comb. nov.

1994 ◽  
Vol 7 (1) ◽  
pp. 57 ◽  
Author(s):  
JE Rodman ◽  
KG Karol ◽  
RA PRice ◽  
E Conti ◽  
KJ Systma

Nucleotide sequences (1452 base pairs) from the chloroplast gene for the large subunit of ribulose-1, 5-bisphosphate carboxylase/oxygenase (rbcL) were obtained for three species of Gyrostemon and Tersonia of the Australian endemic family Gyrostemonaceae. Phylogenetic reconstruction based on parsimony robustly allies the family with other mustard oil-producing plants in Dahlgren's expanded order Capparales. Within this clade, Gyrostemonaceae are the sister group to Resedaceae, but the sequence data provide only weak support for this particular linkage. The new molecular data corroborate recent embryological and ultrastructural findings for Gyrosternonaceae and confirm results from Rodman's cladistic analysis of traditional morphological features of these plants. The rbcL sequences for the three species of Gyrostemonaceae were consistent in possessing a stop codon ending at position 1452, well beyond the usual 1428 site for many dicots. An extended terminus for the rbcL gene appears to be a marker within the expanded order Capparales for a derived clade that comprises the traditional core Capparales (Brassicaceae, Capparaceae, Resedaceae and Tovariaceae) plus Gyrostemonaceae, the sister taxa Batis + Koeberlinia, and Limnanthaceae.


2012 ◽  
Vol 25 (6) ◽  
pp. 418 ◽  
Author(s):  
Roy E. Halling ◽  
Mitchell Nuhn ◽  
Todd Osmundson ◽  
Nigel Fechner ◽  
James M. Trappe ◽  
...  

Harrya is described as a new genus of Boletaceae to accommodate Boletus chromapes, a pink-capped bolete with a finely scabrous stipe adorned with pink scabers, a chrome yellow base and a reddish-brown spore deposit. Phylogenetic analyses of large-subunit rDNA and translation elongation factor 1α confirmed Harrya as a unique generic lineage with two species, one of which is newly described (H. atriceps). Some Chinese taxa were recently placed in a separate genus, Zangia, supported by both morphology and molecular data. Multiple accessions from Queensland, Australia, support the synonymy of at least three species in a separate Australian clade in the new genus, Australopilus. The truffle-like Royoungia is also supported as a separate lineage in this clade of boletes. Even though it lacks stipe characters, it possesses the deep, bright yellow to orange pigments in the peridium. Additional collections from Zambia and Thailand represent independent lineages of uncertain phylogenetic placement in the Chromapes complex, but sampling is insufficient for formal description of new species. Specimens from Java referable to Tylopilus pernanus appear to be a sister group of the Harrya lineage.


2012 ◽  
Vol 7 (1) ◽  
pp. 174-197 ◽  
Author(s):  
Heather Small ◽  
Kristine Kasianovitz ◽  
Ronald Blanford ◽  
Ina Celaya

Social networking sites and other social media have enabled new forms of collaborative communication and participation for users, and created additional value as rich data sets for research. Research based on accessing, mining, and analyzing social media data has risen steadily over the last several years and is increasingly multidisciplinary; researchers from the social sciences, humanities, computer science and other domains have used social media data as the basis of their studies. The broad use of this form of data has implications for how curators address preservation, access and reuse for an audience with divergent disciplinary norms related to privacy, ownership, authenticity and reliability.In this paper, we explore how the characteristics of the Twitter platform, coupled with an ambiguous and evolving understanding of privacy in networked communication, and divergent disciplinary understandings of the resulting data, combine to create complex issues for curators trying to ensure broad-based and ethical reuse of Twitter data. We provide a case study of a specific data set to illustrate how data curators can engage with the topics and questions raised in the paper. While some initial suggestions are offered to librarians and other information professionals who are beginning to receive social media data from researchers, our larger goal is to stimulate discussion and prompt additional research on the curation and preservation of social media data.


