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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.
11

Life history, production, and food resources of the deposit-feeding polychaete Euzonus mucronata (Treadwell) on an Oregon coastal sand beach

Kemp, P. F. 30 April 1985 (has links)
Graduation date: 1985
12

The swimming response of the Sacconereis stage of Autolytus varius to changes in hydrostatic pressure

Smith, Randall William 09 May 1969 (has links)
The syllid polychaete Autolytus varius reproduces in the spring and early summer in Yaquina Bay, Oregon, The fertilized female epitokes, or Sacconereis, carry the developing eggs and larvae in a ventral sac until the larvae are ready to be released; incubation lasts 14 to 18 days in the laboratory, The effects of a small increase in hydrostatic pressure on the activity of Sacconereis were tested, When placed in a pressure vessel, these epitokes responded to increases of 0.39 Bar by orienting dorsally and swimming upward, and by increasing their swimming rate, Peak activity occurred in the first minute after a pressure stimulus. Following this, there was a period of accommodation until the epitokes returned close to their normal level of activity; the period of accomodation lasted around 11 minutes, When the pressure was released, the worms either slowed their swimming rate, or they coiled and sank rapidly to the bottom of the vessel. Decerebrate Sacconereis of A. varius did not respond to pressure stimuli. The Sacconereis of A. magnus and A. prismaticus, and the Polybostrichus of A. prismaticus demonstrated swimming responses similar to A. varius Sacconereis. Three other species of polychaetes did not respond to pressure changes. The hydrostatic pressure response is possibly an adaptation of a planktonic stage of a normally benthic animal. / Graduation date: 1969
13

The central nervous system of the polychaete Capitella capitata : adult morphology, larval development and behaviour

Bhup, Rohan. January 1980 (has links)
No description available.
14

Biogenic amines in the central nervous system of the polychaete, Nereis virens

White, Debrah Lynn. January 1976 (has links)
No description available.
15

Systematics and evolution of scale warms (aphroditiformia, polychaeta), with a focus on deep-sea species

Zhang, Yanjie 27 September 2017 (has links)
1.1\xPolychaetes in the suborder Aphroditiformia are commonly called scale worms because they are characterized by having dorsal elytra or scales. Scale worms are a large group of polychaetes and play an important role in marine ecosystems. They are widely distributed in the sea, from the tropics to polar regions, and from the shallow water to the deep sea. Since the first discovery of hydrothermal vents in 1977, many deep-sea scale worms, most of which belong to the largest scale-worm family Polynoidae, have been reported. Yet little is known about the phylogeny and genetic adaptation of deep-sea polynoids to the extreme deep-sea environment. The identification of these scale worms was solely based on morphology. However, the morphological character states for the delimitation of some of these scale worms were ambiguous. In addition, due to the lack of molecular information, phylogenetic relationships among several groups of scale worms are unclear. Thus, the aim of my study was to improve our knowledge about the phylogeny and evolution of Aphroditiformia with a focus on deep-sea polynoids.;1.2\xMy thesis is divided into five chapters. The first chapter is an introduction of the status of polychaete taxonomy, with an emphasis of Aphroditiformia. Among the three experimental chapters, Chapter 2 is a systematics study of deep-sea scale worms collected from the Okinawa Trough. In this chapter, I described four species of polynoids, including a new species of Levensteiniella, a new species of Branchinotogluma, a male morphotype of Lepidonotopodium okinawae, and a female morphotype of Branchinotogluma japonicus. Moreover, a fragment of the COI gene for selected specimens of these species were amplified to determine phylogenetic relationships with other deep-sea polynoids.;1.3\xIn Chapter 3, I applied low-coverage DNA sequencing to obtain 18S, 28S rRNA and mitochondrial genomes from 16 species representing 7 families in Aphroditiformia. Two phylogenetic trees were constructed: the first based on the concatenated sequences of four partial genes (cox1, 16S, 18S and 28S rRNA), and the second using mitochondrial protein-coding genes, rRNA genes and two nuclear rRNA genes (18S and 28S rRNA). The results showed that Aphroditiformia is monophyletic. Eulepethidae and Aphroditidae for the sister group of the other scale-worm families. Acoetidae is sister to Iphionidae. Polynoidae is monophyletic, but within this family, deep-sea subfamilies Branchinotogluminae and Macellicephalinae are paraphyletic. There are two large gene order rearrangements in the mitochondrial genomes of deep-sea polynoids, and substitution rates of mitochondrial protein-coding genes in deep-sea species are much higher than those in shallow-water species, which indicate that the extreme environment in deep sea may have affected the evolution rate and gene order of the mitochondrial genomes of deep-sea polynoids. The large mitochondrial gene order rearrangements have provided evidence to refute the assumption that mitochondrial gene order is conserved in Errantia.;1.4\xIn Chapter 4, I reported two transcriptomes of deep-sea polynoids (Branchipolynoe pettiboneae and Lepidonotopodium okinawae) newly obtained by next generation sequencing, and compared them with the transcriptome of a shallow-water polynoid (Harmothoe imbricata). The results showed that among the highly expressed genes, duplicated genes related to DNA recombination and metabolism were only enriched in the deep-sea species, indicating that the deep-sea species have a more complex DNA repair system which could prevent harmful DNA mutation caused by DNA damage. Compared to the shallow-water polynoid, the deep-sea species have more hemoglobin genes and their expression levels were higher than those of the shallow-water species, indicating high expression of more hemoglobin genes is crucial for deep-sea scale worms to adapt to the hypoxic environment.;1.5\xOverall, my empirical systematics study and molecular phylogenetic study have improved our understanding about the systematics and phylogeny of Aphroditiformia, and my transcriptomic comparison between the deep-sea and shallow-water polynoids has enhanced our understanding about the adaptation of deep-sea scale worms to the extreme environmental conditions in hydrothermal vents and methane seeps.
16

