Diatoms are crucially important to the global ecosystem due to their role in regulating the world’s carbon and silicon cycles, and their production of large amounts of organic material in aquatic environments. They are thought to comprise ca. 100,000 species, although some estimates suggest that there could be over a million. Despite their importance and high species diversity, little is known about their phylogeny due to technical issues that hinder the reconstruction of their relationships. However, owing to a new technique that allows for DNA to be amplified from a single isolated cell, it is possible to explore diatom relationships with extensive taxonomic sampling. This thesis aims to demonstrate that the integration of molecular data and morphological characters can provide a new paradigm for future phylogenetic and taxonomic studies of diatoms, especially among closely related and taxonomically complex groups. To achieve this, I examined common species from two naviculoid diatom genera, Frustulia and Navicula using sequence data from three molecular markers (rbcL, atpB, 18S), traditional and fine-scale morphological characters, and frustule shape. The molecular markers rbcL and atpB evolved at a similar rate and performed well at reconstructing species-level phylogenies, whereas 18S was more conserved and best used for resolving relationships at higher taxonomic levels. Hidden diversity was uncovered in what have traditionally been thought as well-circumscribed taxa, and three new species were described. The methods used here show promise for the future of diatom systematics.

The phylogenetic placement of the phylum Tardigrada among the Metazoa is somewhat uncertain. In analyses based on morphological characters, tardigrades are usually associated with arthropods but tardigrades have also been associated with a number of aschelminth phyla. We have sequenced the nearly complete 18S rRNA gene from a eutardigrade. Neighbor-Joining and Maximum-Parsimony analyses place tardigrades in a clade that includes arthropods and priapulids, but not other aschelminths.

O filo Myxozoa compreende organismos parasitários que infectam vertebrados, principalmente peixes, em diversas regiões do Brasil e do mundo. Com mais de 2180 espécies já descritas os mixosporídeos estão entre os patógenos mais importantes que infectam peixes tanto de ambiente natural como de sistemas de criação. Neste estudo, foram realizadas coletas no ano de 2012, onde foram capturados 13 espécimes de piraputanga (Brycon hilarii) e 14 espécimes de piauçu (Leporinus macrocephalus) oriundos de pisciculturas do estado de São Paulo. Foram encontrados mixosporídeos infectando o rim de B. hilarii e o filamento branquial de L. macrocephalus. Para a identificação das espécies de parasitos, foi utilizada a microscopia de luz para a análise morfológica e, também, histopatológica para a observação das alterações decorrentes do parasitismo. A análise ultraestrutural foi realizada para verificar a interação parasita-hospedeiro do mixosporídeo encontrado na piraputanga. A análise filogenética do gene 18S rDNA avaliou a relação entre as espécies identificadas com outras espécies de mixosporídeos já descritas. Uma nova espécie de Myxobolus foi descrita neste estudo infectando o rim de B. hilarii e a caracterização molecular e filogenética de Henneguya leporinicola, encontrado infectando o filamento branquial de L. macrocephalus, foi realizada. No estudo filogenético, utilizando o método de Máxima Verossimilhança para ambas as espécies, verificou-se que as espécies de mixosporídeos se agruparam primeiro de acordo com a ordem do hospedeiro Characiforme e pelo tropismo tecidual. A análise molecular demonstrou diferenças genéticas significativas em comparação com outras espécies já descritas na América do Sul e em outros países. / The Myxozoa phylum comprises parasitic organisms that infect vertebrates, mainly fish, in many areas from Brazil and from the world. With more than 2180 species already described, myxosporeans are among the most important fish pathogens which infect both natural environment and breeding systems. In this study, captures were made in 2012, where 13 specimens of piraputanga (Brycon hilarii) and 14 specimens of piauçu (Leporinus macrocephalus) proceeding from fish farms in the state of Sao Paulo were capured. Myxosporeans were found infecting the kidney of B. hilarii and the gill filament of L. Macrocephalus. For the identification of parasite species, it was used light microscopy for morphological and histopathological analyzes to observe the damage caused by parasitism. The ultrastructural analysis was performed to verify the host-parasite myxosporean interaction found on piraputanga. The phylogenetic analysis of 18S rDNA evaluated the relation between the species identified with other myxosporean species already described. A new Myxobolus species was described in this study infecting the kidney of B. hilarii and molecular characterization and phylogenetic of Henneguya leporinicola, infecting the gill filament of L. macrocephalus, was performed. In phylogenetic study, using the method of Maximum Likelihood for both species, it was observed that the species of myxosporean grouped according to the order of the host Characiform and the tissue tropism. Molecular analysis showed significant genetic differences with other described species in South America and other countries.