2019 ◽  
Vol 2 (2) ◽  
pp. 169-187 ◽  
Author(s):  
Ruben C. Arslan

Data documentation in psychology lags behind not only many other disciplines, but also basic standards of usefulness. Psychological scientists often prefer to invest the time and effort that would be necessary to document existing data well in other duties, such as writing and collecting more data. Codebooks therefore tend to be unstandardized and stored in proprietary formats, and they are rarely properly indexed in search engines. This means that rich data sets are sometimes used only once—by their creators—and left to disappear into oblivion. Even if they can find an existing data set, researchers are unlikely to publish analyses based on it if they cannot be confident that they understand it well enough. My codebook package makes it easier to generate rich metadata in human- and machine-readable codebooks. It uses metadata from existing sources and automates some tedious tasks, such as documenting psychological scales and reliabilities, summarizing descriptive statistics, and identifying patterns of missingness. The codebook R package and Web app make it possible to generate a rich codebook in a few minutes and just three clicks. Over time, its use could lead to psychological data becoming findable, accessible, interoperable, and reusable, thereby reducing research waste and benefiting both its users and the scientific community as a whole.


1995 ◽  
Vol 8 (4) ◽  
pp. 483 ◽  
Author(s):  
PY Ladiges ◽  
F Udovicic ◽  
AN Drinnan

Molecular (5S rDNA spacer and chloroplast DNA RnPs) and morphological data sets are informative at different levels of the eucalypt clade. They allow separate analysis of major subclades, the results of which, when combined, give a single, phylogenetic tree for Angophora Cav. and Eucalyptus L'Hér. For taxonomic revision, the tree supports the recognition of bloodwood eucalypts as monophyletic, but shows that informal subgenus Corymbia Pryor & Johnson is paraphyletic. The tree supports recognition of three major clades within the non-bloodwood eucalypts ('eudesmids', 'symphyomyrts' and 'monocalypts') and suggests relationships for taxa within each of these. Ovule and seed characters proved to be most informative in the morphological data set. The phylogenetic hypothesis suggests interpretations for homoplasious morphological characters, including parallel evolution of sepaline and petaline opercula (and associated stemonophore) and types of conflorescence.


2021 ◽  
Vol 908 (1) ◽  
pp. 012030
Author(s):  
M V Protopopova ◽  
N A Shvetsova ◽  
V V Pavlichenko

Abstract The methods of biological species identification using nucleotide sequences of short genome regions (DNA barcoding) are actively developed. The universal DNA barcode for plants remains to be discovered, and one of the leading candidates is the plastid gene of the large subunit of ribulose-bisphosphate carboxylase gene (rbcL). In our study, we estimated the part of rbcL gene as a possible marker for molecular identification of Rhaponticum carthamoides (Willd.) Iljin. Due to its officinal properties, the species is susceptible to uncontrolled and illegal harvesting from natural populations. Today, the species needs to be protected and therefore is included into the Red Data Books of the Russian Federation and certain regions. The study was carried out using plants from the natural populations sampled from the Khamar-Daban Ridge (South Siberia) and considering now as Rh. carthamoides var. chamarense (Peschkova) O S Zhirova. It was shown that rbcL gene can be used to identify Rh. carthamoides at least from the populations of the Khamar-Daban Ridge using a fragment of the maximum length or its 3’ region. Apparently, the 5’ region of the gene (rbcLa) most often used as DNA barcode for plants may be of lesser importance for Rh. carthamoides. The rbcL gene sequences can be also used for the development of approaches for Rh. carthamoides identification in the medicinal preparations and products containing dried tissues to prevent their falsification and illegal harvesting of this species. The combination of rbcL gene with additional markers seems to be highly desirable to create effective DNA barcodes for Rhaponticum species.


