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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Anel?deos Polychaeta associados a bancos de corais de profundidade da Bacia de Campos ? Rio de Janeiro, Brasil / Polychaeta associated with deep-sea coral reefs from Campos Basin, Rio de Janeiro, Brasil

Miranda, Vin?cius da Rocha 26 June 2013 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-04-04T11:10:45Z No. of bitstreams: 1 2013 - Vin?cius da Rocha Miranda.pdf: 4210864 bytes, checksum: 3c37254eedb367413a77718eae172a75 (MD5) / Made available in DSpace on 2017-04-04T11:10:45Z (GMT). No. of bitstreams: 1 2013 - Vin?cius da Rocha Miranda.pdf: 4210864 bytes, checksum: 3c37254eedb367413a77718eae172a75 (MD5) Previous issue date: 2013-06-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Cold-water coral reefs are of great ecological importance, they can support a great diversity associated with. They can offer a sheltered, three-dimensional, micro-habitat to many species. Studies involving the Brazilian deep-sea coral reefs, and the fauna which composes it, are recent and still scarce. These reefs were studied only in terms of the species of coral which composes it and their distribution in our coast, as the benthic fauna which are associated with this environment. Two projects, CAP-BC and ECOPROF, coordinated by CENPES/PETROBRAS, surveyed the Campos Basin (located at the northeast of Rio de Janeiro) with the objective of studying this environment and the associated fauna. On each project samples of the reef-building corals were collected with a ROV, at depths from 245 to 1100m. Five species of coral were surveyed: Solenosmilia variabilis Duncan, 1873, Lophelia pertusa (Linnaeus, 1758), Enallopsammia rostrata (Portual?s, 1758), Madrepora oculata Linnaeus, 1758 and Errina sp.,and fixed in formalin 10% and sorted at the laboratory. Here in, we present the first, qualitative, results from the polychaetes found in association with the coral reefs in Campos BasinThe specie of Eunice prognatha McIntosh, 1885 were the most abundant, followed by Harmothoe gilchristi (Day, 1960) and Nicon maculata Kimberg, 1866. The majority of polychaetes were found associated to the coral S. variabilis, followed by E. profunda and L. pertusa, both M. oculata and Errina sp. were the corals with less associated polychaetes. Five new species of Polychaeta are reported: Harmothoe sp. (Polynoidae), Pholoides sp. (Sigalionidae), Leocratides sp. (Hesionidae), Euchone sp. (Sabellidae) and Ophryotrocha sp. (Dorvilleidae).Specimens identified as Glycerella magellanica (McIntosh, 1885), Harmothoe gilchristi (Day, 1960), Eunice gracilicirrata (Treadwell, 1922), Eunice prognatha McIntosh, 1885, Pionosyllis procera Hartman, 1965, Haplosyllis ohma (Imajima & Hartman, 1964) and Nicon maculata Kimberg, 1866, are new occurrence for the Brazilian coast. Two other species, Filogranula revizee Nogueira & Abbud, 2009 and Notopygos crinita Grube, 1855had their range of occurrence extended. This is the first study aiming on the polychaetes associated with deep sea corals in the Brazilian waters, further studies should be conducted to better understand the distribution of species described here in, as well as to better understand the polychaete assemblage associated with each species of coral. / Recifes de corais de profundidade possuem uma grande import?ncia ecol?gica, uma vez que podem abrigar uma grande diversidade de esp?cies associadas. Isso ? poss?vel gra?as ? sua conforma??o tridimensional que proporciona uma alta hetereogenidade espacial, criando um ambiente protegido para muitas esp?cies. No Brasil, estudos sobre corais. de profundidade, s?o escassos e recentes. Muitos destes se limitam a descrever as esp?cies de corais encontradas e a sua distribui??o pela costa brasileira assim como organismos bent?nicos associados a eles. Recentemente foram realizados dois projetos coordenados pela CENPES/PETROBRAS, CAP-BC e ECOPROF com objetivo de realizar um levantamento dos recifes de corais de profundidade, bem como das esp?cies associadas a estes, na regi?o da Bacia de Campos (noroeste do estado do Rio de Janeiro). Em cada um desses projetos foi utilizado um ROV para coletar amostras nas profundidades entre 300 e 1100 metros. Cinco esp?cies de corais formadores desse ecossistema foram coletadas: Solenosmilia variabilis Duncan, 1873, Lophelia pertusa (Linnaeus, 1758), Enallopsammia rostrata (Portual?s, 1758), Madrepora oculata Linnaeus, 1758 and Errina sp., cada amostra foi fixada em uma mistura tamponada de formalina (10%), para posterior triagem em laborat?rio. Aqui apresentamos o estudo dos poliquetas associados a estes corais na Bacia de Campos. A esp?cie Eunice prognatha McIntosh, 1885 foi a mais abundante, seguida por Harmothoe gilchristi (Day, 1960) e Nicon maculata Kimberg, 1866. O coral S. variabilis foi o que apresentou o maior n?mero de esp?cies associadas, seguida dos corais E. rostrata e L. pertusa, j? as esp?cies M. oculata e Errina sp. foram os corais com menos esp?cies de poliquetas encontrados. Foram reportadas cinco novas esp?cies de poliquetas Harmothoe sp. (Polynoidae), Pholoides sp. (Sigalionidae), Leocratides sp. (Hesionidae), Euchone sp. (Sabellidae), e Ophryotrocha sp. (Dorvilleidae). O total de oito esp?cies foram registradas pela primeira vez para a costa brasileira: Glycerella magellanica (McIntosh, 1885), Harmothoe gilchristi (Day, 1960), Eunice gracilicirrata (Treadwell, 1922), Eunice prognatha McIntosh, 1885, Pionosyllis procera Hartman, 1965, Haplosyllis ohma (Imajima & Hartman, 1964), e Nicon maculata Kimberg, 1866. Duas outras esp?cies, viii Filogranula revizee Nogueira & Abbud, 2009 e Notopygos crinita Grube, 1855, tiveram suas ?reas de ocorr?ncia ampliadas. Este ? o primeiro estudo focando nos poliquetas associados aos corais de profundidade da costa brasileira. Novos estudos devem ser realizados para melhor compreender a distribui??o das esp?cies descritas neste trabalho, assim como entender as poss?veis associa??es destas com as esp?cies de coral desse ecossistema
102

