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Relações alométricas da Anomalocardia brasiliana (Gmelin, 1791) na praia de Mangue Seco, Pernambuco-BrasilSOUZA, André Batista de 02 February 2011 (has links)
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Previous issue date: 2011-02-02 / Anomalocardia brasiliana is one of the most common bivalve marine mollusks found in Pernambuco, in the Northeast of Brazil. This shellfish is mainly found on the northern coast of the region, where hand fishing has always been a traditional activity. The aim of the present study was to assess the allometric ratios of growth and weight of the shellfish A. brasiliana, on Mangue Seco beach, in northern Pernambuco. Non-linear regression was performed (Gauss Newton methodology) to investigate if the shellfish exhibited positive, negative or isometric allometry using the following measurements: length/width; length/height; width/height; weight of the shell/soft tissue weight and length/weight (total, shell and soft tissue). Analysis of A. brasiliana confirmed that the length/width ratio was positively allometric whereas all other ratios were negative. The results of the present study may be used in the preparation of management plans for fishing and mariculture development and as a basis to diagnose possible effects caused by environmental changes. / A Anomalocardia brasiliana está entre os moluscos bivalves marinhos mais coletados em Pernambuco, região nordeste do Brasil, esse marisco é naturalmente encontrado principalmente no litoral norte, onde a pesca artesanal sempre foi uma atividade tradicional. O presente estudo teve como objetivo avaliar as relações alométricas no crescimento e peso do marisco A. brasiliana, na praia de Mangue Seco, litoral norte de Pernambuco. Para verificar se o marisco apresentou alometria positiva, negativa ou isometria, foram realizadas regressões não lineares (metodologia Gauss Newton) entre as medidas comprimento/largura, comprimento/altura, largura/altura, peso da concha/peso partes moles e comprimento/peso (total, concha e parte mole). Ao realizar as análises da A. brasiliana verificou-se que a relação comprimento/largura foi alométrico positivo e as demais relações foram negativas. Os resultados desse estudo podem ser utilizados na elaboração de planos de manejo para o desenvolvimento da pesca e maricultura e servir como base para diagnosticar efeitos ocasionados por possíveis alterações ambientais.
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Evolution of Bivalvia: Multi-level phylogenetic and phylogenomic reconstructions within Bivalvia (Mollusca) with emphasis on resolving familial relationships within Archiheterodonta (Bivalvia: Heterodonta).Gonzalez, Vanessa Liz 10 October 2014 (has links)
With an estimated 8,000-20,000 species, bivalves represent the second largest living class of molluscs (Bieler et al. 2013). Revived interest in molluscan phylogeny has resulted in a torrent of molecular sequence data from phylogenetic, mitogenomic, and phylogenomic studies. Despite recent progress, basal relationships of the class Bivalvia remain contentious, owing to conflicting hypotheses often between morphology and molecules.