Os organismos do filo Myxozoa são endoparasitas obrigatórios que infectam principalmente peixes em diversas regiões do mundo, estando entre os mais importantes patógenos de peixes, com mais de 2180 espécies descritas porém, pouco se conhece deste parasita em peixes do Brasil. Neste estudo foram realizadas coletas entre abril de 2011 a agosto de 2012, onde foram coletados oito exemplares de piapara (Leporinus obtusidens) e dezessete exemplares de dourado (Salminus brasiliensis), oriundos do rio Mogi-Guaçu, próximo a Cachoeira de Emas, localizada no município de Pirassununga, estado de São Paulo. As análises morfológicas (microscopia de luz, histologia e a análise ultraestrutural), técnicas de biologia molecular (PCR e sequenciamento) foram utilizadas na identificação de duas novas espécies de Henneguya e análise filogenética do gene 18S rDNA foi realizada para avaliar a relação filogenética desta duas novas espécies com outras espécies de mixosporídeos. Duas novas espécies foram encontradas neste estudo. Uma delas foi encontrada infectando a nadadeira de L. obtusidens e é descrita neste estudo como Henneguya sp. 1 e uma outra espécie encontrada infectando a membrana do arco da branquial e na membrana entre os raios da nadadeira de S. brasiliensis, a qual foi aqui descrita como Henneguya sp. 2. A análise histopatológica revelou que Henneguya sp. 1 ocasionou uma leve compressão no tecido adjacente. A análise ultra-estrutural permitiu a compreensão da interface parasita-hospedeiro e o processo de esporogênese das duas espécies descritas; além disso, foi observado a presença de vesículas esbranquiçadas para Henneguya sp. 2, com função ainda desconhecida. Nos estudos filogenéticos, utilizando os métodos máxima parcimônia e máxima verossimilhança para ambas as espécies, foi avaliado no estudo 1 que Henneguya sp. 1, parasita de peixe characiforme, aparece isolado dando origem a um clado irmão de Henneguya spp., parasitas de siluriformes, characifomes e esociformes; já no estudo 2, a análise filogenética da espécie Henneguya sp. 2, também parasita de peixe characiforme, foi observado a formação de um clado com 3 espécies parasitas de characiformes, sendo duas espécies de Henneguya descritas neste estudo e o Myxobolus oliveirai. / The parasites of Myxozoa are endoparasites that infect mainly fishes in several parts of the world, being this group considered one of the most important pathogens of fishes, with more than 2180 species described. However little is known about this group of parasite in Brazil. During this study, eight piapara (Leporinus obtusidens) and seventeen dourado (Salminus brasiliensis) were caught in Mogi-Guaçu river in a period from April 2011 to August 2012, near waterfall Cachoeira de Emas located at Pirassununga city, state of São Paulo, Brazil. Morphological analyses (light microscopy, histology and ultrastructure) and molecular biology techniques (PCR and sequencing) where done to identify two new species of Henneguya and phylogenetic analyses using the 18S rDNA gene were performed to evaluate the phylogenetic relationship of this two new species among others myxosporeans available on GenBank. Henneguya sp. 1 has been described infecting the fin of L. obtusidens and Henneguya sp. 2 has been described infecting the gill arch membrane and the fin membrane of S. brasiliensis. The histopathological analyses revealed that Henneguya sp. 1 occasioned a small compression of adjacent tissue of the host. Ultraestructural analyses showed the host-parasite\'s interface and the sporogenesis of the two Henneguya spp. furthermore Henneguya sp. 2 showed several whitish vesicles with an unknown function. Phylogenetic studies using the maximum parsimony and maximum likelihood methods, showed in the first study Henneguya sp .1 appearing alone as a basal branch of a sister clade composed by Henneguya parasites of siluriforms, characiforms and esociforms fishes, and the second study showed Henneguya sp. 2 grouped with Hennegua sp. 1 and Myxobolus oliveirai, both parasites of characiforms fishes.