Genome Size Diversity and Patterns within the Annelida

Forde, Alison Christine 24 January 2013 (has links)
This thesis concerns genomic variation within the Annelida, for which genome size studies are few and provide data for only a handful of groups. Genome size estimates were generated using Feulgen image analysis densitometry for 35 species of leeches and 61 polychaete species. Relationships were explored utilizing collection location and supplementary biological data from external sources. A novel, inverse correlation between genome size and maximum adult body size was found across all leeches. Leeches that provide parental care had significantly larger genome sizes than leeches that do not. Additionally, specimens identified as Nephelopsis obscura exhibited geographic genome size variation. Within the Polychaeta, Polar region polychaete genomes were significantly larger than those of Atlantic and Pacific polychaetes. These studies represent the first exploration of leech genome sizes, and provide base evidence for numerous future studies to examine relationships between genome size and life history traits across and within different annelid groups.
103

Neural development in the larva of HarmothÜe imbricata (Linné) : (Polychaeta : polynoidae)

Hsieh, Jane, 1960- January 1984 (has links)
No description available.
104

Community structure and function of macrobenthos in three feature areas of the Natal Bight, South Africa.

Untiedt, Candice Bobby. January 2013 (has links)
The Natal Bight off the east coast of South Africa is a unique shelf habitat, exhibiting high secondary productivity and supporting high diversity. Ecosystem attributes are influenced by local oceanographic features and outwelling via one of the largest rivers in the country. This study forms part of a larger, multi-institutional, multi-disciplinary study under the second phase of the African Coelacanth Ecosystem Programme (ACEP II) Natal Bight Project, investigating how material sources, posited to be derived from these features, shape the ecological structure and functioning of the region. Macrobenthic samples were collected along cross shelf transects off Richard’s Bay, Durban and the Thukela River mouth during two cruises, corresponding with periods of variable rainfall. Macrobenthic communities were classified taxonomically, to the lowest level possible, and functionally. Community patterns were investigated within and between feature areas and related to measurable environmental factors in order to determine environmental drivers and assess the importance of identified oceanographic features. Environmental parameters measured included sedimentary characteristics as well as physico-chemical conditions in the surrounding pelagic milieu. A total of 38 215 individuals belonging to 826 taxa were recorded from the three feature areas, of which the majority were Polychaeta and Crustacea. An in-depth investigation of the polychaete component has shown that this group can be used as a proxy for the whole macrobenthic community which has important implications for future studies. Facultative feeding modes dominated the trophic functioning macrobenthic communities sampled on the Natal Bight. Primary community metrics of abundance and numbers of macrobenthic taxa were reduced from the high to low rainfall period but differences were not significant, probably due to the lack of temporal repetition. The Thukela feature area was found to support the most abundant and taxon rich macrobenthic community. Mid-shelf stations sampled along the Thukela and Durban transects were in close proximity to the coarse paleo-dune cordon, running along the 60 m isobath and supported a diverse assemblage. Despite the lack of temporal repetition in the present study, there were significant short-term changes in the structure and functioning of macrobenthic communities on the Thukela shelf. This suggests that Thukela River outflow has a significant effect on the functioning of the Natal Bight ecosystem. This was surprising given the importance which has previously been placed on the Cape St. Lucia upwelling cell in terms of contributing nutrients and sustaining biological productivity and diversity on the Natal Bight. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2013.
105

