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Análise da estruturação genética da sub-espécie Patella candei gomesii Drouet 1858 (Mollusca: Gastropoda: Patellidae) no arquipélago dos Açores

Tavares, Ana Sofia Sona
Fonte: Porto : [s.n.] Publicador: Porto : [s.n.]
Tipo: Dissertação
POR
Relevância na Pesquisa
26.57%

Distribuição de Patella candei gomesii d’Orbigny 1839 em diferentes tipologias de habitats naturais em S. Miguel, Açores

Tracana, Andreia Filipa Gonçalves, 1988-
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2013 POR
Relevância na Pesquisa
67.86%
Tese de mestrado. Biologia (Ciências do Mar). Universidade de Lisboa, Faculdade de Ciências, 2013; O intertidal é das áreas mais exploradas dos oceanos devido à sua fácil acessibilidade, diversidade ambiental, riqueza de organismos e facilidade de os observar. As condições ambientais variam de tal forma que os organismos intertidais possuem adaptações específicas para poderem viver nesse ambiente. Nos Açores, o intertidal é constituído por escarpas altas e ingremes, com praias de escoada, blocos e areia. De origem basáltica, é substrato para musgos algais, algas frondosas e crostosas e invertebrados como cracas, litorinas e lapas. P. candei gomesii é uma subespécie que só existe nos Açores e encontra-se no intertidal e no subtidal pouco profundo. Esta lapa é sujeita a uma exploração elevada podendo levar a extinção e consequentemente à dominância algal no intertidal açoriano. O objectivo do presente estudo é avaliar se existem diferenças na distribuição e no tamanho da lapa Patella candei em diferentes habitats naturais da zona intertidal (blocos e escoada lávica) da ilha de São Miguel. Procedeu-se à realização de quantificações e de medições dos organismos associados aos substratos, assim como à recolha de fotografias...

Bioavailable metals and cellular effects in the digestive gland of marine limpets living close to shallow water hydrothermal vents.

Cunha, Luís; Amaral, André; Medeiros, Vera; Martins, Gustavo M.; Wallenstein, Francisco; Couto, Ruben P.; Neto, Ana I.; Rodrigues, Armindo
Fonte: ELSEVIER Publicador: ELSEVIER
Tipo: Artigo de Revista Científica
Publicado em /04/2008 ENG
Relevância na Pesquisa
47.16%
Copyright © 2007 Elsevier Ltd All rights reserved.; The pressure exerted by shallow water hydrothermal vents on edible gastropods and their cellular responses triggered by these stresses are almost unknown. The aims of this study were to evaluate the bioavailability of metals in the Macaronesian endemic limpet Patella candei gomesii living close to shallow water hydrothermal vents, and the structural differences in their digestive gland as well as the levels of apoptosis in that organ. Limpets were sampled in four sites, two with the presence of hydrothermalism and the other two without it. Whole body concentrations of several metals (Ca, Cd, Cs, Co, Cu, Fe, Hg, Mg, Mn, Pb, Rb, Se, Sr, and Zn) were obtained, morphometry analysis of the digestive gland and TUNEL test for apoptosis were also performed. Results revealed that the presence of shallow water hydrothermal vents is a source of chronic metal stress to limpets, imposing modifications in the morphometry and cell composition of the digestive gland of those limpets that may constitute cell and tissue adaptations to the environment they live in. This study sets up new baseline data for further research on the influence of shallow water hydrothermal vents over communities living in these habitats.

The reproductive cycle of Patella candei gomesii Drouët, 1858 (Mollusca: Patellogastropoda), an Azorean endemic subspecies

Curdia, João; Rodrigues, Armindo; Martins, António M. de Frias; Costa, Manuel
Fonte: Balaban, Philadelphia/Rehovot Publicador: Balaban, Philadelphia/Rehovot
Tipo: Artigo de Revista Científica
Publicado em //2005 ENG
Relevância na Pesquisa
67.58%
Copyright © 2005, Taylor & Francis.; Patella candei gomesii is morphologically plastic comprising two ecomorphs. The “smooth limpet” is characteristic of the eulittoral zone, whereas the “fly limpet” is mainly found higher in the shore, on the splash zone of exposed areas. Their reproductive strategies are poorly understood. This study investigated the reproductive cycles of the ecomorphs using histological techniques. The annual cycles were found to be similar. Both sexes exhibited synchronous patterns and were mature most of the year. In April, significant increases were observed in the relative volume occupied by previtellogenic and vitellogenic cells in females, and by spermatogonia, spermatids and spermatocytes in males. The maximum values for mature oocytes and spermatozoa were observed in July. It is concluded that the breeding season of P. candei gomesii lasts the whole year peaking in the summer (when reproductive condition is highest and the main spawning event must occur). The implications of these findings for the taxonomy and conservation of the subspecies are further discussed.

