Thesis (Ph. D.)--University of Rhode Island, 2003. / Typescript. Includes bibliographical references (leaves 191-207).

Staurozoa é uma das cinco classes atuais do filo Cnidaria. Nesta tese, propomos um estudo integrado da evolução de Staurozoa englobando dados moleculares, morfológicos e de cnidoma. Visando abordar estes diferentes aspectos, este projeto teve como objetivos inferir (1) o relacionamento evolutivo entre as espécies de Staurozoa; (2) a evolução do plano corporal de Staurozoa; e (3) o significado taxonômico/evolutivo do cnidoma para classe. O capítulo \"Global diversity and phylogenetic systematics of stalked jellyfishes (Cnidaria: Staurozoa)\" propõe uma hipótese filogenética para representantes da classe Staurozoa. Esta hipótese balizou uma extensa revisão da classificação do grupo. O estudo apresenta ainda uma revisão histórica da classe, incluindo dados de taxonomia, diversidade, distribuição geográfica e batimétrica, uso do substrato, alimentação, comportamento, ciclo de vida e conservação. No capítulo \"Evolution of the body plan in Staurozoa (Cnidaria): a comparative histological study\", a anatomia interna de 10 espécies foi analisada evolutivamente com base na nossa proposta filogenética molecular para a classe. Caracteres pouco estudados para o grupo foram detalhados de forma comparativa e suas possíveis funções discutidas. A evolução dos nematocistos em Staurozoa é analisada no capítulo \"Phylogenetic signal of nematocysts in Staurozoa (Cnidaria)\". Dados de 17 espécies foram analisados com base em nossa hipótese filogenética. Por meio de dados de morfometria tradicional e geométrica, concluímos que há um sinal filogenético significativo nos nematocistos dos tentáculos secundários, o que não ocorre no tipo de nematocisto encontrado nas baterias subumbrelares. A possível relação entre o sinal filogenético e o desenvolvimento dos nematocistos em Staurozoa é discutida, assim como possíveis pressões evolutivas envolvidas na presença e ausência de sinal filogenético / Staurozoa is one of the five current classes of the phylum Cnidaria. In this Dissertation we propose an integrative study of the evolution of Staurozoa, encompassing molecular, morphology, and cnidome information. In order to address these different aspects, the general aims of this project are to infer (1) the evolutionary relationship between species of Staurozoa; (2) the evolution of the body plan in Staurozoa; and (3) the taxonomic and evolutionary meaning of cnidome for the class. The chapter \"Global diversity and phylogenetic systematics of stalked jellyfishes (Cnidaria: Staurozoa)\" presents a comprehensive phylogenetic hypothesis for representatives of the class Staurozoa. This hypothesis supported an extensive reassessment of staurozoan classification. The study also presents an historical review of the class, including information on taxonomy, diversity, geographical and bathymetric distribution, use of substrate, feeding, behavior, life cycle, and conservation. In the chapter \"Evolution of the body plan in Staurozoa (Cnidaria): a comparative histological study\", the internal anatomy of 10 species was evolutionarily analyzed based on our molecular phylogenetic hypothesis for the class. Characters rarely studied for the group were comparatively described in detail, and their possible functions were discussed. The evolution of nematocysts in Staurozoa is analyzed in the chapter \"Phylogenetic signal of nematocysts in Staurozoa (Cnidaria)\". Data from 17 species were analyzed based on our phylogenetic hypothesis. Using traditional and geometric morphometric data, we concluded that there is a significant phylogenetic signal for the nematocysts from secondary tentacles, which was not observed for the nematocysts from white spots. The possible relationship of phylogenetic signal and development of nematocysts in Staurozoa is discussed, as well as the possible evolutionary pressures involved in the presence and absence of phylogenetic signal