Šunų babeziozė – tai liga, greitai plintanti visame pasaulyje, kurią sukelia pirmuonys, priklausantys Babesia genčiai. Ligos sukėlėjus platina Dermocentor, Rhipicephalus, Haemaphysalis genties erkės. Lietuvoje paplitę Dermacentor reticulatus erkės - pagrindiniai Babesia canis vektoriai. B. canis patenka į raudonąsias kraujo ląsteles (eritrocitus) ir jas suardo. Kasmet sergamumas šunų babezioze visoje Europoje bei Lietuvoje stipriai auga. Darbo tikslas buvo įvertinti šunų užsikrėtimą Babesia canis patogenais ir identifikuoti Babesia canis porūšius ir padermes, panaudojant molekulinius tyrimo metodus ir filogenetinę sekų analizę. Šiame darbe buvo tiriami 20 šunų, sergančių babezioze,( pagal babeziozei būdingą klinikinę išraišką) kraujo mėginiai, kurie buvo surinkti iš Kauno apskrities Veterinarijos klinikų. Taikant molekulinį PGR (polimerazės grandininės reakcijos) metodą, 17 iš šių mėginių buvo identifikuota Babesia canis canis. Atlikus palyginamąją Babesia canis canis 18S rRNR geno sekų analizę, pasitelkus Gen Bank duomenis, buvo nustatyta, kad Lietuvoje sekvenuotos sekos nuo užsikrėtusių šunų buvo identiškos tarpusavyje ir turėjo 91-100% panašumą su sekomis, identifikuotomis sergančiuose šunyse ir D. reticulatus erkėse kitose Europos šalyse. Identifikuotos sekos priklausė vienam iš genotipų, paplitusių Europoje, kuris pasižymi didesniu virulentiškumu. Europos šalyse nustatyta 10 B. canis canis sekų variantų, identifikuotų pagal 18S rRNR geno sekų analizę. / Canine babesiosis is a disease, quickly spreading worldwide, which is caused by the protozoa belonging to the genus Babesia. The disease agents are transmitted by ticks of the genera Dermocentor, Rhipicephalus, and Haemaphysalis. Dermacentor reticulatus ticks, which are widely spread in Lithuania, are the main vectors of Babesia canis. B. canis infects red blood cells (erythrocytes) and destroys them. Every year the morbidity of Babesia canis is intensely growing in the whole of Europe and Lithuania. The aim of thesis was to evaluate the canine infection with Babesia canis pathogens and identify species and subspecies of Babesia canis, using molecular methods of analysis and phylogenetic sequence. The research focused on 20 dogs infected with Babesia canis (in accordance with the clinical expression characteristic of babesiosis); the blood samples were collected in the veterinary clinics in the Kaunas region. Applying the molecular PCR (Polymerase chain reaction) method, 17 of the samples were identified as cases of Babesia canis canis. On the basis of the contrastive gene sequencing analysis of Babesia canis canis 18S rRNR and the data of Gen Bank it was determined that in Lithuania the sequential sequences of infected dogs were identical and by 91-100 percent resembled the sequences identified in infected dogs and D. reticulatus ticks in other European countries. The identified sequences belonged to one of the genotypes which is widely spread in Europe and is... [to full text]

Os organismos do filo Myxozoa são endoparasitas obrigatórios que infectam principalmente peixes em diversas regiões do mundo, estando entre os mais importantes patógenos de peixes, com mais de 2180 espécies descritas porém, pouco se conhece deste parasita em peixes do Brasil. Neste estudo foram realizadas coletas entre abril de 2011 a agosto de 2012, onde foram coletados oito exemplares de piapara (Leporinus obtusidens) e dezessete exemplares de dourado (Salminus brasiliensis), oriundos do rio Mogi-Guaçu, próximo a Cachoeira de