55 research outputs found
Molecular evidence for extensive discontinuity between peracarid (Crustacea) fauna of Macaronesian islands and nearby continental coasts: over fifty candidate endemic species
Oceanic islands are recognized evolutionary hotspots for terrestrial organisms, but little is known about their impact on marine organisms' evolution and biogeography. The volcanic archipelagos of Macaronesia occupy a vast and complex region in the Atlantic Ocean and may be particularly suitable to investigate marine island biogeography. In this study, we used mitochondrial DNA sequences (cytochrome c oxidase subunit I DNA barcoding region) to investigate the genetic differentiation between the populations from Webbnesia (i.e. Madeira, Selvagens and Canary Islands) and adjacent coasts (Azores, Continental Iberian Peninsula and Morocco) of 23 intertidal peracarid species. All species had high intraspecific genetic distances (>3%), reaching more than 20% in some cases. Between 79 and 95 Molecular Operational Taxonomic Units (MOTUs) were found in these species. Webbnesia populations displayed high genetic diversity and high endemicity, with 83% of the MOTUs being private to these islands, particularly La Palma and Madeira. Artificial community network analyses based on MOTU occurrence suggested higher similarity between Webbnesia and Azores than with adjacent continental coasts. These results reveal an unanticipated and strong biogeographic discontinuity of peracaridean fauna between Webbnesia and the Iberian Peninsula, a pattern that may occur in other groups of marine invertebrates in the region. We emphasize the unique genetic heritage hosted by these islands, underlining the need to consider the fine scale endemicity in marine conservation efforts.The authors wish to thank the colleagues who helped during fieldwork, sample processing and/or laboratory work: Tavares M and Santos R (University of Algarve, Portugal), Ladeiro B, Peteiro L, Gomes I, Albuquerque R, GuimarAes B and Fuente N (University of Aveiro, Portugal) and Gomes N (University of Minho, Portugal). Additionally, thanks to Carvalho D in the name of the Portuguese Museum of Natural History and Science of Lisbon for supplying material from the EMEPC/M@rBis/Selvagens2010 and EMAM/PEPC_M@rBis/2011 campaigns to Selvagens. Thanks to Bellisario B for feedback regarding network analysis. Finally, thanks to Ferreira EL for the use of some equipments. This work was supported by the project "DiverseShores-Testing associations between genetic and community diversity in European rocky shore environments (PTDC/BIA-BIC/114526/2009)" funded by the Fundacao para a Ciencia e Tecnologia (FCT) under the COMPETE programme supported by the European Regional Development Fund. FCT also supported a PhD grant to PEV (SFRH/BD/86536/2012). Thanks to FCT/MCTES are also due for the financial support to CESAM (UIDP/50017/2020+UIDB/50017/2020), through national funds. PE was funded through FCT in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23 of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19
Site fidelity of Hippocampus guttulatus Cuvier, 1829 at Mar Piccolo of Taranto (Southern Italy; Ionian Sea)
AbstractLack of detailed knowledge on ecological niche, life cycles, spatial distribution, reproductive biology and space use strongly affects the selection of useful tools and measures in the conservation of threatened marine species. Especially for sedentary and slow species, behaviour and movement capacities are supposed to be the most important functional traits. Indeed, behavioural variability concerning available space and the close presence of individuals is considered a crucial trait for the population dynamics assessments, especially when disturbances of various causes are present in the environment. The present study aimed to investigate the site fidelity and degree of movement of Hippocampus guttulatus, an emblematic and threatened Mediterranean seahorse species. With this aim, a number of seahorses were tagged and monitored throughout two years within a limited area of the lagoon of Mar Piccolo of Taranto (Southern Italy). The studied individuals were initially morphometrically measured for size, sex and life-cycle stage and subsequently monitored through repeated four-month surveys each year. Obtained results indicated high site fidelity regardless of habitat type. Movement pattern was in line with the data on congeneric species, although values were slightly higher. The analyses showed differences in movement degree among different sexes and life-cycle stages and indicated greater mobility of adult females compared to males and juveniles. The investigated parameters showed a great variability suggesting that even small-scale environmental factors can influence the species mobility. Finally, a change in the population structure has been observed, with the loss of large individuals in 2016 and reduced recruitment in 2017. These findings indicated the possible presence of stressors that could lead to the alteration of the seahorse population at Mar Piccolo of Taranto