Staurozoa é uma das cinco classes atuais do filo Cnidaria. Nesta tese, propomos um estudo integrado da evolução de Staurozoa englobando dados moleculares, morfológicos e de cnidoma. Visando abordar estes diferentes aspectos, este projeto teve como objetivos inferir (1) o relacionamento evolutivo entre as espécies de Staurozoa; (2) a evolução do plano corporal de Staurozoa; e (3) o significado taxonômico/evolutivo do cnidoma para classe. O capítulo \"Global diversity and phylogenetic systematics of stalked jellyfishes (Cnidaria: Staurozoa)\" propõe uma hipótese filogenética para representantes da classe Staurozoa. Esta hipótese balizou uma extensa revisão da classificação do grupo. O estudo apresenta ainda uma revisão histórica da classe, incluindo dados de taxonomia, diversidade, distribuição geográfica e batimétrica, uso do substrato, alimentação, comportamento, ciclo de vida e conservação. No capítulo \"Evolution of the body plan in Staurozoa (Cnidaria): a comparative histological study\", a anatomia interna de 10 espécies foi analisada evolutivamente com base na nossa proposta filogenética molecular para a classe. Caracteres pouco estudados para o grupo foram detalhados de forma comparativa e suas possíveis funções discutidas. A evolução dos nematocistos em Staurozoa é analisada no capítulo \"Phylogenetic signal of nematocysts in Staurozoa (Cnidaria)\". Dados de 17 espécies foram analisados com base em nossa hipótese filogenética. Por meio de dados de morfometria tradicional e geométrica, concluímos que há um sinal filogenético significativo nos nematocistos dos tentáculos secundários, o que não ocorre no tipo de nematocisto encontrado nas baterias subumbrelares. A possível relação entre o sinal filogenético e o desenvolvimento dos nematocistos em Staurozoa é discutida, assim como possíveis pressões evolutivas envolvidas na presença e ausência de sinal filogenético / Staurozoa is one of the five current classes of the phylum Cnidaria. In this Dissertation we propose an integrative study of the evolution of Staurozoa, encompassing molecular, morphology, and cnidome information. In order to address these different aspects, the general aims of this project are to infer (1) the evolutionary relationship between species of Staurozoa; (2) the evolution of the body plan in Staurozoa; and (3) the taxonomic and evolutionary meaning of cnidome for the class. The chapter \"Global diversity and phylogenetic systematics of stalked jellyfishes (Cnidaria: Staurozoa)\" presents a comprehensive phylogenetic hypothesis for representatives of the class Staurozoa. This hypothesis supported an extensive reassessment of staurozoan classification. The study also presents an historical review of the class, including information on taxonomy, diversity, geographical and bathymetric distribution, use of substrate, feeding, behavior, life cycle, and conservation. In the chapter \"Evolution of the body plan in Staurozoa (Cnidaria): a comparative histological study\", the internal anatomy of 10 species was evolutionarily analyzed based on our molecular phylogenetic hypothesis for the class. Characters rarely studied for the group were comparatively described in detail, and their possible functions were discussed. The evolution of nematocysts in Staurozoa is analyzed in the chapter \"Phylogenetic signal of nematocysts in Staurozoa (Cnidaria)\". Data from 17 species were analyzed based on our phylogenetic hypothesis. Using traditional and geometric morphometric data, we concluded that there is a significant phylogenetic signal for the nematocysts from secondary tentacles, which was not observed for the nematocysts from white spots. The possible relationship of phylogenetic signal and development of nematocysts in Staurozoa is discussed, as well as the possible evolutionary pressures involved in the presence and absence of phylogenetic signal

Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / Historically, two species of Chrysaora are known from the Benguela Current Ecosystem: C.fulgida (Reynaud 1830) and C. africana (Vanhöffen 1902). However a third morphotype is now seen, which bears a resemblance to both. Thus a complete qualitative and quantitative analysis of the morphometric and meristic data of these three species was conducted, along with an in depth study into the cnidome as a potential tool of identification. These findings are supplemented by a genetic analysis using cytochrome c oxidase subunit I and internal transcribed spacer 1 gene markers. Three species were unambiguously identified. The genetics and morphology showed considerable divergence, with some of the features used to separate them including: tentacle number and shape, colouration and shape of the oral arm, shape of the gastrovascular pouches and the number and shape of the marginal lappets. Although the mtDNA indicated clear separation of the three Chrysaora, the nucDNA displayed some ambiguity. The cnidome showed considerable divergence and succeeded in separating these species, while the rhopalia of the three species also showed distinct differences in the lengths of the rhopalal canals and basal stems. Much of the confusion surrounding jellyfish taxonomy has been the result of observations made on predominantly preserved specimens that are in subpar quality, a hinderence which this study endeavored to overcome. / National Research Foundation (NRF)

The sea anemone Aiptasia pallida is a biological model for anthozoan research. Like all cnidarians, A. pallida possesses nematocysts for food capture and defense. Studies have shown that anthozoans, such as corals, can rapidly increase nematocyst concentration when faced with competition or predation, suggesting that nematocyst production may be an induced trait. The potential effects of two types of tissue damage, predator induced (Lysmata wurdemanni) and artificial (forceps), on nematocyst concentration was assessed. Nematocysts were identified by type and size to examine the potential plasticity associated with nematocyst production. While no significant differences were found in defensive nematocyst concentration between shrimp predation treatments versus controls, there was a significant difference in small-sized nematocyst in anemones damaged with forceps. The proportions of the different types of nematocysts between treatment types were also found to be different suggesting that nematocyst production in A. pallida is a plastic trait. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

No description available.