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Ανάλυση και ταξινόμηση απολιθωμάτων στην περιοχή Καστρίτσι ΑχαΐαςΓκοζντάρης, Αθανάσιος 05 March 2015 (has links)
Στην παρούσα διπλωματική εργασία θα παρουσιαστούν τα αποτελέσματα από τα μάκρο- απολιθώματα που βρέθηκαν και συλλέχθηκαν στην ευρύτερη περιοχή του Καστριτσίου. Η περιοχή του Καστριτσίου ανήκει στην υπο-λεκάνη του Ρίου που αυτή με την σειρά της ανήκει στην λεκάνη του Κορινθιακού (Kontopoulos, N. Zelilidis, A 1997 ). Η Ιζηματολογική ανάλυση της περιοχής μα έχει δείξει ότι έχουν αποτεθεί εναλλαγές λιμνοθαλάσσιων ιζημάτων και αλουβιακών ριπιδίων από το Ανώτερο Πλειόκαινο έως το Ανώτερο Πλειστόκαινο. Τα δείγματα εφόσον εντοπίσθηκαν, μεταφέρθηκαν στο εργαστήριο αρχικά για καθαρισμό και έπειτα μελετήθηκαν για να ταξινομηθούν με βάση τα χαρακτηριστικά τους. Τα δείγματα μας ανήκουν στην συνομοταξία των Μαλάκιων και διαχωρίστηκαν σε τρείς κύριες ομοταξίες των Διθύρων, των Γαστερόποδων και των Σκαφόποδων. Η λεπτομερής μελέτη των δειγμάτων μας έδειξε τα γένη τα οποία βρήκαμε και αναφέρουμε εν συνεχεία ονομαστικά: Cerastoderma edule, Ostrea edulis, Bittium reticulatum, Turritella communis, Nassarius reticulates, Antalis inaequicostata, Antalis vulgaris, Chama gryphoides, Aporrhais pespelecani. Τα Μαλάκια μας έδωσαν πληροφορίες για την θερμοκρασία, την αλατότητα, για το βάθος της περιοχής καθώς και για τα ιζήματα στα οποία αναπτύχθηκαν οι οργανισμοί κατά το Πλειστόκαινο. / -
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Bivalves permianos da fase de continentalização das bacias do Gondwana Ocidental: sistemática, paleogeografia e bioestratigrafiaDavid, Juliana Machado [UNESP] 19 November 2010 (has links) (PDF)
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david_jm_me_rcla.pdf: 2539068 bytes, checksum: 1a12292fb1c96cbb38857041f4625157 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O estudo de bivalves da Formação Gai-As, Permiano, área de Huab, NW da Namíbia, indicou a presença de espécies anteriormente conhecidas apenas no Grupo Passa Dois, Permiano, Bacia do Paraná, Brasil, possibilitando o aprimoramento das correlações estratigráficas entre as duas bacias. A fauna da Formação Gai-As ocorre em intervalos estratigráficos bem definidos, um na porção basal e outro na porção superior. Em ambos, a deposição final das conchas ocorreu sob a influência de eventos episódicos de alta energia. As espécies encontradas no intervalo basal compreendem Cowperesia emerita, Terraia cf. altissima e Terraia cf. curvata, enquanto no intervalo superior apenas Huabiella compressa gênero e espécie novos, e Terraia cf. curvata estão presentes Os táxons sugerem correlação entre a Formação Gai-As e a porção basal do Membro Serrinha, Formação Rio do Rasto. Adicionalmente, conforme dados prévios de literatura, na Formação Gai-As, logo acima das últimas ocorrências de bivalves do intervalo superior, existem tufos vulcânicos, cuja datação radiométrica de minerais de zircão indica idades em torno de 265+2.5 Ma., aproximadamente no limite Wordiano-Capitaniano. Essas idades são muito próximas das recentemente obtidas para minerais de zircão de cinzas vulcânicas na Formação Teresina (267±17 Ma.) e no Membro Serrinha 266.3±4.6 Ma. da Bacia do Paraná / The taxonomic study of bivalve mollusks of the Gai-As Formation, Permian, Huab area, Namibia, allowed the identification of species previously recorded only in the Permian Passa Dois Group, Paraná Basin, Brazil, improving the stratigraphical correlations between both basins. In the Gai-As Formation, bivalve shells are recorded in two well defined stratigraphical intervals, in the lower and upper portions. In both cases, the final deposition of the bivalve shells was a result of high energy episodic events. The species recorded in the lower portion are Cowperesia emerita, Terraia cf. altissima and Terraia cf. curvata. In the upper portion there are Huabiella compressa new gen. and sp., and Terraia cf. curvata. These bivalve species corroborate the correlation of Gai-As Formation to the lower portion of the Serrinha Member, Rio do Rasto Formation. Additionally, according to literature, in Gai-As Formation, fallout tuffs deposited immediately above the last occurrences of bivalves of the upper portion, bear zircon grains, whose radiometric shrimp U/Pb dating provided ages of 265±2.5 Ma., equivalent to the Wordian-Capitanian boundary. This age is very close to that recently recorded from zircon grains found in ash-beds of the Teresina Formation (267±17 Ma.) and the Serrinha Member (266.3±4.6 Ma.) of the Paraná Basin
