Orientador: Rodney Kozlowiski de Azevedo / Resumo: Os parasitos do filo Myxozoa são endoparasitas obrigatórios que infectam peixes, anfíbios, répteis, mamíferos, aves aquáticas em diversas regiões do mundo, com mais de 2180 espécies descritas, estando entre os mais importantes patógenos de peixes, porém, pouco se conhece deste parasito em peixes do Brasil. Neste estudo foram realizadas coletas entre março e setembro de 2016, na qual foram coletados 30 exemplares de curimba (Prochilodus lineatus) e dezessete exemplares de lambari (Astyanax altiaparanae), oriundos do rio Batalha, em dois locais de coleta, um ponto de coleta no município de Reginópolis e outro ponto no município de Agudos, estado de São Paulo. Foram utilizadas análises morfológicas (microscopia de luz, histologia e análise ultraestrutural), técnicas de biologia molecular (PCR e sequenciamento) na descrição de duas espécies de Henneguya Duas espécies foram documentadas neste estudo, uma delas foi encontrada infectando o filamento primário da brânquia de P. lineatus e é descrita neste estudo como Henneguya prochilodus e outra espécie encontrada infectando o filamento secundário da brânquia de A. altiparanae, a qual foi proposto uma descrição expandida da Henneguya chydadea Barassa et al. (2003), previamente descrita utilizando análises morfológicas e histopatologia. Análise filogenética do gene 18S rDNA foi realizada para avaliar a relação filogenética dessas duas espécies de Henneguya com outras espécies de mixosporídeos da América do Sul e de outras regiões do m... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Myxozoa parasites are obligate endoparasites that infect fish, amphibians, reptiles, mammals, waterfowl in several regions of the world, with more than 2180 described species, being among the most important fish pathogens, but little is known of this parasite in fish from Brazil. In this study were collected from March to September 2016, where 30 specimens of Curimba (Prochilodus lineatus) and seventeen specimens of lambari (Astyanax altiaparanae) from the Batalha River, in two collection sites, a collection point in the municipality of Reginópolis and another point in the municipality of Agudos, state of São Paulo. Morphological analyzes (light microscopy, histology and ultrastructural analysis), molecular biology techniques (PCR and sequencing) were used to describe two species of Henneguya. Two species were documented in this study, one of which was found infecting the primary filament of the gill of P. lineatus and is described in this study as Henneguya prochilodus and another species found infecting the secondary filament of the gill of A. altiparanae, which has been proposed an expanded description of Henneguya chydadea Barassa et al. (2003), previously described using morphological analysis and histopathology. Phylogenetic analysis of the 18S rDNA gene was performed to evaluate the phylogenetic relationship of these two species of Henneguya with other species of myxosporids from South America and other regions of the world. / Mestre

Submitted by Vinicius Panciera Tagliavini (viniciustagliavini@gmail.com) on 2018-04-21T17:38:50Z No. of bitstreams: 1 Dissertação Vinícius Panciera Tagliavini.pdf: 3064208 bytes, checksum: 4c9144ee7408032982fc3216adac6c5a (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2018-04-23T17:37:37Z (GMT) No. of bitstreams: 1 tagliavini_vp_me_bot.pdf: 3064208 bytes, checksum: 4c9144ee7408032982fc3216adac6c5a (MD5) / Made available in DSpace on 2018-04-23T17:37:37Z (GMT). No. of bitstreams: 1 tagliavini_vp_me_bot.pdf: 3064208 bytes, checksum: 4c9144ee7408032982fc3216adac6c5a (MD5) Previous issue date: 2018-02-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os parasitos do filo Myxozoa são endoparasitas obrigatórios que infectam peixes, anfíbios, répteis, mamíferos, aves aquáticas em diversas regiões do mundo, com mais de 2180 espécies descritas, estando entre os mais importantes patógenos de peixes, porém, pouco se conhece deste parasito em peixes do Brasil. Neste estudo foram realizadas coletas entre março e setembro de 2016, na qual foram coletados 30 exemplares de curimba (Prochilodus lineatus) e dezessete exemplares de lambari (Astyanax altiaparanae), oriundos do rio Batalha, em dois locais de coleta, um ponto de coleta no