Neonicotinoid Clothianidin reduces honey bee immune response and contributes to Varroa mite proliferation
The neonicotinoid Clothianidin has a negative impact on NF-\u3baB signaling and on immune responses controlled by this transcription factor, which can boost the proliferation of honey bee parasites and pathogens. This effect has been well documented for the replication of deformed wing virus (DWV) induced by Clothianidin in honey bees bearing an asymptomatic infection. Here, we conduct infestation experiments of treated bees to show that the immune-suppression exerted by Clothianidin is associated with an enhanced fertility of the parasitic mite Varroa destructor, as a possible consequence of a higher feeding efficiency. A conceptual model is proposed to describe the synergistic interactions among different stress agents acting on honey bees
Neonicotinoid Clothianidin reduces honey bee immune response and contributes to Varroa mite proliferation
The neonicotinoid Clothianidin has a negative impact on NF-κB signaling and on immune responses controlled by this transcription factor, which can boost the proliferation of honey bee parasites and pathogens. This effect has been well documented for the replication of deformed wing virus (DWV) induced by Clothianidin in honey bees bearing an asymptomatic infection. Here, we conduct infestation experiments of treated bees to show that the immune-suppression exerted by Clothianidin is associated with an enhanced fertility of the parasitic mite Varroa destructor, as a possible consequence of a higher feeding efficiency. A conceptual model is proposed to describe the synergistic interactions among different stress agents acting on honey bees
The Environmental Effects of the Innovative Ejectors Plant Technology for the Eco-Friendly Sediment Management in Harbors
A sediment bypassing plant based on innovative jet pump, ejectors, has been tested in the
first-of-a-kind demo application at the harbor of Cervia (Italy, Northern Adriatic Sea). The ejector is
a jet pump aimed to reduce sediment accumulation in navigation channels and coastal areas.
Herein we present results of the first study assessing the potential ecological effects of the ejectors
plant. Sediment characteristics, benthic, and fish assemblages before and after the plant activation
have been analyzed in the putatively impacted (the sediment removal and discharge) areas and
four control locations, one time before and two times after plant activation. Ejectors plant operation
resulted in a reduction of the mud and organic matter content in the sediment, as well as in
changes in shell debris amount in the impacted areas. Abundance and species richness of benthic
macroinvertebrates, initially reduced in the impacted areas, probably due to the previous repeated
dredging, returned to higher values during demo plant continuous operation. Higher diversity of
fish fauna was observed in the study area during plant operation period. Observed dynamics of the
ecological status of the marine habitat suggest that an ejectors plant could represent an eco-friendly
solution alternative to dredging operations to solve harbor siltation problems
Ancient globetrotters—connectivity and putative native ranges of two cosmopolitan biofouling amphipods
The geographic distributions of some coastal marine species have appeared as cosmopolitan ever since they were first scientifically documented. In particular, for many benthic species that are associated with anthropogenic substrata, there is much speculation as to whether or not their broad distributions can be explained by natural mechanisms of dispersal. Here, we focused on two congeneric coastal crustaceans with cosmopolitan distributions—the tube-dwelling amphipods Jassa marmorata and Jassa slatteryi. Both species are common elements of marine biofouling on nearly all kinds of artificial hard substrata in temperate to warm seas. We hypothesized that the two species’ modern occurrences across the oceans are the result of human shipping activities that started centuries ago. Mitochondrial DNA sequences of the CO1 fragment of specimens from distinct marine regions around the world were analysed, evaluating genetic structure and migration models and making inferences on putative native ranges of the two Jassa species. Populations of both species exhibited considerable genetic diversity with differing levels of geographic structure. For both species, at least two dominant haplotypes were shared among several geographic populations. Rapid demographic expansion and high migration rates between geographically distant regions support a scenario of ongoing dispersal all over the world. Our findings indicate that the likely former native range of J. marmorata is the Northwest Atlantic, whereas the likely former native range of J. slatteryi is the Northern Pacific region. As corroborated by the genetic connectivity between populations, shipping still appears to be the more successful vector of the two species’ dispersal when compared to natural mechanisms. Historical invasion events that likely started centuries ago, along with current ongoing dispersal, confirm these species’ identities as true “neocosmopolitans”