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Contribuição ao conhecimento de Macoma (Austromacoma) constricta (Bruguière, 1792) (Bivalvia, Heterodonta, Tellinidae)Geraldes, Inês Lepore Ferreira 29 December 1982 (has links)
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Previous issue date: 1982-12-29 / Estudo sobre bivalves marinhos da subfamília Macominae Olsson, 1961, são apresentadas as caracterizações dos grandes grupos desde subclasse até subfamília, a fim de situar a referida subfamília entre os Bivalvia. Dos gêneros e subgêneros são apresentadas as caracterizações, distribuições geológica a geográfica, considerações e ilustrações gerais das conchas de espécies representadas no litoral brasileiro. Sobre Macoma (Austromacoma) constricta (Bruguière, 1792), espécie Recente, que ocorre da Carolina do Norte (EUA) até o Rio Grande do Sul (Brasil), foram realizados estudos detalhados, com base no material examinado e bibliografia consultada, compreendendo: dados taxonômicos, aspectos anatômicos e microanatômicos, observações sobre as correntes ciliares no manto, sobre o local de captura (Praia do Cardo, Baía de Sepetiba, RJ) e sobre o animal em aquário. / Studies on marine bivalves of the Subfamily Macominae Olsson, 1961, the characterization of the major groups, from subclass to subfamily, is presented in order to place the refered subfamily among the Bivalvia. Characterization, as well as geological and geographic distribution, is presented for the genera and subgenera, along with general considerations and illustrations of the shells of the species occuring on the Brazilian coast. ln relation to Macoma (Austromacoma) constricta (Bruguière, 1792), a recente species which occurs from North Carolina (USA) to Rio Grande do Sul (Brazil), detailed studies were developed based both in the material examined and in the bibliography. These studies comprised: taxonomy, anatomical and microanatomical remarks, comments on ciliary currents in the mantle, data related to the collecting site (Praia do Carbo, Baía de Sepetiba, RJ), and observations of the animal in aquarium.
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Contribuição ao conhecimento de Dosinia (D.) concentrica (Born, 1778) (Bivalvia, Heterodonta, veneridae)Guéron, Cordélia de Oliveira Castro January 1979 (has links)
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Previous issue date: 1979 / Estudo sobre moluscos bivalves, marinhos, caracterizando os grandes grupos até subfamílias ocorrentes no Brasil, indicando respectivamente as espécies representativas dos subgêneros e gêneros correspondentes, ilustrando uma das espécies de cada subgênero. São assinaladas no Brasil, para a família Veneridae, oito subfamílias, quinze gêneros, vinte subgêneros e trinta e seis espécies, sendo a espécie Dosinia (D.) concentrica (Born, 1778) a única representante do gênero Dosinia Scopoli, 1777 no litoral brasileiro, de distribuição conhecida, do Pará a Santa Catarina. Com Dosinia (D.) concentrica (Born, 1778) foram realizados estudos detalhados, baseados no material examinado e na bibliografia levantada, focalizando os aspectos taxonômicos, geológicos, biogeográficos e morfológicos de suas partes duras e moles.
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A Behavioral Model for Detection of Acute Stress in BivalvesAllen, H. Joel 05 1900 (has links)
A behavioral model for acute responses in bivalves, was developed using time series analysis for use in a real-time biomonitoring unit. Stressed bivalves closed their shell and waited for the stressful conditions to pass. Baseline data showed that group behavior of fifteen bivalves was periodic, however, individuals behaved independently. Group behavior did not change over a period of 20 minutes more than 30 percent, however, following toxic exposures the group behavior changed by more than 30 percent within 20 minutes. Behavior was mathematically modeled using autoregression to compare current and past behavior. A logical alarm applied to the behavior model determined when organisms were stressed. The ability to disseminate data collected in real time via the Internet was demonstrated.
