Phylogenetic relationships in the Mediterranean Helichrysum (Asteraceae, Gnaphalieae) based on nuclear rDNA ITS sequence data

2004 ◽  
Vol 17 (3) ◽  
pp. 241 ◽  
Author(s):  
M. Galbany-Casals ◽  
N. Garcia-Jacas ◽  
A. Susanna ◽  
L. Sáez ◽  
C. Benedí
Keyword(s):  
Sequence Data ◽  
Cladistic Analysis ◽  
Mediterranean Area ◽  
Internal Transcribed Spacers ◽  
Nuclear Rdna ◽  
Generic Delimitation ◽  
Rdna Its ◽  
The Mediterranean ◽  
Sectional Classification

The internal transcribed spacers ITS1 and ITS2 of the nuclear rDNA were sequenced for 41 Helichrysum species (Gnaphalieae), focusing on the Mediterranean group of species, together with eight representatives of other genera of the Gnaphalieae, in order to check the hypothesised monophyly of the Mediterranean Helichrysum group and the correspondence of the sequence data with its traditional sectional classification. The cladistic analysis of sequence data supports monophyly of the Mediterranean Helichrysum excluding H. frigidum and H. montelinasanum. The traditional classification of the Mediterranean species into two sections, Helichrysum and Virginea, is not supported, whereas a group constituted by species from the west Mediterranean area is shown as a moderately supported monophyletic clade in the strict consensus tree. Other results also show and confirm the complexity, still not satisfactorily resolved, of the Helichrysum generic delimitation: Pseudognaphalium luteoalbum appears merged in Helichrysum whereas Helichrysum dasyanthum appears more related to Anaxeton laeve than to any Helichrysum species.

Generic delimitations in the family Stictidaceae (Ostropales, Ascomycota): the Stictis–Conotrema problem

2005 ◽  
Vol 37 (1) ◽  
pp. 67-75 ◽  
Author(s):  
Mats WEDIN ◽  
Heidi DÖRING ◽  
Kristina KÖNBERG ◽  
Gunnar GILENSTAM
Keyword(s):  
Sequence Data ◽  
Sister Group ◽  
Lsu Rdna ◽  
Infrageneric Classification ◽  
Rdna Its ◽  
The Family ◽  
Rdna Sequence Data ◽  
Natural Groups ◽  
High Support

The family Stictidaceae (Ostropales, Ascomycota) contains both lichenized and non-lichenized fungi. Here, we test if Conotrema (lichenized) and Stictis (non-lichenized) as currently delimited are distinct monophyletic genera, by parsimony and parsimony jackknifing analyses of combined nuclear rDNA (ITS and partial LSU rDNA) and mitochondrial SSU rDNA sequence data matrices. The study includes four species of Stictis, three species of Conotrema, and representatives of the related Schizoxylon (lichenized), Odontotrema, Carestiella (at least sometimes associated with algae), Cryptodiscus and Thelotrema (lichenized). In all analyses, the Conotrema species were nested within Stictis with high support. Thus, we conclude that Conotrema are only lichenized representatives of Stictis. The type species of the two generic names, C. urceolatum and S. radiata, are sister taxa in our analyses. Furthermore, the analysis gave no support for the present infrageneric classification of Stictis. Carestiella socia (the type of Carestiella) and the two representatives of Schizoxylon studied were also nested within Stictis s. lat. The Odontotremataceae is the sister group to the Stictidaceae, and Cryptodiscus foveolaris groups with Thelotrema rather than with the Stictidaceae. We conclude that lichenization in the Stictidaceae does not characterize natural groups, and that Conotrema should be considered a synonym to Stictis, as predicted by anatomical characteristics. The new combinations Stictis urceolatum and Stictis populorum are made.

Generic delimitation and phylogenetic uncertainty: an example from a group that has undergone an explosive radiation

2005 ◽  
Vol 18 (1) ◽  
pp. 41 ◽  
Author(s):  
L. A. Orthia ◽  
L. G. Cook ◽  
M. D. Crisp
Keyword(s):  
Phylogenetic Trees ◽  
Evolutionary History ◽  
Sequence Data ◽  
Evolutionary Relationships ◽  
Recent Proposal ◽  
Generic Delimitation ◽  
Dna Sequence Data ◽  
Single Genus ◽  
Phylogeny Estimation

Phylogenetic trees can provide a stable basis for a higher-level classification of organisms that reflects evolutionary relationships. However, some lineages have a complex evolutionary history that involves explosive radiation or hybridisation. Such histories have become increasingly apparent with the use of DNA sequence data for phylogeny estimation and explain, in part, past difficulties in producing stable morphology-based classifications for some groups. We illustrate this situation by using the example of tribe Mirbelieae (Fabaceae), whose generic classification has been fraught for decades. In particular, we discuss a recent proposal to combine 19 of the 25 Mirbelieae genera into a single genus, Pultenaea sens. lat., and how we might find stable and consistent ways to squeeze something as complex as life into little boxes for our own convenience.