No description available.

Os ciclos de vida de Clytia linearis (Thornely, 1899) e de duas espécies apresentando caracteres considerados diagnósticos de Clytia gracilis (M. Sars, 1850) – aqui denominadas Clytia cf. gracilis sp. 1 e Clytia cf. gracilis sp. 2 – foram estudados com base em espécimes coletados no infralitoral raso da costa de São Sebastião e Ilhabela, sudeste do Brasil, entre fevereiro de 1999 e abril de 2000. Medusas foram cultivadas em laboratório, a temperatura de 22-24oC. Colônias de C. linearis são monossifônicas, simpodiais, com até 21,5mm de altura e portando até 26 hidrantes e 10 gonângios. Medusas adultas, alcançando 2,5-3,6mm de diâmetro e até 29 tentáculos e 28 estatocistos, podem ser distinguidas de outras espécies de Clytia pela presença de nematocistos microbásicos mastigóforos do tipo C. Medusas adultas de Clytia cf. gracilis spp. 1 e 2 podem ser distinguidas das demais espécies do gênero estudadas até o momento pela presença de uma fileira de nematocistos microbásicos mastigóforos do tipo A na umbrela, no nível do canal circular. Medusas adultas de C. cf. gracilis sp. 1 e C. cf. gracilis sp. 2 apresentam até 16 tentáculos e podem ser distinguidas entre si pelo diâmetro da umbrela: 6,6-10,1mm e 3,6-5,5mm, respectivamente. Quanto ao estágio de pólipo, C. cf. gracilis sp. 1 apresenta usualmente colônias dicotômicas eretas, hidrotecas alongadas, e gonotecas na hidrorriza e pedículos. Estes caracteres concordam com a descrição de C. gracilis, mas as espécies diferem entre si pela morfometria das gonotecas e dos nematocistos microbásicos mastigóforos do tipo B: aproximadamente 15mm de comprimento para C. gracilis e 9-10mm para C. cf. gracilis sp. 1. Por outro lado, nematocistos do tipo B de C. cf. gracilis sp. 2, com aproximadamente 14,5mm de comprimento, em média, são morfometricamente semelhantes aos de C. gracilis. No entanto, C. cf. gracilis sp. 2 difere de C. gracilis pela forma da hidroteca, por apresentar gonotecas apenas na hidrorriza, e pelo hábito polissifônico do colônias bem desenvolvidas. Uma terceira espécie, C. cf. gracilis sp. 3, é descrita com base em uma colônia sem gonângios. Aspectos da sistemática de Clytia são discutidos. / he life-cycles of Clytia linearis (Thornely, 1899) and two species with characters considered diagnostic of Clytia gracilis (M. Sars, 1850) – Clytia cf. gracilis sp. 1 and Clytia cf. gracilis sp. 2 – have been studied based on specimens collected in the shallow subtidal coast of São Sebastião and Ilhabela, southeast Brazil, between February 1999 and April 2000. Medusae were cultured in the laboratory (22-24oC). Colonies of C. linearis are monosiphonic, sympodial, up to 21.5mm high and bearing up to 26 hydranths and 10 gonangia. Adult medusae reached 2.5-3.6mm in diameter, and up to 29 tentacles and 28 statocysts. The presence of microbasic mastigophore type C nematocysts distinguishes adult medusae of C. linearis from other species of Clytia. A band of microbasic mastigophore type A nematocysts in the umbrella, at the level of the circular canal, distinguishes adult medusae of Clytia cf. gracilis spp. 1 and 2 from other species of the genus. Adult medusae of C. cf. gracilis sp. 1 and C. cf. gracilis sp. 2 have up to 16 tentacles, and can be distinguished by the diameter of the umbrella: 6.6-10.1mm and 3.6-5.5mm, respectively. Colonies of C. cf. gracilis sp. 1 are usually erect and dichotomous, the hydrothecae are elongated and the gonothecae present in the hydrorhiza and pedicels. These features closely match with the description of C. gracilis, but both species differ in the morphometry of the gonothecae and microbasic mastigophore type B nematocysts: about 15mm (length) for C. gracilis and 9-10mm for C. cf. gracilis sp. 1. Type B nematocysts of C. cf. gracilis sp. 2 (about 14.5mm in length) are more similar in size to those of C. gracilis. However, the former species differs from the latter in the shape of the hydrothecae, by having gonothecae only at the hydrorhiza and polysiphonic well-developed colonies. A third species, C. cf. gracilis sp. 3, is described based on an unfertile colony. Aspects of the systematics of Clytia are discussed.