Emas, localizada no município de Pirassununga, estado de São Paulo. As análises morfológicas (microscopia de luz, histologia e a análise ultraestrutural), técnicas de biologia molecular (PCR e sequenciamento) foram utilizadas na identificação de duas novas espécies de Henneguya e análise filogenética do gene 18S rDNA foi realizada para avaliar a relação filogenética desta duas novas espécies com outras espécies de mixosporídeos. Duas novas espécies foram encontradas neste estudo. Uma delas foi encontrada infectando a nadadeira de L. obtusidens e é descrita neste estudo como Henneguya sp. 1 e uma outra espécie encontrada infectando a membrana do arco da branquial e na membrana entre os raios da nadadeira de S. brasiliensis, a qual foi aqui descrita como Henneguya sp. 2. A análise histopatológica revelou que Henneguya sp. 1 ocasionou uma leve compressão no tecido adjacente. A análise ultra-estrutural permitiu a compreensão da interface parasita-hospedeiro e o processo de esporogênese das duas espécies descritas; além disso, foi observado a presença de vesículas esbranquiçadas para Henneguya sp. 2, com função ainda desconhecida. Nos estudos filogenéticos, utilizando os métodos máxima parcimônia e máxima verossimilhança para ambas as espécies, foi avaliado no estudo 1 que Henneguya sp. 1, parasita de peixe characiforme, aparece isolado dando origem a um clado irmão de Henneguya spp., parasitas de siluriformes, characifomes e esociformes; já no estudo 2, a análise filogenética da espécie Henneguya sp. 2, também parasita de peixe characiforme, foi observado a formação de um clado com 3 espécies parasitas de characiformes, sendo duas espécies de Henneguya descritas neste estudo e o Myxobolus oliveirai. / The parasites of Myxozoa are endoparasites that infect mainly fishes in several parts of the world, being this group considered one of the most important pathogens of fishes, with more than 2180 species described. However little is known about this group of parasite in Brazil. During this study, eight piapara (Leporinus obtusidens) and seventeen dourado (Salminus brasiliensis) were caught in Mogi-Guaçu river in a period from April 2011 to August 2012, near waterfall Cachoeira de Emas located at Pirassununga city, state of São Paulo, Brazil. Morphological analyses (light microscopy, histology and ultrastructure) and molecular biology techniques (PCR and sequencing) where done to identify two new species of Henneguya and phylogenetic analyses using the 18S rDNA gene were performed to evaluate the phylogenetic relationship of this two new species among others myxosporeans available on GenBank. Henneguya sp. 1 has been described infecting the fin of L. obtusidens and Henneguya sp. 2 has been described infecting the gill arch membrane and the fin membrane of S. brasiliensis. The histopathological analyses revealed that Henneguya sp. 1 occasioned a small compression of adjacent tissue of the host. Ultraestructural analyses showed the host-parasite\'s interface and the sporogenesis of the two Henneguya spp. furthermore Henneguya sp. 2 showed several whitish vesicles with an unknown function. Phylogenetic studies using the maximum parsimony and maximum likelihood methods, showed in the first study Henneguya sp .1 appearing alone as a basal branch of a sister clade composed by Henneguya parasites of siluriforms, characiforms and esociforms fishes, and the second study showed Henneguya sp. 2 grouped with Hennegua sp. 1 and Myxobolus oliveirai, both parasites of characiforms fishes.