município de Reginópolis e outro ponto no município de Agudos, estado de São Paulo. Foram utilizadas análises morfológicas (microscopia de luz, histologia e análise ultraestrutural), técnicas de biologia molecular (PCR e sequenciamento) na descrição de duas espécies de Henneguya Duas espécies foram documentadas neste estudo, uma delas foi encontrada infectando o filamento primário da brânquia de P. lineatus e é descrita neste estudo como Henneguya prochilodus e outra espécie encontrada infectando o filamento secundário da brânquia de A. altiparanae, a qual foi proposto uma descrição expandida da Henneguya chydadea Barassa et al. (2003), previamente descrita utilizando análises morfológicas e histopatologia. Análise filogenética do gene 18S rDNA foi realizada para avaliar a relação filogenética dessas duas espécies de Henneguya com outras espécies de mixosporídeos da América do Sul e de outras regiões do mundo. / The Myxozoa parasites are obligate endoparasites that infect fish, amphibians, reptiles, mammals, waterfowl in several regions of the world, with more than 2180 described species, being among the most important fish pathogens, but little is known of this parasite in fish from Brazil. In this study were collected from March to September 2016, where 30 specimens of Curimba (Prochilodus lineatus) and seventeen specimens of lambari (Astyanax altiaparanae) from the Batalha River, in two collection sites, a collection point in the municipality of Reginópolis and another point in the municipality of Agudos, state of São Paulo. Morphological analyzes (light microscopy, histology and ultrastructural analysis), molecular biology techniques (PCR and sequencing) were used to describe two species of Henneguya. Two species were documented in this study, one of which was found infecting the primary filament of the gill of P. lineatus and is described in this study as Henneguya prochilodus and another species found infecting the secondary filament of the gill of A. altiparanae, which has been proposed an expanded description of Henneguya chydadea Barassa et al. (2003), previously described using morphological analysis and histopathology. Phylogenetic analysis of the 18S rDNA gene was performed to evaluate the phylogenetic relationship of these two species of Henneguya with other species of myxosporids from South America and other regions of the world. / Capes: 20400004

Made available in DSpace on 2014-06-12T15:07:23Z (GMT). No. of bitstreams: 2 arquivo3030_1.pdf: 2847320 bytes, checksum: 14db1ce74509f0bb0a52ad42a62e58dd (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O conceito de uma taxonomia integrativa é uma ferramenta que utiliza marcadores moleculares de DNA, caracteres ecológicos e caracteres morfológicos, a fim de auxiliar na identificação da biodiversidade global. Os gêneros de Desmodoridae estão dispostos em seis subfamílias, por apresentarem características muito diferentes. Sendo assim, um estudo de taxonomia integrativa foi assim proposto para melhor entender a diversidade da família. Um novo gênero e uma nova espécie, Spirodesma magdae nov. gen. nov. sp., foram descritas, apresentando como características principais anfídeos uniespiral com fovea anfideal circular e cavidade bucal com três dentes de tamanho iguais. Com base em evidências morfológicas e moleculares, foram testadas as relações filogenéticas entre táxons representativos das 6 subfamílias. A análise de distância genética (neighbor-joining) mostrou que Desmodoridae é uma unidade genética coesa, porém subdivida em dois agrupamentos mais similares entre si. Apesar da coesão genética de Desmodoridae, as análises moleculares de máxima parcimônia (MP) e de inferência Bayesiana (IB) indicaram que a família parece ser polifilético. Molgolaimus demani e Prodesmodora spp., são grupos irmãos e parecem não pertencer a família Desmodoridae. Spirinia e Metachromadora se comportaram como grupos monofiléticos, entretanto este último parece não pertencer a subfamília Spiriniinae. Acanthopharynx se mostrou monofilético e grupo irmão de Desmodora communis, porém ambos se mostraram distantes genético-evolutivamente de D. pontica e D. ovigera. Xyzzors sp. parece fazer parte de Desmodoridae. Pelas análises moleculares, Stilbonematinae se mostrou polifilética devido à posição de Robbea