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Electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between the two species was high, 0.887, indicating the taxa are closely related. Nevertheless, data accumulated point to the conclusion that the two species maintain electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between the two species was high, 0.887, indicating the taxa are closely related. Nevertheless, data accumulated point to the conclusion that the two species maintain their genetic integrity throughout their ranges. their genetic integrity throughout their ranges.

Orientador: Irani Quagio-Grassiotto, Claudio de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-09T07:10:58Z (GMT). No. of bitstreams: 1 Santos_MariaAngelicaSpadella_D.pdf: 20876442 bytes, checksum: 2ea26884c55504cdea627d8003755c40 (MD5) Previous issue date: 2007 / Resumo: A ordem Siluriformes compreende um grupo diverso e amplamente distribuído dentre os Ostariophysi, apresentando 36 famílias com aproximadamente 480 gêneros e mais de 3.000 espécies. Entre os grupos de Siluriformes neotropicais, reconhecidamente monofiléticos, está a superfamília Loricarioidea. Os relacionamentos filogenéticos entre as famílias de Siluriformes, sugerem que Loricarioidea é grupo irmão de Amphiliidae, uma família africana de Siluriformes. A superfamília Loricarioidea encontra-se atualmente constituída por seis famílias: Nematogenyidae, Trichomycteridae, Callichthyidae, Scoloplacidae, Astroblepidae e Loricariidae. Apesar do conhecimento atual sobre os relacionamentos entre as famílias de Siluriformes vir sendo obtido com base em caracteres osteológicos, outros dados como a ultra-estrutura da espermiogênese e dos espermatozóides parecem ser potencialmente úteis na elucidação dos relacionamentos de grupos. O objetivo deste estudo foi a realização da análise filogenética da superfamília Loricarioidea, com base nas características ultra-estruturais da espermiogênese e dos espermatozóides, visando testar a real habilidade destes dados na resolução dos relacionamentos filogenéticos intra e inter-familiar, bem como na ordem Siluriformes. Foi feita a descrição das características ultra-estruturais das células germinativas masculinas em 27 representantes de diferentes famílias de Loricarioidea. A análise geral dos dados obtidos revelou que quando essa classe de caracteres ultra-estruturais reprodutivos é utilizada em grupos mais restritos como a superfamília Loricarioidea, observa-se que ela pode ser mais informativa e pode corroborar o monofiletismo de alguns grupos. Entretanto, o uso desses caracteres nas análises filogenéticas em nível de ordem não é informativo, uma vez os grupos sugeridos são muito incongruentes com a hipótese de relacionamento disponível para os Siluriformes. Além disso, alguns caracteres que poderiam representar sinapomorfias, tornam-se homoplasias quando se considera a ocorrência da mesma característica em outros grupos não relacionados. Portanto, o emprego desses caracteres ultra-estruturais reprodutivos em análises filogenéticas deverá ser criteriosamente planejado, evitando-se interpretações equivocadas / Abstract: The order Siluriformes comprises the most diverse and widely distributed ostariophysan groups, presenting thirty-six families with approximately 480 genera and over 3.000 species. Among the neotropical siluriform lineages likely to be monophyletic is the superfamily Loricarioidea. The relationships among catfish families suggest that Loricarioidea is sister group of Amphiliidae, an African siluriform family. The Loricarioidea is constituted by six families: Nematogenyidae, Trichomycteridae, Callichthyidae, Scoloplacidae, Astroblepidae, and Loricariidae. Although the current knowledge of the relationships among siluriform families has been acquired on the basis on osteological characters, other data such as the spermiogenesis and spermatozoal ultrastructure seem be potentially useful in the clarification of the relationships of the groups. The aim of the present study was to develop a phylogenetic analysis of the superfamily Loricarioidea, using the ultrastructural characteristics of both spermiogenesis and spermatozoa as a test to evaluate the ability of this data in resolving the phylogenetic relationships inside the families, among families and in the order Siluriformes. The description of the ultrastructural characteristics of male germinative cells in 27 specimens of different families of Loricarioidea was presented. The general analysis of the data obtained revealed that when this class of reproductive ultrastructural characters is employed in a more restrict group, as the superfamily Loricarioidea, it is really informative and can strongly support the monophyly of some groups. However, the phylogenetics analysis using these characters is not informative at order level as the suggested groups are very incongruent with the available hypotheses for Siluriformes. Moreover, some characters that could represent synapomorphies, change to homoplasies considering the occurrence of the same characters in other unrelated groups. Then, the use these reproductive ultrastructural characters in phylogenetics analysis should be carefully planed to avoid erroneous conclusions / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural

Extensively migrating population of neural crest cells, which contributes to many tissues and builds up most of craniofacial vertebrate structures, has a crucial role in embryonic development of vertebrate body. The migratory pathways of neural crest cells are thought to be very conserved throughout the vertebrates and cranial neural crest migration is defined by progression of three migratory streams: trigeminal, hyoid and a common branchial stream. In this diploma thesis, migration of cranial neural crest was analysed using embryos of the Senegal bichir (Polypterus senegalus) and of sterlet (Acipenser ruthenus), which represent two basal-most lineages of extant ray-finned fishes. A combination of several techniques was used in both species in order to study cranial neural crest cells from their sites of origin to post- migratory stages and the pattern of migration was compared and discussed in revealed embryonic context. In the Senegal bichir the hyoid neural crest stream was shown to migrate first and it is also the most abundant; this heterochrony shift is apparently related to formation of external gills, which in bichir are situated on the hyoid arch only. In sterlet, neural crest cells migrate in a classic pattern of three progressive streams but their dynamics and patterning is influenced by...