The central nervous system of the polychaete Capitella capitata : adult morphology, larval development and behaviour

Bhup, Rohan. January 1980 (has links)
No description available.
17

Contribuição ao conhecimento taxonômico dos poliquetas Sabelídeos (Polychaeta: Sabellidae) da região Sudeste do Brasil / Contributions to the Taxonomic Knowledge of Sabelid Polychaetes (Polychaeta: Sabellidae) off Southeastern Brazil

Rossi, Maíra Cappellani Silva 27 March 2008 (has links)
O presente estudo consiste num levantamento taxonômico de poliquetas da família Sabellidae coletados da zona entremarés, ao longo da costa do Estado de São Paulo, e águas profundas, nos estados do Rio de Janeiro e São Paulo. O material é proveniente dos projetos \"Biodiversidade de Anelídeos Poliquetas em Costões Rochosos ao Longo do Estado de São Paulo\", BIOTA/FAPESP - Bentos Marinho e REVIZEE/Score Sul - Bentos. Para identificações, descrições e ilustrações dos táxons foram utilizados microscópios estereoscópico, óptico e eletrônico de varredura, além do uso de câmera digital. As espécies estudadas foram: Amphicorina sp. n., Amphiglena lindae, Branchiomma luctuosum, B. patriota, Chone sp. n., Demonax cf. microphthalmus, Euchone sp. n., Fabriciola sp. n., Jasmineira sp. n., Kirkiana heterobranchiata, Manayunkia brasiliensis, Megalomma sp. n., Notaulax nudicollis, Notaulax sp. n. 1, Notaulax sp. n. 2, Potamethus sp. n., Pseudobranchiomma minima, P. paraemersoni, P. paulista, Pseudopotamilla sp. n., P. cf. reniformis, Perkinsiana sp. n. e Sabellomma minuta gen. n. Destas, 14 são espécies novas para a ciência e 2 são novas ocorrências da espécie no litoral brasileiro, além de dois gêneros novos para a ciência, um dos quais, já formalmente descrito. O gênero Sabelloma gen. n. assemelha-se a Bispira, e é caracterizado pela presença de radíolos com ocelos lenticulados como unidades independentes, tórax com 4-5 setígeros, presença de ocelos interramais e de cerdas acompanhantes dos uncini. O gênero Kirkiana assemelha-se a Perkinsiana, possui como principais caracteres colar fundido dorsalmente à goteira fecal, par mais dorsal de radíolos mais curto do que os demais em espécimes férteis, lábios dorsais sem apêndices radiolares e uncini com manúbrios curtos. São fornecidas chaves de identificação, descrições completas e comparações. / The present study is a taxonomic survey of polychaetes from of the family Sabellidae collected from intertidal zone, along the coast off the State of São Paulo, and deep waters, off the states of Rio de Janeiro and São Paulo. The material came from the projects \"Biodiversity of Intertidal Polychaetes (Annelida: Polychaeta) on Rocky Shores off the State of São Paulo, Brazil\", BIOTA/FAPESP/Benthic Marine Biodiversity and REVIZEE/South Score - Benthos. Identifications, descriptions and illustrations were made with stereomicroscope, optic and scanning electronic microscope, besides the use of digital camera. The species studied were: Amphicorina sp. n., Amphiglena lindae, Branchiomma luctuosum, B. patriota, Chone sp. n., Demonax cf. microphthalmus, Euchone sp. n., Fabriciola sp. n., Jasmineira sp. n., Kirkiana heterobranchiata, Manayunkia brasiliensis, Megalomma sp. n., Notaulax nudicollis, Notaulax sp. n. 1, Notaulax sp. n. 2, Potamethus sp. n., Pseudobranchiomma minima, P. paraemersoni, P. paulista, Pseudopotamilla sp. n., P. cf. reniformis, Perkinsiana sp. n. e Sabellomma minuta gen. n. From these, 14 are species new to science and 2 are new occurrences to Brazilian coast, besides 2 new genera, one of which already formally described. The genus Sabellomma gen. n. is similar to Bispira, and it is characterized by the presence of unpaired, irregularly-spaced radiolar eye spots, thorax with 4-5 chaetigers, presence of interramal eyespots and companion chaetae. The genus Kirkiana is similar to Perkinsiana,, and its main diagnostic characters are collar dorsally fused to the fecal groove, dorsalmost pair of radioles shorter than the remaining ones in fertile specimens, dorsal lips lacking radiolar appendages and uncini with short handles. Identification keys, complete descriptions and comparisons with closest congeners are provided.
18