Genetics ◽  
1987 ◽  
Vol 116 (4) ◽  
pp. 613-621
Author(s):  
Koji Murai ◽  
Koichiro Tsunewaki

ABSTRACT The genus Avena contains five different chloroplast genomes, I-V. A physical map of chloroplast (ct) DNA of Avena sativa (type I chloroplast genome) was constructed using three restriction endonucleases, PstI, SalI and SmaI. This genome is ca. 135.5 kbp in size, and contains two inverted repeats of ca. 22.5 kbp each, separated by a large (ca. 79.0 kbp) and small (ca. 12.5 kbp) single copy region. The rbcL gene which codes for the large subunit of ribulose 1,5-bisphosphate carboxylase, was located in the map. Restriction fragment patterns of all five chloroplast genomes were compared, and among them five fragment size and five restriction site mutations were disclosed. Four site mutations were found in two or more chloroplast genomes, the other site and five fragment size mutations were specific to one or another of the chloroplast genomes. A dendrogram showing phylogenetic relationships among the five chloroplast genomes, based on the distribution of the common and specific mutations among them, indicates that chloroplast genome divergence characterized by three restriction site mutations occurred first between two diploid groups, each carrying A and C genome (nuclear), respectively, followed by further speciation in each group.


1995 ◽  
Vol 73 (S1) ◽  
pp. 649-659 ◽  
Author(s):  
François Lutzoni ◽  
Rytas Vilgalys

To provide a clearer picture of fungal species relationships, increased efforts are being made to include both molecular and morphological data sets in phylogenetic studies. This general practice in systematics has raised many unresolved questions and controversies regarding how to best integrate the phylogenetic information revealed by morphological and molecular characters. This is because phylogenetic trees derived using different data sets are rarely identical. Such discrepancies can be due to sampling error, to the use of an inappropriate evolutionary model for a given data set, or to different phylogenetic histories between the organisms and the molecule. Methods have been developed recently to test for heterogeneity among data sets, although none of these methods have been subjected to simulation studies. In this paper we compare three tests: a protocol described by Rodrigo et al., an adapted version of Faith's T-PTP test, and Kishino and Hasegawa's likelihood test. These tests were empirically compared using seven lichenized and nonlichenized Omphalina species and the related species Arrhenia lobata (Basidiomycota, Agaricales) for which nrDNA large subunit sequences and morphological data were gathered. The results of these three tests were inconsistent, Rodrigo's test being the only one suggesting that the two data sets could be combined. One of the three most parsimonious trees obtained from the combined data set with eight species is totally congruent with the relationships among the same eight species in an analysis restricted to the same portion of the nrDNA large subunit but extended to 26 species of Omphalina and related genera. Therefore, the results from phylogenetic analyses of this large molecular data set converged on one of the three most parsimonious topologies generated by the combined data set analysis. This topology was not recovered from either data set when analysed separately. This suggests that Rodrigo's homogeneity test might be better suited than the two other tests for determining if trees obtained from different data sets are sampling statistics of the same phylogenetic history. Key words: data sets heterogeneity, homogeneity test, lichen phylogeny, Omphalina, ribosomal DNA.


Phytotaxa ◽  
2019 ◽  
Vol 392 (1) ◽  
pp. 1
Author(s):  
GABRIEL F. GONÇALVES ◽  
ANNA VICTORIA S. R. MAUAD ◽  
GIULIANA TAQUES ◽  
ERIC C. SMIDT ◽  
FÁBIO DE BARROS

In order to evaluate the monophyly of the genus Orleanesia (Orchidaceae) and to assess its position within Laeliinae, a phylogenetic analysis was performed using molecular (nuclear ITS and plastid matK DNA sequences) and morphological data. A taxonomic revision of Orleanesia was also performed, with a description of the genus and its species using fresh living plants and 115 exsiccates from 31 herbaria. All phylogenetic analyses were highly congruent, and thus the sequence data from all three data sets were combined. The resulting phylogeny corroborated the monophyly of Orleanesia, with two strongly supported clades, and confirmed Caularthron as its sister group. Character analysis was not very informative due to a high degree of homoplasy. Two lectotypifications and three new synonyms were proposed for the genus, thereby reducing the number of accepted species to six. Although none of the species of Orleanesia are considered endangered, it is clear that some populations are threatened with deforestation and habitat reduction.


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