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.

Phylogenetic Relationships within Phacelia subgenus Phacelia (Hydrophyllaceae) Inferred From Nuclear rDNA ITS Sequence Data

2005 ◽  
Vol 30 (3) ◽  
pp. 627-634 ◽  
Author(s):  
Cynthia Gilbert ◽  
John Dempcy ◽  
Constance Ganong ◽  
Robert Patterson ◽  
Greg S. Spicer
Keyword(s):  
Phylogenetic Relationships ◽  
Sequence Data ◽  
Its Sequence ◽  
Nuclear Rdna ◽  
Rdna Its

The ‘Mediterranean’ Ramalina Panizzei North of the alps: Morphological, Chemical and rDNA Sequence Data

1997 ◽  
Vol 29 (5) ◽  
pp. 441-454 ◽  
Author(s):  
Urs Groner ◽  
Scott LaGreca
Keyword(s):  
Dna Sequence ◽  
Sequence Data ◽  
Taxonomic Revision ◽  
Distinct Species ◽  
Dna Sequence Data ◽  
Rdna Its ◽  
Rdna Sequence Data ◽  
The Alps ◽  
The Mediterranean ◽  
A Site

AbstractRamalina panizzei De Not. is reported from Switzerland and north of the Alps for the first time. Recent collections and thalli found amongst specimens of R. fastigiata (Pers.) Ach. are described; the species is obviously not restricted to the Mediterranean. The confusion in several herbaria around this and related corticolous species, particularly R. subgeniculata Nyl. and R. fastigiata, can be traced back to imprecise original and subsequent diagnoses, all of which lack a clear species delimitation. Similarities and differences of these species are discussed. In addition, sequences from the rDNA ITS regions were determined for two individuals of R. panizzei and two of R. fastigiata, including one of each from a site where both species grow intermixed. Kimura 2-parameter genetic-distance estimates indicate that R. panizzei and R. fastigiata are as different from each other as either is from the reference species R. siliquosa (Hudson) A. L. Sm. s.l. A broad-based taxonomic revision of involved species is not possible due to the limited number of analyses, but the results demonstrate the potential for using DNA sequence data to investigate species-level questions in lichens. Based on morphology, chemistry, and DNA sequence data, R. panizzei is retained as a distinct species.

Nuclear rDNA ITS sequence variation in the trematode genus Echinostoma: an aid to establishing relationships within the 37-collar-spine group

Parasitology ◽  
1995 ◽  
Vol 111 (5) ◽  
pp. 609-615 ◽  
Author(s):  
J. A. T. Morgan ◽  
D. Blair
Keyword(s):  
Sequence Data ◽  
Distinct Group ◽  
Nominal Species ◽  
Nuclear Rdna ◽  
Dna Sequence Data ◽  
Collar Spine ◽  
Rdna Its ◽  
History Of ◽  
Trematode Genus ◽  
Future Work

SUMMARYThe taxonomic history of members of the 37-collar-spine group within the genus Echinostoma has been very confused. We obtained DNA sequence data from the nuclear rDNA ITS1, 5·8S and ITS2 of 7 nominal species belonging to this group, Echinostoma trivolvis (Cort, 1914), E. revolution (Frölich, 1802), E. caproni Richard, 1964, E. liei Jeyarasasingam et al. 1972, E. paraensei Lie & Basch, 1967, two African isolates, E. sp.I and E. sp.II, and of one 28-collar-spined echinostome, E. hortense (Asada, 1926). Five of the eight species were clearly distinguishable using ITS data. Sequences from the remaining three taxa, E. caproni, E. sp.II and E. liei were identical to one another and the group containing these taxa was distant from other 37-collar-spine species on a phylogenetic tree. E. trivolvis and E. paraensei form a second, but less distinct group within the 37-collar-spine group. The resolution obtained using DNA sequencing will assist in the current reclassification of the group. It also provides a model for future work on sibling species.

Nuclear rDNA ITS sequence data used to construct the first phylogeny of Vanguerieae (Rubiaceae)

2002 ◽  
Vol 230 (3-4) ◽  
pp. 173-187 ◽  
Author(s):  
H. Lantz ◽  
K. Andreasen ◽  
B. Bremer
Keyword(s):  
Sequence Data ◽  
Its Sequence ◽  
Nuclear Rdna ◽  
Rdna Its
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