O filo Myxozoa compreende organismos parasitários que infectam vertebrados, principalmente peixes, em diversas regiões do Brasil e do mundo. Com mais de 2180 espécies já descritas os mixosporídeos estão entre os patógenos mais importantes que infectam peixes tanto de ambiente natural como de sistemas de criação. Neste estudo, foram realizadas coletas no ano de 2012, onde foram capturados 13 espécimes de piraputanga (Brycon hilarii) e 14 espécimes de piauçu (Leporinus macrocephalus) oriundos de pisciculturas do estado de São Paulo. Foram encontrados mixosporídeos infectando o rim de B. hilarii e o filamento branquial de L. macrocephalus. Para a identificação das espécies de parasitos, foi utilizada a microscopia de luz para a análise morfológica e, também, histopatológica para a observação das alterações decorrentes do parasitismo. A análise ultraestrutural foi realizada para verificar a interação parasita-hospedeiro do mixosporídeo encontrado na piraputanga. A análise filogenética do gene 18S rDNA avaliou a relação entre as espécies identificadas com outras espécies de mixosporídeos já descritas. Uma nova espécie de Myxobolus foi descrita neste estudo infectando o rim de B. hilarii e a caracterização molecular e filogenética de Henneguya leporinicola, encontrado infectando o filamento branquial de L. macrocephalus, foi realizada. No estudo filogenético, utilizando o método de Máxima Verossimilhança para ambas as espécies, verificou-se que as espécies de mixosporídeos se agruparam primeiro de acordo com a ordem do hospedeiro Characiforme e pelo tropismo tecidual. A análise molecular demonstrou diferenças genéticas significativas em comparação com outras espécies já descritas na América do Sul e em outros países. / The Myxozoa phylum comprises parasitic organisms that infect vertebrates, mainly fish, in many areas from Brazil and from the world. With more than 2180 species already described, myxosporeans are among the most important fish pathogens which infect both natural environment and breeding systems. In this study, captures were made in 2012, where 13 specimens of piraputanga (Brycon hilarii) and 14 specimens of piauçu (Leporinus macrocephalus) proceeding from fish farms in the state of Sao Paulo were capured. Myxosporeans were found infecting the kidney of B. hilarii and the gill filament of L. Macrocephalus. For the identification of parasite species, it was used light microscopy for morphological and histopathological analyzes to observe the damage caused by parasitism. The ultrastructural analysis was performed to verify the host-parasite myxosporean interaction found on piraputanga. The phylogenetic analysis of 18S rDNA evaluated the relation between the species identified with other myxosporean species already described. A new Myxobolus species was described in this study infecting the kidney of B. hilarii and molecular characterization and phylogenetic of Henneguya leporinicola, infecting the gill filament of L. macrocephalus, was performed. In phylogenetic study, using the method of Maximum Likelihood for both species, it was observed that the species of myxosporean grouped according to the order of the host Characiform and the tissue tropism. Molecular analysis showed significant genetic differences with other described species in South America and other countries.

This master's thesis is focused on cytogenetic analysis and karyotype variability of the Nemastomatidae family. This family comprises morphologically uniform harvestmen of small sizes, with low mobility, and with center of distribution in Europe. Karyotype differences could play an important role for detection of cryptic diversity in this family. The karyotype analysis is focused mainly on Alpine and Pyrenean endemic species but also on other taxons located in Central Europe. The goal was not only to identify the differences which occur between the specific genera and species, but also eventually between populations. For detection of the specific chromosomal alterations in evolution of the karyotype in Nemastomatidae the fluorescent in situ hybridization (FISH) was used, localizing the positions and amounts of gene clusters for 18S rRNA. From the results we can assume that the number of chromosomes in the family Nemastomatidae can range between 2n = 12- 30. Further it was found out that in Nemastomatidae the biarmed chromosomes are more prevalent, and that the species which have lower amounts of chromosomes contain chromosomes that noticeably differ in size (probably because of chromosomal fusions). These results indicate that with some morphologically uniform species, the knowledge of specific...

A character data set suitable for cladistic analysis of tardigrades at the family level was developed. The data matrix consisted of 50 morphological characters from 15 families of tardigrades and was analyzed by maximum parsimony. Kinorhynchs, loriciferans and gastrotrichs were used as outgroups. The results agree with the currently accepted hypothesis that Eutardigrada and Heterotardigrada are distinct monophyletic groups. Among the eutardigrades, Eoyhypsibiidae was found to be a sister group to Macrobiotidae + Hypsibiidae, while Milnesiidae was the basal eutardigrade family. The basal heterotardigrade family was found to be Oreellidae. Echiniscoideans grouped with some traditional Arthrotardigrada (Renaudarctidae, Coronarctidae + Batillipedidae) suggesting that the arthrotardigrades are not monophyletic. An 18S rRNA phylogenetic hypothesis was developed and supports the monophyly of Heterotardigrada and of Parachela versus Apochela within the Eutardigrada. Mapping of habitat preference suggest that terrestrial tardigrades are the ancestral state. Molecular analysis of a sediment sample with an unusually large population of tardigrades had a higher diversity when compared to manual sorting and counting.