A case of simultaneous hermaphroditism in the Azorean endemic limpet Patella candei gomesii (Mollusca: Patellogastropoda), a gonochoristic species

Cunha, Luís; Martins, Gustavo M.; Amaral, André; Rodrigues, Armindo
Fonte: Balaban, Philadelphia/Rehovot Publicador: Balaban, Philadelphia/Rehovot
Tipo: Artigo de Revista Científica
Publicado em /11/2007 ENG
Relevância na Pesquisa
47.16%
Copyright © 2007, Taylor & Francis.; A case of simultaneous hermaphroditism was observed in Patella candei gomesii, an Azorean endemic species, which has been considered a gonochoristic species. Here we show that simultaneous hermaphroditism can occur within the family Patellidae.

Limpet shell modifications at intertidal hydrothermal vents.

Couto, Ruben P.; Neto, Ana I.; Rodrigues, Armindo
Fonte: Universidade dos Açores Publicador: Universidade dos Açores
Tipo: Conferência ou Objeto de Conferência
Publicado em /08/2010 ENG
Relevância na Pesquisa
26.57%
45th European Marine Biology Symposium. Edinburgh, Escócia, 23-27 de Agosto de 2010.

Microhabitat provision influences small-scale patterns of distribution in Patella candei.

Martins, Gustavo M.; Thompson, Richard C.; Neto, Ana I.; Hawkins, Stephen J.; Jenkins, Stuart R.
Fonte: Universidade dos Açores Publicador: Universidade dos Açores
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2008 ENG
Relevância na Pesquisa
47.16%
43rd European Marine Biology Symposium. Ponta Delgada, Açores, 8-12 de Setembro de 2008.

Limpet shell modifications at intertidal hydrothermal vents

Couto, Ruben P.; Neto, Ana I.; Rodrigues, Armindo
Fonte: APRH - Associação Portuguesa dos Recursos Hídricos Publicador: APRH - Associação Portuguesa dos Recursos Hídricos
Tipo: Artigo de Revista Científica
Publicado em /06/2012 ENG
Relevância na Pesquisa
47.47%
Copyright © 2012 APRH.; Os organismos calcários são conhecidos por serem sensíveis à água do mar acidificada, e têm sido apontados como potenciais sentinelas para estudos sobre acidificação do oceano. As lapas estão entre os organismos que caracterizam a zona intertidal e nos Açores, podendo também ser encontradas em locais com actividade hidrotermal de superfície, onde a acidez da água do mar na proximidade das fontes hidrotermais é naturalmente mais elevada devido à liberação de CO2. Durante uma visita ocasional para avaliar a ocorrência e abundância de algas no intertidal encontraram-se vários espécimes de Patella candei gomesii (Patellidae) com conchas aberrantes, na proximidade de fontes hidrotermais. Estes indivíduos, colectados sob tais condições exibiam conchas frágeis, quase transparentes, com espessura muito reduzida.; ABSTRACT: Calcareous organisms are known to be sensitive to acidified seawater, and they have been reported as potential sentinels for ocean acidification studies. Limpets are among the organisms that characterise intertidal zones, and in the Azores can also be found at sites with shallow water hydrothermal activity, where the acidity of seawater in the vicinity of hydrothermal vents is naturally higher due to CO2 release. During an occasional intertidal survey on the occurrence and abundance of intertidal algae we found limpets with abnormal shells...

Exploitation of rocky intertidal grazers: population status and potential impacts on community structure and functioning.

Martins, Gustavo M.; Jenkins, Stuart R.; Hawkins, Stephen J.; Neto, Ana I.; Thompson, Richard C.
Fonte: Inter Research Publicador: Inter Research
Tipo: Artigo de Revista Científica
Publicado em /07/2008 ENG
Relevância na Pesquisa
26.81%
Copyright © Inter-Research 2008.; A wide range of anthropogenic activities are impacting the ecology of coastal areas. Exploitation of marine resources is one such activity, which, through cascading trophic effects, can have influences well beyond that of the target species. We investigated the mid-rocky-shore community structure of the Azores archipelago, a seldom-studied habitat, where there is a local tradition of exploiting limpets, the main intertidal grazers. The limpet population structure differed among islands, and there was an inverse relationship between the abundance of larger limpets and the human population per coastal perimeter, but not the associated catch data. At small scales of resolution (quadrats), there was a negative relationship between the cover of algae and limpets and a positive relationship between barnacles and limpets. These relationships were also apparent at the larger scale of islands as a function of the gradient of exploitation. Our results show how natural habitat fragmentation may be useful where the experimental testing of a hypothesis is not possible, and provide evidence for the trophic cascading effects of limpet exploitation at landscape scales.