Functional genetic analysis of two non-model marine invertebrates : physiologically and environmentally induced changes in gene expression /

Phillips, Michelle René, January 2007 (has links)
Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 179-196). Also available for download via the World Wide Web; free to University of Oregon users.
106

Sistema planctônico da região do emissário submarino de esgotos de Ipanema, Rio de Janeiro, RJ, populações zooplanctônicas : Annelida Polychaeta

Machado, Maria Cordélia Soares 15 September 1986 (has links)
Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2017-10-18T20:53:41Z No. of bitstreams: 1 200794.pdf: 49807309 bytes, checksum: 79f95dcfe52a1c426c83faaabbde276b (MD5) / Made available in DSpace on 2017-10-18T20:53:41Z (GMT). No. of bitstreams: 1 200794.pdf: 49807309 bytes, checksum: 79f95dcfe52a1c426c83faaabbde276b (MD5) Previous issue date: 1986-09-15 / Evidencia as características hidrobiológicas do litoral de Ipanema, estudamos diversos parâmetros climatológicos, hidrológicos e biológicos e suas variações espaciais, nas duas estações, próximas à desembocadura do “Emissário Submarino de Esgotos de Ipanema”, e temporais no período de 1979 a 1983. Discutimos cada fator estudado e os correlacionamos matematicamente, visando a compreender a estrutura hidrobiológica desta área particular. Apresentamos algumas conclusões em relação às massas de águas predominantes, a situação quanto ao impacto desequilibrador do ecossistema, estado geral da população fitoplanctônica e o standing-stock da região. Dentre os zooplanctontes coletados em três estações desta área dirigimos o estudo qualitativo para os Annelida Polychaeta. Achamos seis espécies distribuídas em três famílias: Iospilidade (3), Typhloscolecidae (2) e Tomopteridae (1). As espécies encontradas são descritas e ilustradas. São estudadas biogeograficamente e plotadas quanto a sua distribuição mundial. São levantadas as presenças nas massas de água mais características desta região litorânea. São estudadas algumas larvas planctônicas das seguintes famílias bentônicas: Polynoidae, Spionidae e Poecilochaetidae, além dos estágios estoloníferos da família Syllidae (estágio Polybostrichus e Chaetosyllis). / Several climatological, hidrological and biological parameters, as well as their spatial and temporal variations are studied to put in evidence the hidrobiological characteristics of the Ipanema littoral. The study was carried out in two stations close to the outlet of the Submarine Sewage Discharger of Ipanema, throughout the period 1979/ 1983. Every factor was discussed and a mathematical correlation was established to make a full understanding of the hydrobiological structure of that particular area. Some conclusions are presented: the predominant water mass, the situations as to the environment disturbance, the general state of the phytoplanktonic population and the standing stock of the region. The qualitative study was directed to the Annelida Polychaeta out of the zooplankton collected in that area. Six species, distributed into three families, Iospilidae (3), Typhloscolecidae (2) and Tomopteridae (1); are studied with descriptions and illustrations of those species, which are biogeographically studied and ploted as to their worldwide distribution. A survey is made of their presence in the most characteristic water mass of the littoral region of Ipanema. Some planktonic larvae, belonging to the benthonic families Polynoidae, Spionidae and Poecilochaetidae are studied, as well as the stoloniferous stages of the Syllidae family (stages Polybostrichus and Chaetosyllis).
107