hypermnestra, Eubostrichus topiarius e E. parasitiferus; entretanto a análise filogenética (MP) por meio dos dados morfológicos apresentou Stilbonematinae como monofilético. A análise de MP por dados morfológicos mostrou que das seis subfamílias de Desmodoridae, apenas três podem ser ditas como monofiéticas, Stilbonematinae, Molgolaiminae e Prodesmodorinae. Ainda se faz necessário compreender a evolução dos caracteres morfológicos e estabelecer quais apresentam sinais filogenéticos, uma vez que os dados moleculares se mostraram mais eficazes para o estudo da diversidade e evolução de Desmodoridae do que os caracteres morfológicos aqui utilizados

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Coccidiodomycosis is a systemic infection, predominantly pulmonary, caused by the geophilic and dimorphic fungi, Coccidioides immitis and Coccidioides posadasii. In Brazil, coccidioidomycosis is associated with semi-arid areas in the Northeastern region of this country, which is considered one of the endemic areas of this disease in South America. These pathogens are morphologically indistinguishable species, but they exhibit molecular differences. Different molecular techniques have been described for the characterization of these species. The nuclear ribosomal DNA (rDNA) from Coccidioides spp. has been described as an important molecular marker for the identification, taxonomy and phylogeny. Currently, there are still shortages of maps for epidemiological approaches in order to direct the correlation between populations of Coccidioides spp. and the outbreaks of coccidiomycosis. Given the above, this study aimed at performing the molecular identification of 18 clinical and environmental isolates of C. posadasii, from Northeastern Brazil, maintained in the fungal collection of the Specialized Medical Mycology Center (CEMM), through PCR, as well as, to analyze the genetic diversity of these isolates by sequencing of 18S-28S regions of nuclear rDNA. The identification of the isolates was performed through PCR, using specific primers Coi9-1F and Coi9-R. The sequencing of the 18S-28S rDNA regions was performed through the method of chain termination by dideoxynucleotides, using the kit DYEnamicTM ET terminators cycle sequencing (GE Healthcare). The results confirmed the identification of all strains included in this study as belonging to the species C. posadasii. The phylogenetic tree based on 18S-28S rDNA region of C. posadasii from CEMM and Coccidioides spp. from Genbank. reveals the formation of a unique cluster encompassing the following strains CEMM 05-2-063, CEMM 05-2-064, CEMM 05-2-066 and CEMM 05-2-065, in a properly sustained branch, which apparently seems to group these isolates according to their geographical origin. The strains of C. posadasii showed lower genetic divergence in the ITS1 and ITS2 regions, when compared to strains of C. immitis. Analyses did not detect differences between strains of clinical origin and those of environmental origin. Further studies involving the analysis of fast evolving markers, such as microsatellites, can provide evidences to determine whether the groups found in this study are derived from a lineage of clonal reproduction. / A coccidioidomicose à uma infecÃÃo sistÃmica, predominantemente pulmonar, causada pelos fungos dimÃrficos e geofÃlicos, Coccidioides immitis e Coccidioides posadasii. No Brasil, a coccidioidomicose està associada a locais situados na zona semi-Ãrida da regiÃo Nordeste, considerada uma das Ãreas endÃmicas da doenÃa na AmÃrica do Sul. Estes patÃgenos consistem em espÃcies morfologicamente indistinguÃveis, mas que exibem diferenÃas moleculares peculiares. O DNA ribossÃmico nuclear (rDNA) de Coccidioides spp. tem sido apontado como importante marcador molecular utilizado na identificaÃÃo, taxonomia e filogenia. Atualmente, ainda hà escassez de mapas de abordagens epidemiolÃgicas para direcionar a correlaÃÃo entre as populaÃÃes de Coccidioides spp. com os surtos de coccidioidomicose. Diante do exposto, este estudo teve por objetivo, realizar a identificaÃÃo molecular de 18 isolados clÃnicos e ambientais de C. posadasii, oriundos do Nordeste brasileiro, mantidos na Micoteca do Centro Especializado em Micologia MÃdica (CEMM), atravÃs da tÃcnica de PCR, bem como, analisar a diversidade genÃtica