This study considers the morphology of the sperm, nephridia, seminal receptacles, and gonads among a number of California spionid species. The data collected provide support for the general observation of other workers.

Orientador: Teodoro Vaske Junior / Resumo: A raia-elétrica N. brasiliensis ocorre do sudeste do Brasil ao norte da Argentina, apresenta de pequeno a médio porte e atinge comprimento máximo de 49 cm. Essas raias são geralmente encontradas em substrato lodoso, composto por areia fina, onde o movimento de protrusão da mandíbula é mais eficiente, facilitando também a sucção das presas. Exemplares de N. brasiliensis são capturados acidentalmente nas regiões sudeste e sul do Brasil, sendo muito suscetíveis às ações antrópicas predatórias. Apesar de ser uma espécie abundante ao longo da costa brasileira, há um conhecimento escasso sobre vários dos seus aspectos biológicos. Estudos relacionados a este gênero concentram-se em distribuição, reprodução, abundância das espécies e em sua dieta, a qual é composta principalmente por crustáceos e anelídeos marinhos, poríferos, equinodermos e sipunculas. O objetivo deste estudo consistiu em analisar o conteúdo estomacal de exemplares de N. brasiliensis, a fim de caracterizar sua dieta na costa sul do Estado de São Paulo, visando obter uma lista de itens alimentares identificados ao menor táxon possível e a proporção geral dos grandes grupos de presas de sua dieta; bem como avaliar a dieta em relação à ontogenia e sazonalidade, além de identificar os principais componentes anatômicos do trato digestório. A dieta de N. brasiliensis na região de estudo foi composta por cinco grandes grupos: Classe Polychaeta, Classe Sipunculida, Ordem Decapoda, Ordem Stomatopoda e Ordem Anguiliformes. Os... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The lesser electric ray N. brasiliensis is distributed from southern Brazil to northern Argentina, it is small to medium sized and its maximum lenght is 49 cm. These rays are usually found in muddy sediment, in which the jaws protusion movement is more efficient, making easier the prey suction. Specimens of N. brasiliensis are accidentally caught in the southeastern and southern regions of Brazil, being very susceptible to predatory anthropic actions. Although it is an abundant species along the Brazilian coast, there is no much information about its biological aspects. Studies related to the gender are focused in distribution, reproduction, species abundance and diet, which is mainly composed by crustaceans, polychaetes, poriferous, echinoderms and sipuncula. The objective of this research was to analyse the stomach content of N. brasiliensis specimens, to characterize its diet on the south coast of São Paulo State, aiming to obtain a list of food items identified at the lowest possible rate and the general proportion of the large groups of prey in their diet; as well as evaluating the diet in relation to ontogeny and seasonality, in addition to identify the main anatomical components of the digestive tract. The diet of N. brasiliensis in the study region was composed of five major groups: Class Polychaeta, Class Sipunculidea, Order Decapoda, Order Stomatopoda and Order Anguiliformes. Polychaetes 1, of the Arabellidae Family, were the main food component of this species in t... (Complete abstract click electronic access below) / Mestre

There are no published accounts of larval development for P. giardi, although Mesnil (1896) determined his populations to be simultaneous hermaphrodites. The present paper describes aspects of the reproductive biology and larval development of P. girardi and presents descriptions and illustrations of developing larvae and recently metamorphosed juveniles.

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published_or_final_version / Biological Sciences / Doctoral / Doctor of Philosophy

Serpulidae Rafinesque, 1815 é uma das famílias de poliquetas mais facilmente reconhecíveis, por viverem em tubos calcários e possuírem o corpo dividido em três regiões bem definidas, coroa branquial, tórax e abdômen, geralmente com um opérculo, que fecha a abertura do tubo quando a coroa branquial é retraída, e uma membrana torácica, que é um prolongamento do colar, estendendo-se ao longo do tórax dorsalmente por número variável de setígeros. São muito abundantes no litoral brasileiro e importantes na comunidade incrustante, que reveste pedras, algas e demais estruturas que forneçam o substrato adequado para a instalação destes animais, sendo um dos principais grupos de poliquetas em estudos de bioinvasão. Ao longo da história taxonômica da família, as relações filogenéticas e a classificação sistemática do grupo passaram por diversas alterações e atualmente, com base em estudos morfológicos e moleculares, são considerados como grupo irmão de Fabriciidae Rioja, 1923, e o clado, grupo-irmão de Sabellidae Latreille, 1825. O presente trabalho é um dos primeiros estudos de cunho taxonômico tratando especificamente da Família Serpulidae ao longo da costa brasileira, com o objetivo de identificar e descrever as espécies destes animais encontradas entre as regiões Sul-Nordeste do país; foram analisados 443 indivíduos, pertencentes a dez gêneros e 16 espécies, uma das quais é nova ocorrência para o Brasil e outra é nova para a ciência / Serpulidae Rafinesque, 1815 is one of the most easily recognizable families of polychaetes, because these animals live in calcareous tubes and have the body divided into three well-defined regions, the branchial crown, thorax and abdomen, usually with an operculum, which closes the mouth of the tube when the branchial crown is retracted, and a thoracic membrane, which is an extension of the collar dorsally, extending along the thorax for a variable number of chaetigers. Serpulids are very abundant in Brazil and important in the fouling community, coating rocks, algae and other structures which provide the appropriate substrate for the installation of these animals, being one of the major groups of polychaetes in bioinvasion studies. Our understanding on the phylogenetic relationships within Serpulidae and between the family and the closely related Fabriciidae Rioja, 1923 and Sabellidae Latreille, 1825 has changed through time; currently, based on both morphological and molecular studies, serpulids are regarded as the sister group of Fabriciidae and this clade is sister to Sabellidae. The present study is one of the first taxonomic studies dealing specifically with the Family Serpulidae along the Brazilian coast, aiming to identify and describe the species found between the southern and northeastern regions; 443 specimens were analyzed, belonging to ten genera and 16 species, of which one species is firstly reported for Brazilian waters and another is new to science

South Australian mangroves consist of only one single species Avicennia marina (Fosk.) Vierh.var australasica (Walp) Moldenke, 1960. They are distributed discontinuously within St. Vincent Gulf and Spencer Gulf and provide significant valuable habitat both in economical and ecological terms. The Fisheries Act 1971-1982 protected the existence of mangroves and the Harbour Act 1936-1981 controlled removal of mangrove areas in coastal development. To date very few ecological studies have been conducted in the South Australian mangroves, particularly on the infaunal organisms that have an important role in maintaining the ecological dynamic within the estuaries systems. As this is the first study on infaunal mangrove communities in the inverse estuaries of South Australia, there was no prior data for ecological comparison. The study was conducted at three mangroves location (Garden Island, Middle Beach and Saint Kilda) close to Adelaide in May 2000 and 2001. Overall the study has reported that the infaunal mangrove assemblages of South Australian mangroves were comparable to other temperate mangroves. The infaunal communities were characterised by lower diversity and abundance compared to the tropical or subtropical mangroves. The infaunal zonation related to the tidal gradient and habitat variation was detected. Most infauna organisms occupied the surface layers and substantially decreased towards the deeper layers. The study also suggested that sediment structure of mangrove systems were complex and infaunal communities responded differently to the change of environmental conditions both in small scale and larger scale. Thus, assessing the infaunal communities structure in mangrove systems should be based on ecological characteristics rather than geographical positions. The examination of dominant polychaetes families showed that different species have different responses to the environmental cues within mangrove systems. The study did not find that any polychaete species was restricted to mangroves only as they all were also found in the habitat adjacent mangrove forest. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2003.

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