Search results for "Polyphyly"
showing 10 items of 39 documents
Nuclear rDNA ITS-2 sequences reveal polyphyly of Panstrongylus species (Hemiptera: Reduviidae: Triatominae), vectors of Trypanosoma cruzi1
2002
Panstrongylus species are widely distributed throughout the Americas, where they act as vectors of Trypanosoma cruzi, agent of Chagas disease. Their intraspecific relationships, taxonomic position and phylogeny in relation to other Triatomini were explored using ribosomal DNA (rDNA) internal transcribed spacer 2 (ITS-2) sequence polymorphisms and maximum parsimony, distance and maximum likelihood analyses of 10 populations representing six species of the genus (P. megistus, P. geniculatus, P. rufotuberculatus, P. lignarius, P. herreri and P. chinai). At the subspecific level, P. megistus appeared more homogeneous than P. rufotuberculatus and P. geniculatus (both with broader distribution). …
Eukaryotes Are a Holophyletic Group of Polyphyletic Origin.
2020
Because of the polyphyletic origin of the eukaryotic monophylum, eukaryogenesis within prokaryotes is not comparable with mammal origin within paraphyletic reptiles. Both synapomorphies and plesiomorphies represent apomorphies and are indeed suitable for defining monophyletic (holophyletic and paraphyletic) groups. Alphaproteobacteria (Bacteria) and Asgard (Archaea) are the ancestors of LECA (the Last Eukaryotic Common Ancestor). The presence of ESPs in Asgard does not dispute the polyphyletic origin of eukaryotes ; it only further corroborates it. “Candidatus Prometheoarchaeum syntrophicum” is the closest relative to eukaryotes and the only Asgard with available microscopy data. This newly…
Hidden Mediterranean diversity: Assessing species taxa by molecular phylogeny within the opilionid family Trogulidae (Arachnida, Opiliones)
2009
This is the first comprehensive study to evaluate the relationships between the western palearctic harvestman families Dicranolasmatidae, Trogulidae and Nemastomatidae with focus on the phylogeny and systematics of Trogulidae, using combined sequence data of the nuclear 28S rRNA and the mitochondrial cytochrome b gene. Bayesian analysis and Maximum parsimony do not reliably resolve Dicranolasma as distinct family but place it on a similar phylogenetic level as several lineages of Trogulidae. Nemastomatidae and Trogulidae turned out to be monophyletic, as did genera Anelasmocephalus and Trogulus within the Trogulidae. The genera Calathocratus, Platybessobius and Trogulocratus each appeared p…
A critical comment on ‘ankyroids’ (Echinodermata, Stylophora)
2001
Abstract A recent cladistic analysis of stylophoran echinoderms performed by Parsley suggested that mitrates are polyphyletic and derived from symmetrical cornutes. Parsley erected the order Ankyroida to include all derived cornutes and mitrates. The present paper addresses several significant problems in the data matrix of Parsley's cladistic analysis. Detailed morphological comparisons of various stylophorans suggest that important homologies have been ignored: cornute zygal crest and mitrate septum, adorals, glossal and digital. Subanals are not homologous in mitrates. Identification of plate homologies shows that similar-looking symmetrical thecal outlines have been acquired independent…
Molecular phylogeny of the Old World representatives of Papaveraceae subfamily Papaveroideae with special emphasis on the genus Meconopsis
1995
The RFLP-analysis of PCR amplified cpDNA fragments of 42 representatives of Papaveraceae subfam. Papaveroideae resulted in six most parsimonious cladograms. The subfamily can be divided into a New World group (Arctomecon, Argentone, Canbya, Romneya and Platystemon) and an Old World group (Meconopsis, Papaver s.l. and Roemeria) containing Stylomecon heterophylla and Papaver californicum as New World taxa. In the Old World group neither Meconopsis nor Papaver are monophyletic. Whereas Meconopsis consists of three clades, Papaver comprises five clades, with Roemeria as sister group to P. sect. Argemonidium and Stylomecon as sister group to P. californicum. Various lines of evidence suggest tha…
The phylogeny of (Gentianaceae) and its colonization of the southern hemisphere as revealed by nuclear and chloroplast DNA sequence variation
2001
Abstract The generic circumscription and infrageneric phylogeny of Gentianella was analysed based on matK and ITS sequence variation. Our results suggested that Gentianella is polyphyletic and should be limited to species with only one nectary per petal lobe. Gentianella in such a circumscription is most closely related to one part of a highly polyphyletic Swertia. within uninectariate Gentianella two major groups could be recognized: 1) northern hemispheric species with vascularized fimbriae at the base of the corolla lobes, and 2) northern hemispheric, South American, and Austrlia/New Zealand species without vascularized fimbriae. When fimbriae are present in this latter group, they are n…
The phylogeny ofPapaver s. l. (Papaveraceae): Polyphyly or monophyly?
1997
An RFLP analysis of the chloroplast genetrnK of 32 species of the generaPapaver, Roemeria, Stylomecon, andMeconopsis leads to the following conclusions: (1) AsianMeconopsis consists of two distinct clades and is paraphyletic in relation toPapaver, Roemeria, Stylomecon, and the W EuropeanMeconopsis cambrica. (2) Sister group relationships ofRoemeria toPapaver sect.Argemonidium and ofStylomecon toPapaver californicum are well-supported. (3)Meconopsis cambrica is nested withinPapaver (incl.Roemeria andStylomecon). The consideration of morphology, geographical distribution and ecology leads to the conclusion thatM. cambrica is best regarded as a member ofMeconopsis, and thatPapaver arose polyph…
Molecular phylogeny of the freshwater sponges in Lake Baikal
2003
The phylogenetic relationship of the freshwater sponges (Porifera) in Lake Baikal is not well understood. A polyphyletic and/or monophyletic origin have been proposed. The (endemic) Baikalian sponges have been subdivided into two families: endemic Lubomirskiidae and cosmopolitan Spongillidae. In the present study, two new approaches have been made to resolve the phylogenetic relationship of Baikalian sponges; analysis of (1) nucleotide sequences from one mitochondrial gene, the cytochrome oxidase subunit I (COI) and of (2) one selected intron from the tubulin gene. Specimens from the following endemic Baikalian sponge species have been studied; Lubomirskia baicalensis, Baikalospongia interm…
Molecular phylogeny of Metazoa (animals): monophyletic origin.
1995
The phylogenetic relationships within the kingdom Animalia (Metazoa) have long been questioned. Focusing on the lowest eukaryotic multicellular organisms, the metazoan phylum Porifera (sponges), it remained unsolved if they evolved multicellularity independently from a separate protist lineage (polyphyly of animals) of derived from the same protist group as the other animal phyla (monophyly). After having analyzed genes typical for multicellularity (adhesion molecules/receptors and a nuclear receptor), we present evidence that Porifera should be placed in the kingdom Animalia. We therefore suggest a monophyletic origin for all animals.
Kali dodecanesicum (Chenopodiaceae, Salsoloideae) a new species from Greece
2015
Kali dodecanesicum, a new species from some islands (i.e. Rhodes, Kos and Nisyros) of the Dodecanese in the south-eastern Aegean (Greece), is described and illustrated. According to recent literature, Kali is treated as a distinct genus from the polyphyletic Salsola s.l., which includes several annual species. The new species is morphologically well separated from the other Kali taxa mainly for the shape of the fruiting perianth, showing closer relationships with Kali ponticum. Its ecological requirements, distribution, and conservation status are also examined, together with an analytic key of the Kali species occurring in the Mediterranean area.