Biologia populacional do poliqueta Polydora neocaeca associado a bancos de Mytella charruana = Population biology of the polychaete Polydora neocaeca associated with Mytella charruana mussel beds / Population biology of the polychaete Polydora neocaeca associated with Mytella charruana mussel beds

Daolio, Rachel Furioso, 1985- 26 August 2018 (has links)
Orientador: Antonia Cecília Zacagnini Amaral / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T06:06:23Z (GMT). No. of bitstreams: 1 Daolio_RachelFurioso_M.pdf: 2566347 bytes, checksum: 646f1db51330af90d55b405f39cb815b (MD5) Previous issue date: 2014 / Resumo: Os polidorídeos são poliquetas da família Spionidae cuja característica principal é a presença de cerdas em forma de ganchos no 5° setígero. Algumas espécies habitam fundos não consolidados, enquanto que outras, como Polydora neocaeca, habitam substratos consolidados, podendo ou não perfurar estruturas calcárias como corais e conchas de moluscos. A forma de perfuração é pouco compreendida, existindo hipóteses de que seja mecânica, química ou a combinação desses processos. A infestação raramente causa a morte direta dos hospedeiros, porém os torna suscetíveis a outros parasitas e doenças. Por essa razão, os polidorídeos são considerados pestes pela indústria de moluscos. Polydora neocaeca parasita o mexilhão Mytella charruana que pode ser encontrado formando bancos na região entremarés de praias abrigadas. Dois bancos de M. charruana localizados nas praias do Camaroeiro e da Cidade na enseada de Caraguatatuba (Litoral Norte do Estado de São Paulo) foram estudados de março de 2006 a março de 2007. Na porção central de cada banco, foram traçados transectos perpendiculares à linha d¿água, sendo sorteado mensalmente um de cada banco para amostragem. Em cada transecto, substratos de três níveis foram coletados com o auxílio de um delimitador de 0,04 m² para a triagem dos mitilídeos e dos polidorídeos. O presente trabalho teve como objetivo (1) caracterizar as duas áreas de estudo quanto a variáveis ambientais (perfil praial, salinidade da água intersticial, temperaturas do ar e do sedimento e granulometria, teor de calcário e conteúdo de matéria orgânica do sedimento) e estrutura (densidade de M. charruana); (2) analisar a morfometria dos dois grupos de P. neocaeca (do Camaroeiro e da Cidade); e (3) avaliar a biologia populacional destes, incluindo sua dinâmica, estrutura etária, recrutamento, crescimento e mortalidade. O perfil da praia do Camaroeiro permitiu classificá-la como de dissipativa a intermediária e, o da Cidade, como intermediária do tipo terraço de baixamar. A densidade de M. charruana, o conteúdo médio de calcário e a fração do sedimento de silte + argila foram maiores no banco da Cidade. As demais variáveis foram semelhantes entre os dois bancos. O único modelo de crescimento alométrico que apresentou um bom suporte ás medidas morfométricas dos dois grupos de P. neocaeca foi o modelo de dois segmentos. Esses polidorídeos apresentaram alometria negativa, ou seja, ao longo do seu desenvolvimento o aumento no número total de setígeros é proporcionalmente menor do que o aumento no comprimento total. A largura do setígero 5 foi selecionada como a medida parcial mais adequada para a estimativa do tamanho total dos indivíduos. Apesar da diferença estrutural entre os bancos, P. neocaeca apresentou padrão temporal de recrutamento e parâmetros de crescimento semelhantes entre os dois grupos. Isso sugere que há fluxo gênico (via dispersão) entre eles, tratando-se de uma única população. Porém, a abundância, o tamanho médio da largura do setígero 5 e a longevidade desses polidorídeos foram maiores na Cidade, enquanto que sua mortalidade foi maior no Camaroeiro. Essas diferenças estão mais relacionadas á densidade de mitilídeos hospedeiros (maior no banco da Cidade) do que ás demais variáveis analisadas / Abstract: Polydorids are polychaetes from the Spionidae family whose main characteristic is the presence of modified hooks on the 5th setiger. Some species inhabit soft substrata, while others, such as Polydora neocaeca, inhabit hard substrata, boring or not self-excavated burrows on calcareous structures such as corals and mollusk shells. The boring mechanism is poorly understood and might be mechanical, chemical or the combination of these processes. The infestation rarely causes the direct death of hosts, but makes them susceptible to other parasites and diseases. Thus polydorids are considered as pests by the fishery industry. Polydora neocaeca parasites the Mytella charruana mussel, which can be found forming beds on the intertidal region of sheltered beaches. Two M. charruana beds located at the Camaroeiro and the Cidade beaches from Caraguatatuba Bay (North Coast of São Paulo State) were studied from March 2006 to March 2007. On the central portion of each mussel bed, transects were delimited perpendicular to the waterline, with one from each mussel bed being monthly sampled. On each transect, three levels of substrata were collected with a 0.04 m² corer in order to sample the mytilid and the polydorid individuals. This study aimed to (1) characterize the two sites regarding their environmental variables (beach slope, interstitial water salinity, air and sediment temperatures, and sediment granulometry, calcareous content and organic matter) and structure (M. charruana density); (2) analyze the morphometrics of the two groups of P. neocaeca (Camaroeiro and Cidade); and (3) assess the population biology of these groups, including their dynamics, size structure, recruitment, growth and mortality. The Camaroeiro beach slope enabled its classification as a dissipative to intermediate beach, and the Cidade one, as a low-tide terrace intermediate beach. The M. charruana density, the mean calcareous content, and the silt + clay sediment fraction were higher at the Cidade mussel bed. The other variables were similar between the two beds. The only allometric growth model that showed good support as to the morphometric measures of both P. neocaeca groups was the two segments model. These polydorids showed negative alometry, which indicates that, along their development, the total number of setigers increase is proportionately smaller than the total length increase. The width of the setiger 5 was selected as the most appropriate partial measure for estimating the individuals total size. Despite the structural difference between the mussel beds, P. neocaeca presented similar recruitment temporal pattern and growth parameters between the two groups. This suggests that there is a gene flow (by dispersal) between them, which constitute a single population. However, the abundance, the mean width of the setiger 5 and the longevity of these polydorids were higher at Cidade, whereas their mortality was higher at Camaroeiro. These differences are more related to the host density (higher at the Cidade mussel bed) than to the other analyzed variables / Mestrado / Ecologia / Mestra em Ecologia
108