Diversidade dos silídeos (Annelida: Phyllodocida: Syllidae) associados ao fital no litoral de São Sebastião - SP / Diversity of Syllidae (Annelida: Phyllodocida) associated to the fital in São Sebastião coast - SP

De Chiara, Felipe Ramon Podadera 21 September 2017 (has links)
A família Syllidae, apesar de ser uma das mais diversas e abundantes dentre os poliquetas, possui apenas cerca de 140 espécies registradas no litoral brasileiro, o que é pouco, considerando-se a extensão da nossa costa e o número de espécies encontradas em locais onde a família já foi melhor analisada. O presente estudo tem como objetivo analisar taxonomicamente os silídeos de um ambiente em que foram pouco estudados no Brasil, até o momento, o fital. A área de estudo foi composta por algumas praias de São Sebastião, litoral norte de São Paulo. Além da caracterização taxonômica das espécies encontradas, foram identificados padrões de associações específicas entre determinadas espécies de algas e alguns silídeos, algumas dessas relações já conhecidas em certas localidades, mas poucas vezes relatadas para o Brasil. Foram encontradas 1 nova ocorrência para a costa brasileira, e 4 espécies novas para a ciência / The family Syllidae, in spite of being among the most diverse and abundant groups of polychaetes, has only about 140 species registered for off the Brazilian coast, which is a low number, considering the extension of our coast and the number of species found in places where the syllids have been more thoroughly analyzed. The present study is a taxonomic survey on the syllids occurring on an environment which has been rarely studied in Brazil so far, the phytal. The study was carried out off some beaches off São Sebastião, on the northern coast of the state of São Paulo. In addition to the characterization of the species found, some patterns of specific associations between certain species of algae and some syllids have been observed, some of those relationships are already known for certain localities around the world, but were rarely reported for the Brazilian coast. Among all the species analyzed, one new occurrence off the Brazilian coast and four species new to science were found
19

Contribuição ao conhecimento taxonômico dos silídeos (Polychaeta: Syllidae) da região sudeste-sul do Brasil / Contribution to the taxonomic knowledge of the syllids (Polychaeta: Syllidae) from southeastern-southern Brazil