destes isolados por meio do seqÃenciamento das regiÃes 18S-28S do rDNA nuclear. A identificaÃÃo dos isolados foi realizada por PCR utilizando os primers especÃficos Coi9-1F e Coi9-R. O sequenciamento das regiÃes 18S-28S rDNA foi realizado pelo mÃtodo da terminaÃÃo da cadeia pelo didesoxinucleotÃdeo, usando-se o kit DYEnamicTM ET terminators cycle sequencing (GE Healthcare). Os resultados confirmaram a identificaÃÃo de todas as cepas incluÃdas neste estudo, como pertencentes à espÃcie C. posadasii. A Ãrvore filogenÃtica, baseada na regiÃo 18S-28S rDNA de C. posadasii do CEMM, juntamente com sequÃncias de Coccidioides spp. depositadas no Genbank. revela a formaÃÃo de um cluster exclusivo englobando as cepas CEMM 05-2-063, CEMM 05-2-064, CEMM 05-2-065 e CEMM 05-2-066, em um ramo adequadamente sustentado, que aparentemente parece agrupar estes isolados segundo sua origem geogrÃfica. As cepas de C. posadasii apresentaram menor Ãndice de divergÃncia genÃtica nas regiÃes ITS1 e ITS2, quando comparadas Ãs cepas de C. immitis A anÃlise nÃo detectou diferenÃas entre as cepas de origem clÃnica e as de origem ambiental. Estudos posteriores envolvendo a anÃlise de marcadores de evoluÃÃo mais rÃpida, os microssatÃlites, podem fornecer evidÃncias para determinar se os agrupamentos encontrados neste estudo sÃo resultantes de uma linhagem de reproduÃÃo clonal.

Benthic diatoms are often used as indicators of water quality and past environmental conditions. This depends entirely on a reliable taxonomic system. With the advent of DNA techniques, genetic analyses can now be used in tandem with traditional microscopy in order to improve taxonomy and determine evolutionary relationships. This thesis examined a speciose genus of diatoms Neidium (> 300 species) and, using sequence data from molecular markers as well as traditional morphological analyses, investigated phylogenetic relationships. Fresh benthic samples from aquatic ecosystems in Eastern North America were collected; Neidium taxa were examined using light and scanning electron microscopy then compared to the original specimen types. A total of 124 individual cells were retrieved, amplified, and sequenced for four molecular markers (rbcL, 18S, psbA, and psbC). Phylogenetic reconstructions were completed using Maximum likelihood and Bayesian analyses; when compared with morphological analyses this led to the delineation of several novel Neidium species.

Les ribosomes sont des complexes nucléoproétiques responsables de la traduction. Chez les eucaryotes, la biogenèse du ribosome est un processus complexe très régulé qui fait intervenir un nombre important de facteurs d’assemblages (~200). La construction d’un ribosome est initiée dans le nucléole puis continue dans le nucléoplasme et se termine dans le cytoplasme. La maturation cytoplasmique de la petite sous-unité ribosomale implique la dissociation séquentielle des facteurs d’assemblage tardifs et la maturation finale de l’ARNr 18S. Ce processus est catalysé par l’endonucléase Nob1 qui assure la coupure de l’extrémité 3’ du précurseur de l’ARNr 18S (pré-18S) aboutissant à sa forme mature. Ce mécanisme est coordonné par la protéine Pno1 qui est le partenaire de Nob1. Des informations détaillées sur l’architecture des particules pré-ribosomiques nous ont permis de mieux comprendre les différents intermédiaires de la biogenèse. Cependant, certains aspects fonctionnels comme la conformation adoptée par Nob1 pour assurer la coupure du site D du pre-18S reste encore flou. L’objectif de mon travail a été de mieux comprendre les aspects très tardifs de la maturation cytoplasmique du ribosome. Pour ce faire, nous avons redéfini l’organisation modulaire de l’endonucléase Nob1 chez les eucaryotes pour ensuite étudier son mode d’interaction avec son partenaire Pno1. Des tests fonctionnels in vitro ont été effectués pour étudier le rôle de Pno1 dans la régulation de la coupure par Nob1.Nos résultats nous ont permis de montrer que le domaine catalytique de Nob1 adopte une conformation atypique. En effet le domaine PIN est composé de deux fragments (res 1-104 and 230-255) séparé par une boucle interne qui est importante pour la reconnaissance avec son partenaire Pno1. Nos études nous ont également montré que Pno1 inhibe l’activité de Nob1 probablement en reconnaissant