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Seasonal gonadal changes in two bivalve mollusks in Tomales Bay, CaliforniaLeonard, Vernon Kenneth 01 January 1968 (has links)
Pododesmus cepio Gray (1850), a bivalve mollusk of Family Anomiidae, is native to the Pacific coast of North America and common in Tomales Bay, California. A small population of the European oyster, Ostrea edulis Linnaeus (1758), is being raised experimentally at the Tomales Bay Oyster Company. The histological study of the seasonal gonadal changes of these two species, in Tomales Bay, is described below.
The study of gametogenesis in O. edulis in Tomales Bay is desired to evaluate the reproductive adaptation of this animal to a new set of ecological conditions. The inclusion of the native P. cepio in this study allows comparison of the gonadal development of these two species. Such a comparison aids not only in understanding the seasonal gonadal changes in both species, but also in examining the adjustment of the introduced form, O. edulis, to a new environment.
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The effect of chronic copper exposure on the energy budget of two mussels, perna viridis (L.) and septifer virgatus (Wiegmann)Sze, Wai-chung., 施慧中. January 1995 (has links)
published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy
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Sambandet mellan fetch och förekomst av stormusslor : En studie i Vänern / Relation between fetch and frequency of swedish freshwater mussels : A study in lake VänernLawenius, Tove January 2018 (has links)
Sötvattensmusslor är viktiga i ekosystem där de finns, för människan utgör de även en ekosystemtjänst då de filtrerar vatten. De stora sötvattensmusslorna kallas stormusslor och finns i både sjöar och vattendrag i Sverige. I Vänern har fyra av de inhemska arterna noterats. Fetchen är längden på den öppna vattenytan från en punkt på land till närmsta land eller ö. Beroende på en strands storlek på fetch kan bottensedimentet se annorlunda ut. Musslorna är bottenlevande och spenderar mycket tid nedgrävda i bottensedimenten. När musslorna är uppe och filtrerar på bottenytan sitter de halvt nergrävda med bakänden uppåt. I denna rapport presenteras stormusslornas förekomst och dess relation till stränders fetch. Mer kunskap om stormusslorna behövs för att kunna utveckla ett mer anpassat naturvårdsarbete för dem. Inventering av musslor har skett på 20 olika platser i sydöstra Vänernområdet. Denna studie visar att en trend till ett samband finns mellan förekomst av stormusslor och lokalens fetch. Fetchen påverkar den maximala tätheten som musslorna kan uppnå. Analys ger statistisk signifikans på att tätheten minskar med ökad fetch. Tidigare forskning visar på liknande resultat. Emellertid tycks fler variabler vara beroende faktorer för hur mycket och om fetchen påverkar musslorna. / Freshwater bivalves are important organisms in the ecosystems they live, they also function as an ecosystem service for the human society. Swedish freshwater bivalves are divided into two groups; one with freshwater clams Sphaeriidae, and freshwater mussel with polyphile bivalves that are larger. Freshwater mussel lives in lakes and rivers, in Lake Vänern four species of the Swedish freshwater mussel have been observed. Fetch is the length of the open water from a point on shore to the nearest land or island. The structure of the lake bottom sediment can vary dependent on what value of fetch a shore has. In this report the freshwater mussel’s relation to the shore fetch is presented. More knowledge of the freshwater mussel is needed to develop a more suitable conservation work for them. Inventory of mussel have been done on 20 different places in the southeast area of Lake Vänern. The results in this study shows a trend towards a relation between presence of freshwater mussel and shore fetch. Analysis on the highest density of mussel when the fetch data is divided in different classes shows a statistic significance for reduced density of mussel with increased fetch. Previous research shows similar results. However, more variables seem to be dependent factors for how and if fetch affect mussel.
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