An investigation into the feeding biology and factors influencing the population dynamics of Terebrasabella heterouncinata (Polychaeta: Sabellidae), a problematic tube-dwelling polychaete in farmed abalone in South Africa

Chalmers, Russell January 2003 (has links)
Since the discovery of a new species of sabellid worm in 1993, the Californian and South African abalone industries have experienced increasing shell breakage and reduced growth rates of abalone, resulting in reduced market value of product. This polychaete worm can reach very high infestation levels. It was described as Terebrasabella heterouncinata in 1999, having originated from the South African coastline where it had been observed on several wild mollusc species. Although not a shell borer, it occupies tubes on the growing edge which are formed by deposition of nacreous shell over sabellid larvae by the host abalone. Heavy sabellid infestation levels have placed the economic viability of several South African farms under threat. Past research methods have not been successful in establishing effective means of eradication or control, partly due to the lack of knowledge of basic biological information on this species. This study forms the first part of an ongoing research project into the biology of terebrasabella heterouncinata. Abalone farms in South African utilise two main diets in abalone culture. An artificial formulated feed, Abfeed, is produced in South Africa and is used by the majority of farms as it increases abalone growth rate. Kelp, a natural diet of abalone, is harvested and also used as a feed. Farmers have observed higher sabellid infestation levels on Abfeed-fed abalone and suspect that diet may be an important factor influencing sabellid infestation. Abalone stocking density has also been identified as a potential factor influencing sabellid population growth on commercial farms. In order to better understand sabellid nutrition, the feeding behaviour of the sabellid in response to suspended solids of various particle size classes from both abalone diets were investigated. Both the effect of abalone diet and stocking density and their effects on sabellid morphometrics were quantified. The proximate composition and particle size distribution of suspended-solids present within kelp and Abfeed abalone raceways were also quantified. Results indicate that sabellid feeding follows no structured behavioural pattern for both abalone diets. The quantity of suspended solids in kelp raceways was greater than in Abfeed raceways (p<0.02) while there was no difference in particulate level between three abalone stocking densities (p>0.05). Protein (p<0.0001) and energy (p<0.0.1) levels of suspended solids were significantly greater in raceways dedicated to feeding Abfeed. The infestation level (number of tubes/centimetre on the grwoing edge) was significantly higher (p<0.001) in Abfeed-fed abalone. The morphometrics of the sabellids indicated that sabellids from Abfeed-fed abalone were larger in various body measurements: length (p<0.00001); neck width (p<0.001); base width (p<0.001); and surface area (p<0.001). This study suggests that abalone diet has an important influence on the infestation level and size of sabellids and that this is likely to be due to the fragmentation and leaching of nutrients from the artificially enriched commercial abalone diet.
109