Os ciclos de vida de Clytia linearis (Thornely, 1899) e de duas espécies apresentando caracteres considerados diagnósticos de Clytia gracilis (M. Sars, 1850) – aqui denominadas Clytia cf. gracilis sp. 1 e Clytia cf. gracilis sp. 2 – foram estudados com base em espécimes coletados no infralitoral raso da costa de São Sebastião e Ilhabela, sudeste do Brasil, entre fevereiro de 1999 e abril de 2000. Medusas foram cultivadas em laboratório, a temperatura de 22-24oC. Colônias de C. linearis são monossifônicas, simpodiais, com até 21,5mm de altura e portando até 26 hidrantes e 10 gonângios. Medusas adultas, alcançando 2,5-3,6mm de diâmetro e até 29 tentáculos e 28 estatocistos, podem ser distinguidas de outras espécies de Clytia pela presença de nematocistos microbásicos mastigóforos do tipo C. Medusas adultas de Clytia cf. gracilis spp. 1 e 2 podem ser distinguidas das demais espécies do gênero estudadas até o momento pela presença de uma fileira de nematocistos microbásicos mastigóforos do tipo A na umbrela, no nível do canal circular. Medusas adultas de C. cf. gracilis sp. 1 e C. cf. gracilis sp. 2 apresentam até 16 tentáculos e podem ser distinguidas entre si pelo diâmetro da umbrela: 6,6-10,1mm e 3,6-5,5mm, respectivamente. Quanto ao estágio de pólipo, C. cf. gracilis sp. 1 apresenta usualmente colônias dicotômicas eretas, hidrotecas alongadas, e gonotecas na hidrorriza e pedículos. Estes caracteres concordam com a descrição de C. gracilis, mas as espécies diferem entre si pela morfometria das gonotecas e dos nematocistos microbásicos mastigóforos do tipo B: aproximadamente 15mm de comprimento para C. gracilis e 9-10mm para C. cf. gracilis sp. 1. Por outro lado, nematocistos do tipo B de C. cf. gracilis sp. 2, com aproximadamente 14,5mm de comprimento, em média, são morfometricamente semelhantes aos de C. gracilis. No entanto, C. cf. gracilis sp. 2 difere de C. gracilis pela forma da hidroteca, por apresentar gonotecas apenas na hidrorriza, e pelo hábito polissifônico do colônias bem desenvolvidas. Uma terceira espécie, C. cf. gracilis sp. 3, é descrita com base em uma colônia sem gonângios. Aspectos da sistemática de Clytia são discutidos. / he life-cycles of Clytia linearis (Thornely, 1899) and two species with characters considered diagnostic of Clytia gracilis (M. Sars, 1850) – Clytia cf. gracilis sp. 1 and Clytia cf. gracilis sp. 2 – have been studied based on specimens collected in the shallow subtidal coast of São Sebastião and Ilhabela, southeast Brazil, between February 1999 and April 2000. Medusae were cultured in the laboratory (22-24oC). Colonies of C. linearis are monosiphonic, sympodial, up to 21.5mm high and bearing up to 26 hydranths and 10 gonangia. Adult medusae reached 2.5-3.6mm in diameter, and up to 29 tentacles and 28 statocysts. The presence of microbasic mastigophore type C nematocysts distinguishes adult medusae of C. linearis from other species of Clytia. A band of microbasic mastigophore type A nematocysts in the umbrella, at the level of the circular canal, distinguishes adult medusae of Clytia cf. gracilis spp. 1 and 2 from other species of the genus. Adult medusae of C. cf. gracilis sp. 1 and C. cf. gracilis sp. 2 have up to 16 tentacles, and can be distinguished by the diameter of the umbrella: 6.6-10.1mm and 3.6-5.5mm, respectively. Colonies of C. cf. gracilis sp. 1 are usually erect and dichotomous, the hydrothecae are elongated and the gonothecae present in the hydrorhiza and pedicels. These features closely match with the description of C. gracilis, but both species differ in the morphometry of the gonothecae and microbasic mastigophore type B nematocysts: about 15mm (length) for C. gracilis and 9-10mm for C. cf. gracilis sp. 1. Type B nematocysts of C. cf. gracilis sp. 2 (about 14.5mm in length) are more similar in size to those of C. gracilis. However, the former species differs from the latter in the shape of the hydrothecae, by having gonothecae only at the hydrorhiza and polysiphonic well-developed colonies. A third species, C. cf. gracilis sp. 3, is described based on an unfertile colony. Aspects of the systematics of Clytia are discussed.