Illegal harvesting affects the success of fishing closure areas.

Martins, Gustavo M.; Jenkins, Stuart R.; Hawkins, Stephen J.; Neto, Ana I.; Medeiros, André; Thompson, Richard C.
Fonte: Marine Biological Association of the United Kingdom Publicador: Marine Biological Association of the United Kingdom
Tipo: Artigo de Revista Científica
Publicado em /06/2011 ENG
Relevância na Pesquisa
36.81%
Copyright © Marine Biological Association of the United Kingdom 2010.; There is clear evidence that marine reserves can be used as effective tools to foster the recovery of disturbed ecosystems. In the Azores, intense exploitation of the patellid limpets Patella candei and P. aspera has led to a rapid decline in their populations and subsequent collapse of the fishery in 1985. In 1993, legislation was passed to protect limpets, including the establishment of limpet protected zones (LPZs) where harvesting was completely prohibited. Outside LPZs, a seasonal fishing closure prohibited the harvesting of limpets from October to May. Here we examine the effect of such measures 16 years after they were put into practice. In each of the 3 years examined, limpet density, biomass and size were generally similar both inside and outside the LPZs. In addition, there were clear signs of exploitation as most individual limpets inside the LPZ were smaller than the legal catch size suggesting that illegal harvesting was taking place. Observations confirmed that illegal harvesting of limpets was common both inside and outside LPZs. Lack of enforcement of regulations is therefore a likely reason for the failure of legislation to protect limpet populations and facilitate stock recovery.

Shell variation in Patellid limpets: scales of spatial variability

Martins, Gustavo M.; Faria, João; Furtado, Miguel; Enes, Manuel; Neto, Ana I.
Fonte: Sociedade Afonso Chaves Publicador: Sociedade Afonso Chaves
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 ENG
Relevância na Pesquisa
47.66%
World Congress of Malacology, Universidade dos Açores, Ponta Delgada, 21-28 de julho.; Species o f the genera Patella generally display a high degree of shell variation, which is thought to be an adaptation to environmental conditions. The present work examines the variation in the morphometry of the two patellid limpets present in the Azores (Patella candei and P. aspera) at multiple spatial scales. Individuals of both patellid species were collected on two sites in each of the nine islands of the Azores. All individuals were measured to estimate base ellipticity, base eccentricity, conicity and cone eccentricity. Shell variation in P. candei was consistent among groups of islands (eastern, central, western) but there was significant variation in shell morphometry at the scales of islands and sites. Components of variation showed that a substantial proportion of variation was associated with the scale of individuais. Shell variation in P. aspera was consistent at the scale of island groups and islands but there was significant variation among sites. Analysis of the components of variability showed that variability in shell morphometrv was mostly associated with differences among individuais. Overall, these results suggest that variation in shell morphometry in the two patellid is not influenced by large scale processes as would be expected given that P. candei and P. aspera both have a pelagic Iarvae. In addition...

Conservation of limpet populations: a heavily exploited resource in Azores, NE-Atlantic

Faria, João; Ribeiro, Pedro; Martins, Gustavo M.; Rivas, Manuel; Hawkins, Stephen J.; Presa, Pablo; Neto, Ana I.
Fonte: Universidade dos Açores Publicador: Universidade dos Açores
Tipo: Conferência ou Objeto de Conferência
Publicado em //2014 ENG
Relevância na Pesquisa
26.81%
10th International Temperate Reefs Symposium, The University of Western Australia, 12-17 de janeiro.; Limpet harvesting in Azores (NE Atlantic) has been taking place probably since the islands were first colonized in the XV century. Limpet species are highly exploited and populations from most islands have declined steadily bringing about catastrophic effects on coastal communities. Despite their economic importance limpets are also ecologically key species and require prioritizing conservation strategies. Patellid limpets are broadcast spawners which go through a planktonic larval stage in their life cycle. They are benthic as adults and the larva is the only phase during their life-cycle which has the ability to disperse over assumed large spatial distances. However, there is now mounting evidence that gene flow between islands and mainlands can be low, even for species with a relatively long planktonic larval stage. Low levels of larval exchange may thus limit the success of conservation objectives expected upon migration and recruitment. In dispersive isolated oceanic islands such as the Macaronesian Islands, the Azores Archipelago in particular, is not clear whether limpet populations from different islands form a single meta-population or...