directement l’ARNr substrat, masquant ainsi le site de coupure de l’endonucléase. Ces résultats sont complémentaires et cohérents avec les données structurales de cryo-EM de la particule pré-40S humaine récemment publiées. En effet, Nob1 est dans une conformation incapable de couper le pré-ARNr puisque son domaine catalytique se retrouve à une distance d’environ 30Å de son ARN substrat. Ce phénomène implique donc des changements de conformations ou encore la nécessité de protéine accessoire pour déplacer certains facteurs. La protéine Cinap est impliqué dans la maturation de l’ARNr 18S. Nos études d’interaction avec les protéines localisées au niveau de la plateforme (à savoir RPS14, RPS26, le complexe Nob1/Pno1) ont permis de montrer que Cinap pouvait former un complexe tripartite avec l’endonucléase Nob1 et son partenaire Pno1. De plus, Cinap est capable de reconnaitre RPS26 dans un complexe RPS14-dépendant. Il est important de noter que RPS26 est un composant de la petite sous-unité qui remplace Pno1 dans le ribosome mature. De ce fait le recrutement de RPS26 au sein du pré-ribosome nécessite la dissociation de Pno1 et cet échange serait assurée par Cinap. Sur la base des travaux effectués, nous pouvons proposer un modèle de maturation où la formation du complexe Cinap/Pno1 induirait un changement de conformation permettant à Nob1 de reconnaitre son substrat et donc de catalyser la coupure du site D qui aboutit à la maturation de l’ARNr 18S et donc à la production de la sous-unité 40S mature. / Ribosomes are translational machineries universally responsible of protein synthesis. In eukaryote, ribosome assembly is a complex and highly regulated process that requires coordinated action of more than 200 biogenesis factors. Ribosome assembly is initiated in the nucleolus, continues in the nucleoplasm and terminates in the cytoplasm. The cytoplasmic maturation events of the small ribosomal subunit are associated with sequential release of the late assembly factors and concomitant maturation of the pre-rRNA. During final maturation of the small subunit, the pre-18S rRNA is cleaved off by the endonuclease Nob1, which activity is coordinated by its binding partner Pno1. Detailed information on pre-ribosomal particle architectures have been provided by structural snapshots of maturation events. However, key functional aspects such as the architecture required for pre-rRNA cleavage have remained elusive. In order to better understand these late steps of cytoplasmic pre-40S maturation, we first redefine the domain organization of Nob1, then study its binding mode with Pno1 using different tools such as sequence analysis, structure prediction and biochemical experiments and, we then performed functional assay to elucidate the role played by Pno1 during the pre-18S rRNA maturation.Our results have shown that eukaryotic Nob1 adopts an atypical PIN domain conformation: two fragments (res 1-104 and 230-255) separated by an internal loop, which is essential for Pno1 recognition. We also found out that Pno1 inhibits Nob1 activity likely by masking the cleavage site. Our findings further support the recently published cryo-EM structure of the pre-40S, where Nob1 displays an inactive conformation. Moreover, 18S rRNA 3’-end cleavage has to happen and this implies structural rearrangement or requirement of some accessory proteins such as Cinap, an atypical kinase involved in pre-18S processing. Studying the interplay between proteins localized in the pre-40S platform (RPS14, RPS26, Nob1/Pno1 complex) has shown that Cinap is able to form a trimeric complex with Nob1 and its binding partner Pno1. Furthermore, Cinap can recognize RPS26 in a RPS14-dependent manner, which had already been studied with its yeast counterpart. It is important to note that RPS26 is the ribosomal protein replacing Pno1 in the mature ribosome. Our finding clearly suggests a mechanism where RPS26 recruitment to the ribosome requires Pno1 dissociation. This exchange would be carried out by Cinap. Therefore, we can suggest a simplified model as follow: upon binding with Pno1, the newly formed complex (Cinap/Pno1) will trigger a conformational change, which will allow the endonuclease Nob1 to reach its substrate (D-site) and perform its cleavage resulting in mature 18 rRNA generation.