Finding aquaporins in annelids : An evolutionary analysis and a case study
Funding Information: This research was funded by PRIN2017 Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale 2017 (grant # 2017J92TM5) by Italian MUR to G.C. and by the Molecular Bio-diversity Laboratory of the Italian node of Lifewatch (CNR, Consiglio Nazionale delle Ricerche) to C.G.Peer reviewedPublisher PD
Benthic microbial biogeographic trends in the North Sea are shaped by an interplay of environmental drivers and bottom trawling effort
Microbial composition and diversity in marine sediments are shaped by environmental, biological, and anthropogenic processes operating at different scales. However, our understanding of benthic microbial biogeography remains limited. Here, we used 16S rDNA amplicon sequencing to characterize benthic microbiota in the North Sea from the top centimeter of 339 sediment samples. We utilized spatially explicit statistical models, to disentangle the effects of the different predictors, including bottom trawling intensity, a prevalent industrial fishing practice which heavily impacts benthic ecosystems. Fitted models demonstrate how the geographic interplay of different environmental and anthropogenic drivers shapes the diversity, structure and potential metabolism of benthic microbial communities. Sediment properties were the primary determinants, with diversity increasing with sediment permeability but also with mud content, highlighting different underlying processes. Additionally, diversity and structure varied with total organic matter content, temperature, bottom shear stress and bottom trawling. Changes in diversity associated with bottom trawling intensity were accompanied by shifts in predicted energy metabolism. Specifically, with increasing trawling intensity, we observed a transition toward more aerobic heterotrophic and less denitrifying predicted metabolism. Our findings provide first insights into benthic microbial biogeographic patterns on a large spatial scale and illustrate how anthropogenic activity such as bottom trawling may influence the distribution and abundances of microbes and potential metabolism at macroecological scales
Phylogeny and phylogeography of the family Hyalidae (Crustacea: Amphipoda) along the northeast Atlantic coasts
The family Hyalidae comprises more than one hundred species, distributed worldwide. They are common and abundant in the littoral and shallow sublittoral habitats and they play an important role in the coastal food chain. Most studies about this family were dealing with taxonomy and ecology, while very little is known about phylogenetic relationship among genera and species.
In the present study we aim to achieve the first approach of the phylogenetic patterns of this family in NE Atlantic Ocean and Mediterranean Sea, and to perform the first insight into the phylogeography Apohyale prevostii along both the North Atlantic coasts. In order to do that, eight species belonging to the genera Apohyale, Hyale, Serejohyale and Protohyale were investigated using the mitochondrial COI-5P barcode region. Specimens were collected along European and Moroccan Atlantic rocky shores, including Iceland, the British Isles, Macaronesia and in the Mediterranean Sea. Sequences of A. prevostii, from the NW Atlantic Ocean, available in BOLD and GenBank, were retrieved.
As expected, phylogenetic analyses showed highly-divergent clades, clearly discriminating among different species clusters, confirming their morphology-based identifications. Although, within A. perieri, A. media, A. stebbingi, P. (Protohyale) schmidtii and S. spinidactylus, high genetic diversity was found, revealing putative cryptic species. The clade of A. prevostii and A. stebbingi appears well supported and divided from the other two congeneric species, and P. (Protohyale) schmidtii shows a basal divergence.
The north-western Atlantic coasts were recently colonized by A. prevostii after the last glacial maximum from the European populations showing also a common haplotype in every population analysed.