Brachiopoda a polychaeta v tafocenózách české křídové pánve / Brachiopoda and polychaeta in Taphocenoses of the Bohemian Cretaceous Basis

Sklenář, Jan January 2013 (has links)
The sesile suspension feeders of Brachiopoda and Polychaeta phyla are relatively well represented in the Bohemian Cretaceous Basin (BCB), and show significant diversity. All three subphyla of Brachiopoda (Linguliformea, Craniiformea and Rhynchonelliformea) are present in the fossil record of the sedimentary basin infill; from Polychaeta, there has hith- erto been evidence of only the Canalipalpata subclass members that created solid, usually carbonatic tubes. In both abundancy and diversity, the most richest associations of fossil brachiopods and polychaets occure in near-shore facies of the Cenomanian to the Lower Turonian, and hemipelagic facies of the Late Turonian age. Prior research, as shows the literature survey given by the author, has been focused mainly on representatives of both groups of near-shore facies origin. The aim of this thesis is to fill in the existing gaps in our understanding of these groups within the BCB. This objective is accomplished in the form of a series of studies (Sklenář & Simon 2009, Vodrážka & al. 2009, Sklenář & al., in press) elaborating the following topics in detail: (A) taxonomy, distribution, morphology, variabil- ity, evolutionary relationships and stratigraphic significance of cancellothyrid brachiopod Gyrosoria abundant in the Middle and particularly in...
110

Ultrastrukturuntersuchungen der Segmentalorgane, der Spermien und der Brutpflegestrukturen der Syllidae (Annelida: Polychaeta)

Kuper, Michael 13 February 2002 (has links)
Die Polychaetenfamilie Syllidae ist mit über 600 Arten das größte Taxon innerhalb der Phyllodocida. Die Syllidae werden traditionell in vier Unterfamilien eingeteilt: Autolytinae, Exogoninae, Eusyllinae und Syllinae. Obwohl diese Einteilung umstritten ist, hat sie bis heute ihre Gültigkeit. Als die zum Grundmuster der Syllidae gehörigen Segmentalorgane werden Metanephridien angesehen. Neuere Untersuchungen konnten jedoch auch stark reduzierte Metanephridien und Protonephridien als Segmentalorgane in diesem Polychaetentaxon nachweisen. Im Rahmen der vorliegenden Dissertation wurden die Segmentalorgane der Syllidae ultrastrukturell untersucht, um Hinweise auf die Verwandtschaftsverhältnisse der vier Unterfamilien zu erhalten, und um eine sekundäre Entstehung von Protonephridien aus Metanephriden innerhalb der Syllidae nachzuweisen. Für weitere Rückschlüsse auf die Verwandtschaftsverhältnisse innerhalb der Syllidae wurden neben den Segmentalorganen auch Spermien und Brutpflegestrukturen ultrastrukturell bearbeitet. Die Untersuchungen wurden weiterhin für eine Bewertung der systematischen Stellung innerhalb der Phyllodocida genutzt. Insgesamt wurden 21 Segmentalorgane von 18 Taxa der Syllidae und einer Sphaerodoriden-Art untersucht. Spermien und Spermiogenesestadien von fünf Sylliden und die Eianheftungsstrukturen von 11 Syllidentaxa wurden bearbeitet. Mit den in dieser Arbeit präsentierten Daten konnte die sekundäre Entstehung von Protonephridien nachgewiesen werden. Weiterhin wurden wichtige Hinweise für die Verwandtschaftverhältnisse der vier Subtaxa innerhalb der Syllidae geliefert und erstmalig die dorsalen Anheftungsstrukturen brutpflegender Exogoninae detailliert untersucht.

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