Fukuda, Marcelo Veronesi 10 May 2010 (has links)
Syllidae Grube, 1850 é uma das maiores famílias de poliquetas, caracterizada por apresentar animais errantes de corpos relativamente pequenos, com segmentação homônoma e parapódios unirremes internamente sustentados por acículas, excepcionalmente adquirindo condição birreme nas formas epítocas; associado à porção posterior da faringe, o proventrículo, estrutura muscular em forma de barril que pode ser facilmente visualizado por transparência através da superfície do corpo, é uma das sinapomorfias da família. O grupo destaca-se pela variedade de estratégias reprodutivas, com representantes apresentando, em geral, o fenômeno da epitoquia, mas também sendo encontradas incubação externa de ovos, viviparidade, partenogênese e arquitomia. Syllidae conta atualmente com 5 subfamílias, Syllinae Grube, 1850, Autolytinae Langerhans, 1879, Exogoninae Langerhans, 1879, Eusyllinae Malaquin, 1893, e Anoplosyllinae Aguado & San Martín, 2009, divididas de acordo com a morfologia dos palpos, antenas, cirros peristomiais e cirros dorsais ao longo do corpo, além do formato da faringe e proventrículo. Apesar de ser uma das famílias mais abundantes e diversificadas dentre todos os Polychaeta, o estado do conhecimento da fauna de silídeos ocorrendo ao longo do litoral brasileiro ainda é bastante pobre. Até o momento, foram registrados apenas 25 gêneros e 84 espécies para a costa brasileira, o que é relativamente pouco em comparação com outras regiões onde a fauna de silídeos é melhor conhecida, como a Península Ibérica, por exemplo. A presente Tese consiste em um estudo taxonômico dos Syllidae da região sudeste/sul do Brasil, a partir de material coletado por três projetos independentes: REVIZEE/Score Sul/Bentos Marinho, BIOTA/FAPESP/Biodiversidade Bêntica Marinha no Estado de São Paulo, e Biodiversidade de Anelídeos Poliquetas em Costões Rochosos ao Longo do Estado de São Paulo. As identificações foram feitas com base em caracteres morfológicos, utilizando microscópio óptico e, em alguns casos, microscópio eletrônico de varredura (MEV), com o auxílio de bibliografia especializada e atualizada. No caso de algumas espécies, foram feitas comparações com material-tipo e espécimes coletados em outras localidades. Para as ilustrações, foram utilizadas câmaras-clara e fotográfica digital acopladas ao microscópio óptico, além de MEV. Neste estudo, foram analisados 10299 espécimes, pertencentes a 24 gêneros e 83 espécies, das quais 40 táxons são novas ocorrências para a costa brasileira e 15 tratam-se de espécies novas para a ciência. / Syllidae Grube, 1850, is one of the largest polychaete families, comprehending relatively small-bodied errant animals, with homonomous segmentation and uniramous parapodia internally sustained by aciculae, exceptionally biramous in epitokous forms; located at the posterior part of the pharynx, the proventricle, a barrel-shaped muscular structure easily seen by transparency through the body wall, is one of the synapomorphies of the family. The group is notorious by the diversity of reproductive strategies, with representatives usually presenting the phenomena of epitoky, but external brooding of eggs, viviparity, parthenogenesis and architomy are all also found among syllids. Syllidae currently consists on 5 sub-families, Syllinae Grube, 1850, Autolytinae Langerhans, 1879, Exogoninae Langerhans, 1879, Eusyllinae Malaquin, 1893, and Anoplosyllinae Aguado & San Martín, 2009, defined by the morphology of the palps, antennae, peristomial and dorsal cirri, and by the shape of the pharynx and proventricle. Despite being one of the most abundant and diverse families of Polychaeta, the state of knowledge of the syllid fauna occurring off the Brazilian coast is still poor. Up to the present, only 25 genera and 84 species have been registered for the area, which is a relatively low number compared to regions where the syllid fauna has been more extensively investigated, as the Iberian Peninsula, for example. The present Thesis is a taxonomic study of the Syllidae from the southeasternsouthern coast off Brazil, based on material collected by three independent projects: REVIZEE/Score Sul/Bentos Marinho, BIOTA/FAPESP/Benthic Marine Biodiversity in the State of São Paulo, and Biodiversity of Intertidal Polychaetes (Annelida: Polychaeta) on Rocky Shores off the State of São Paulo. Identifications were based on morphological characters seen under compound light microscope and, in some cases, scanning electron microscope (SEM), with the aid of specialized and updated scientific literature. For some species, comparisons were made with type-material and specimens from other localities. Illustrations were done with the aid of drawing tubes and/or digital camera attached to the microscope, in addition to the SEM images, when available. Material examined consists of 10299 specimens, belonging to 24 genera and 83 species, of which 40 taxa are new occurrences for the Brazilian coast, and 15 species are new to science.
20

Investigation of genes involved in larval attachment and metamorphosis of biofouling species hydroides elegans and balanus amphitrite /

Li, Honglei. January 2007 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Ph.D. in Marine Environmental Science. Includes bibliographical references. Also available in electronic version.

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