The use of the COI-5P as DNA barcode provided a good tool to underline the necessity of a revision of this emblematic family, as well as to discern taxonomically the possible new species flagged with this molecular device
Amphipod fouling : diversity, biogeography and drivers of an understudies community
Orientadora: Prof. Maria Angélica HaddadCoorientador: Dr. Jan BeermannTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Zoologia. Defesa : Curitiba, 07/12/2020Inclui referênciasResumo: Substratos artificiais imersos em ambientes marinhos e estuarinos são, em geral, rapidamente colonizados por uma comunidade incrustante (fouling) que é conhecida por diminuir a flutuabilidade das bóias, obstruir dutos e afetar a hidrodinâmica dos barcos. No entanto, a fauna vágil do fouling ainda é comparativamente pouco estudada. As comunidades do fouling foram reconhecidas como stepping-stones para as espécies introduzidas não nativas (NIS), que, ao chegarem nos portos, também podem se espalhar para habitats naturais próximos. A principal hipótese desta tese - de que a proximidade de portos afeta negativamente as comunidades do fouling em sua composição (mais NIS perto dos portos), estrutura (proteção de barreiras ambientais entre estuários) e funcionamento (ou seja, funcionalidade de homogeneização) - é abordada em três capítulos diferentes. O primeiro capítulo testou o efeito do transporte marítimo internacional sobre a composição da assembleia de anfípodes ao longo da costa brasileira, usando códigos de barras de DNA, e explorou a possível falta de dados moleculares sobre esses crustáceos por meio de uma gap analysis. No estudo de caso do segundo capítulo, a propagação e as origens nativas putativas de dois habitantes comuns de comunidades do fouling ao redor do mundo - os anfípodes Jassa marmorata e Jassa slatteryi - foram avaliadas por meio da análise de DNA barcoding mitocondrial. No terceiro capítulo, as assembleias de anfípodes associadas ao fouling, em quatro estuários do Sul e Sudeste do Brasil, foram analisadas em diferentes aspectos de sua diversidade (taxonômica, filogenética e funcional). Para tanto, análises network, índices de estrutura de comunidades (diversidade alfa) e medidas de diversidade beta foram aplicadas para detectar possíveis efeitos de sazonalidade e potenciais impactos antrópicos. Além disso, uma nova espécie de anfípode e uma nova associação entre diatomáceas e anfípodes foram descritas no decorrer do desenvolvimento desta tese (publicações anexadas). Esta tese destaca que o fouling vágil, exemplificado aqui por crustáceos anfípodes, pode ser usada como ferramenta eficiente para detectar impactos humanos. No entanto, considerando as informações moleculares e taxonômicas, ainda há uma grande lacuna de conhecimento sobre esta comunidade artificial que precisa ser abordada para se adequar ao gerenciamento de possíveis novos impactos aos habitats naturais.Abstract: Substratos artificiais imersos em ambientes marinhos e estuarinos são, em geral, rapidamente colonizados por uma comunidade incrustante (fouling) que é conhecida por diminuir a flutuabilidade das bóias, obstruir dutos e afetar a hidrodinâmica dos barcos. No entanto, a fauna vágil do fouling ainda é comparativamente pouco estudada. As comunidades do fouling foram reconhecidas como stepping-stones para as espécies introduzidas não nativas (NIS), que, ao chegarem nos portos, também podem se espalhar para habitats naturais próximos. A principal hipótese desta tese - de que a proximidade de portos afeta negativamente as comunidades do fouling em sua composição (mais NIS perto dos portos), estrutura (proteção de barreiras ambientais entre estuários) e funcionamento (ou seja, funcionalidade de homogeneização) - é abordada em três capítulos diferentes. O primeiro capítulo testou o efeito do transporte marítimo internacional sobre a composição da assembleia de anfípodes ao longo da costa brasileira, usando códigos de barras de DNA, e explorou a possível falta de dados moleculares sobre esses crustáceos por meio de uma gap analysis. No estudo de caso do segundo capítulo, a propagação e as origens nativas putativas de dois habitantes comuns de comunidades do fouling ao redor do mundo - os anfípodes Jassa marmorata e Jassa slatteryi - foram avaliadas por meio da análise de DNA barcoding mitocondrial. No terceiro capítulo, as assembleias de anfípodes associadas ao fouling, em quatro estuários do Sul e Sudeste do Brasil, foram analisadas em diferentes aspectos de sua diversidade (taxonômica, filogenética e funcional). Para tanto, análises network, índices de estrutura de comunidades (diversidade alfa) e medidas de diversidade beta foram aplicadas para detectar possíveis efeitos de sazonalidade e potenciais impactos antrópicos. Além disso, uma nova espécie de anfípode e uma nova associação entre diatomáceas e anfípodes foram descritas no decorrer do desenvolvimento desta tese (publicações anexadas). Esta tese destaca que o fouling vágil, exemplificado aqui por crustáceos anfípodes, pode ser usada como ferramenta eficiente para detectar impactos humanos. No entanto, considerando as informações moleculares e taxonômicas, ainda há uma grande lacuna de conhecimento sobre esta comunidade artificial que precisa ser abordada para se adequar ao gerenciamento de possíveis novos impactos aos habitats naturais
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