In the present study a character data set suitable for cladistic analysis at the family level was developed. A data matrix consisting of 50 morphological characters from 15 families of tardigrades 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, Eohypsibiidae 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. The 18S rRNA gene sequence of Batillipes mirus Richters, 1909 and Calohypsibius schusteri Nelson & McGlothlin, 1996 were obtained and their addition to a previously published dataset supports the monophyly of Heterotardigrada and of Parachela versus Apochela within the Eutardigrada.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19960号 / 理博第4227号 / 新制||理||1607(附属図書館) / 33056 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 中野 伸一, 教授 木庭 啓介, 教授 沼田 英治 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

No description available.

O filo Myxozoa possui uma grande diversidade, sendo conhecidas cerca de 2300 espécies, as quais infectam principalmente peixes, mas também anfíbios répteis e aves. Para este estudo, coletas dos peixes de água doce foram realizadas no Pantanal Mato-grossense (estados de Mato Grosso e do Matogrosso do sul) e no Rio Mogi Guaçu e piscicultura do CEPTA/ICMBio (estado de São Paulo), visando estudos moleculares e morfológicos de mixosporídeos parasitas de 6 espécies de peixes. Os resultados das análises moleculares (amplificação e sequenciamento do gene 18S rDNA) e morfológicas revelaram a ocorrência de 11 espécies de mixosporídeos, sendo cinco parasitas comuns a Pseudoplatystoma corruscans e Pseudplatystoma fasciatum, três parasitas de Salminus brasiliensis, uma espécie parasita de Brycon hilarii, uma de Zungaru jahu e outra de Piaractus mesopotamicus. Das onze espécies, cinco ainda não são descritas pela literatura. A análise filogenética, utilizando o método de Neighbor-Joining, mostrou que o agrupamento das espécies ocorre principalmente de acordo com a proximidade filogenética de seus hospedeiros e que todas as espécies da América do Sul agruparam em um clado monofilético. Foi observado, em alguns pontos da árvore filogenética, que o tropismo de tecido e/ou órgão de infecção caracteriza um importante fator de seleção evolutiva. Com menor frequência também foi observado alguns agrupamentos resultantes de parasitas cuja maior relação aparente era a sua localização geográfica, porém, novos estudos ainda são necessários para determinar o verdadeiro papel deste fator na evolução dos mixosporídeos. / The phylum Myxozoa has a great diversity, with about 2300 known species, which infect mainly fishes, but also amphibians, reptiles and birds. In this study, freshwater fishes were caught in the Brazilian Pantanal wetland (Mato Grosso and Mato Grosso do Sul states) and in the Mogi Guaçu River and CEPTA/ICMBio\'s fishfarm (São Paulo state) aiming the molecular and morphological studies of myxosporeans parasites of 6 fish species. The results of molecular (amplification and sequencing of the 18S rDNA gene) and morphological analysis revealed the occurrence of 11 species of myxosporeans, five of them infecting both Pseudoplatystoma corruscans and Pseudoplatystoma fasciatum, three parasites of Salminus brasiliensis, one specie infecting Brycon hilarii, one infecting Zungaro jahu and another infecting Piaractus mesopotamicus. Of these eleven species, five are not yet described by literature. The phylogenetic analysis, using the Neighbor-joining method, showed that the species clustered mainly according to the phylogenetic distance of their hosts and that all species of South America were grouped in a monophyletic clade. In some positions of the phylogenetic tree was observed that tissue tropism and/or organ of infection characterized an important factor in evolutionary selection. Less frequently was also observed some groups containing species which the major apparent relation is its geographical position, however, new studies are still needed to determine the true role of this factor in the evolution of myxosporeans.