Genetic population structure and connectivity of Azorean limpets

Faria, João; Presa, Pablo; Martins, Gustavo M.; Ribeiro, Pedro; Neto, Ana I.
Fonte: Universidade dos Açores Publicador: Universidade dos Açores
Tipo: Conferência ou Objeto de Conferência
Publicado em //2014 ENG
Relevância na Pesquisa
16.57%
Ocean Science Meeting. Hawaii Convention Center, Honolulu, Hawaii, USA, 23-28 de Fevereiro.; There is growing consensus that anthropogenic activities significantly rarefy the structure and functioning of marine ecosystems. Oceanic islands such as the Azores (NE Atlantic) constitute unique habitats with fragile communities, which are highly susceptible to degradation and ecosystem disruption. . Patellid limpets have traditionally been collected as a food resource and in 1988 the limpet fishery in São Miguel Island collapsed, and after a one-year ban throughout the archipelago, the stocks were allowed to recover, avoiding catastrophic overexploitation effects. In 1993, legislation was passed to protect this resource, i.e. limpet no-take areas were created, seasonal harvesting restrictions were applied and minimum legal catch sizes were established. However, a recent survey has shown that limpet populations still show clear signs of overexploitation and some populations are virtually extinct in some islands. Here we have developed new multiplexed and described microsatellite markers for the species Patella aspera and P. candei and have examined their genetic diversity, gene flow and population connectivity in the Azores Archipelago. Overall...

Enhancing stocks of the exploited limpet Patella candei d'Orbigny via modifications in coastal engineering

Martins, Gustavo M.; Thompson, Richard C.; Neto, Ana I.; Hawkins, Stephen J.; Jenkins, Stuart R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /01/2010 ENG
Relevância na Pesquisa
47.34%
Copyright © 2009 Elsevier Ltd. All rights reserved.; It is widely recognised that microhabitats are important for a variety of marine organisms, yet this knowledge has rarely been applied in the construction of engineered structures as a means of enhancing biodiversity or populations of species at risk. Here we examined the influence of microhabitats on the distribution and survival of the exploited limpet Patella candei on natural shores before determining the effect of introducing such habitats to an artificial seawall. On natural shores individuals were associated with pits (a natural feature of volcanic rocky shores). Animals inhabiting pits showed reduced mortality and were smaller than those on open rock. Microhabitat utilisation was similar over the vertical range of distribution of P. candei. Following observation of natural patterns, we applied this knowledge by experimentally drilling pits at varying densities and sizes in a seawall that had been constructed with simple topographical complexity. Overall, the number of animals increased in areas with experimentally increased microhabitat area. There was evidence that this was the result of immigration (larger animals) but also of increased recruitment. This study demonstrates one cost-effective way of conciliating the need to protect our coastlines while promoting the conservation and stock enhancement of over-exploited species.

Development and characterization of microsattelite Loci for the harvested limpets Patella Candei (D'orbigny, 1839) and Patella Aspera (Röding, 1798) using 454 sequencing

Rivas, Manuel; Faria, João; Ribeiro, Pedro; Presa, Pablo; Martins, Gustavo M.; Neto, Ana I.
Fonte: Sociedade Afonso Chaves Publicador: Sociedade Afonso Chaves
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 ENG
Relevância na Pesquisa
67.75%
World Congress of Malacology, Ponta Delgada, July 22-28, 2013.; There is growing consensus that anthropogenic activities are impacting the structure and functioning of marine ecosystems and that these can have profound community level effects, particularly when targeting keystone species. Limpet harvesting in Azores (NE Atlantic) has been taking place probably since the islands were first colonized. These species are highly exploited and the stocks in most islands have declined steadily with catastrophic effects on coastal communities. They are a locally important resource but also ecologically important species and require prioritizing conservation strategies. Such strategies should be su pported by reliable data on the structure and dynamics of their populations, so that ecological hotspots are identified and protected. Characterizing the genetic diversity and structure of marine exploited populations is thus of paramount importance to identify such units of conservation. Here we describe and develop species-specific microsatellite markers for the harvested limpets Patella candei and Patella aspera using whole genome shotgun 454 sequencing. A total of 309 bioinformatic-validated pairs of primers were obtained from P. aspera microsatellite enriched library. The optimization of the amplification conditions of selectect microsatellites (simplex and multiplex reactions) was performed in a gradient thermal cycler to optimize locus-specific amplification conditions and test their utility as genetic markers. Forty pairs of primers were tested...