SANTRAUKA PAUKŠČIUOSE APTINKAMŲ NEAPIBŪDINTŲ SARCOCYSTIS GENTIES RŪŠIŲ FILOGENETINIŲ RYŠIŲ TYRIMAS NAUDOJANT DALINES 18S IR 28S rRNR GENŲ SEKAS Petras Prakas Vilniaus Universiteto Ekologijos Institutas, Populiacinės Genetikos Laboratorija, Vilnius, Lietuva. Pagal cistų morfologiją, baltakaktėje žąsyje (Anser albifrons) aptiktos I tipo sarkocistos, didžiojoje antyje (Anas platyrhynchos) rastos II tipo sarkocistos, dviejose baltakaktėse žąsyse ir pilkojoje žąsyje (Anser anser) nustatytos III tipo sarkocistos, varnoje (Corvus cornix) identifikuotos V tipo sarkocistos. Iš paukščių, kaip tarpinių šeimininkų išskirtos sarkosporidijos aprašomos pirmą kartą bei yra neįvardintos rūšys. Baltakaktėje bei pilkojoje žąsyse išskirtos III tipo sarkocistos gali būti tos pačios sarkocistų rūšies parazitavimo skirtingų rūšių tarpiniuose šeimininkuose atvejis. Nustatytos 18S ir 28S rDNR fragmentų sekos pasižymėjo didžiausia homologija Sarcocystis bei Frenkelia gentims. Filogenetinių ryšių medyje sugrupuojamos šiame darbe tiriamos rūšys su Frenkelia microti, Frenkelia glareoli, Sarcocystis muris, Sarcocystis neurona. Rezultatai atskleidė Sarcocystis genties rūšių koevoliuciją su jų galutiniais šeimininkais. Remiantis tyrimo duomenimis, galima teigti, kad Sarcocystidae šeimos filogenetinius ryšius apsprendžia sarkosporidijų gyvybinio ciklo ypatybės, šeimininkų spektras bei parazitų specifiškumas šeimininkui. 18S ir 28S rRNR genų dalinių sekų analizė atskleidžia tirtų Sarcocystis sp. rūšių... [toliau žr. visą tekstą] / SUMMARY INVESTIGATION OF THE PHYLOGENETIC RELATIONSHIPS OF SARCOCYSTIS SPP. FOUND IN BIRDS USING 18S AND 28S rRNA GENE PARTIAL SEQENCES Petras Prakas Institute of Ecology of Vilnius University, Laboratory of Population Genetics, Vilnius, Lithuania Based on cyst morphology, Sarcocystis cysts type I were found in white-fronted goose (Anser albifrons), cysts type II in mallard (Anas platyrhynchos), cyst type III in one grey-lag goose (Anser anser) and two white-fronted geese, cyst type V in hooded crow (Corvus cornix). The sarcocysts isolated from the infected birds as intermediate host have not been previously described and are unnamed. Type III sarcocysts detected in white-fronted and greylag geese may illustrate the case of polyhostal nature of sarcocysts when the same-species parasites infesting intermediate hosts of different species. The obtained 18S and 28S ribosomal RNA partial gene sequences showed the highest homology for the genera Sarcocystis and Frenkelia. In the tree of phylogenetic relationships, the species involved in this study were grouped with Frenkelia microti, Frenkelia glareoli, Sarcocystis muris and Sarcocystis neurona. Results show co-evolution of Sarcocystis spp. with the final host. Based on data obtained it could be stated that phylogenetic relationships of Sarcocystidae family are influenced by peculiarity of life cycle, hosts spectrum and host specificity. Analysis of the partial sequences of 18S and 28S ribosomal RNA revealed the phylogenetic and... [to full text]