Suchergebnisse

13 páginas, 3 figuras, 1 tabla ; The black pygmy mussel Limnoperna securis (Lamarck 1819) is endemic to the brackish waters of New Zealand and Australia, but over the past decade, it has successfully invaded the inner Galician Rias of NW Spain. There is growing concern that L. securis will expand its range to the outer zones of the Rias, where it would pose a threat to the intensive raft culture of the indigenous mussel Mytilus galloprovincialis (Lamarck 1819). In this paper, we compare the valve-opening behaviour of the two mytilids under simulated raft conditions, i.e. full-strength seawater (35 g l−1) and a low current flow regime (2–5 cm s−1). Modes of valve-opening amplitudes that were most frequently observed in both species were in the range of 60–90 %, indicating a tendency towards full valve openness. Both species displayed circadian periodicity (τ = 24 h): maximal gaping was generally observed during periods of darkness and minimum gaping during daylight hours. The only prominent difference in behaviour between the two species was related to the degree of valve opening. The maximum recorded gape angle was 8.2° (SE = 0.9) for L. securis versus 14.8° (SE = 1.4) for M. galloprovincialis. This difference may place L. securis at a competitive disadvantage on substrates, where the two species coexist, such as over rocky shores or potentially mussel culture ropes ; This study was funded by the project AGL2010-16464 (Ministerio de Ciencia e Innovación, Spanish Government). ; Peer reviewed

9 páginas, 6 figuras, 4 tablas ; Marine organisms adapt to a wide variety of environments, often altering their morphology and behavior in response to local habitat. This study addressed the effects of habitat (wave exposure) and body size on the morphology and byssal attachment of mussels within the same estuary. Tenacity of the mussel Mytilus galloprovincialis was higher at the exposed site, particularly for the smaller size classes. This was largely due to differences in thread thickness; mussels from the exposed site produced thicker and stronger byssal threads. For a given shell length, exposed mussels also produced thicker and smaller shells and had lower gonadal condition. In laboratory flume experiments, both thread production and mechanical performance (strength and extensibility) decreased with increased flow, suggesting that flow alone does not explain tenacity differences between sites. Altogether, these analyses suggest that mussels at exposed sites allocate resources to reduce risk of dislodgment (smaller and thicker shell, stronger byssal threads) instead of growth and reproduction, and these allocation differences between sites are less apparent in larger size classes. The lack of the largest size class (8 cm) at the exposed site may reflect an upper limit to size imposed by wave induced mortality, where attachment strength does not keep pace with hydrodynamic loading. ; MF Babarro acknowledges the funding of the projects AGL2006-06986/ACU and AGL2010-16464 (Ministerio de Ciencia e Innovación, Spanish Government). ; Peer reviewed

The effect of the abiotic environment on byssus tenacity and associated features was investigated for Mytilus galloprovincialis in the Ría de Vigo (NW Spain). The effect of site was examined at macro-geographical (outer exposed Cabo Estay vs. inner sheltered San Simón Ensenada sites) and micro-geographical (intertidal vs. subtidal locations) scales. Site significantly influenced byssus tenacity, shape and byssus thread diameter, whereas location did not. Qualitative analysis of the byssus corroborated the importance of site; mussels inhabiting the rougher outer Ría secreted stronger and stiffer threads regardless of location and had a higher potential to form cross-links or metal chelation in the byssal collagen to gain structural integrity when needed. When mussels were transplanted between exposed and sheltered sites, asymmetrical changes were observed in tenacity, endogenous indices, byssus morphology and mechanical properties after 3 mo. Individuals transferred from the sheltered to the exposed site shifted all variables, suggesting that mussels have a plastic response to rougher environments by increasing byssus size and mechanical integrity. In contrast, mussels transplanted from the exposed to the sheltered site shifted tenacity, endogenous indices and thread length but not thread diameter nor mechanical properties. In summary, we report the highly dynamic nature of the mussel ability to modify byssus tenacity when subjected to abrupt environmental changes. Mussels have the potential to change byssus diameter and mechanical properties to increase strength in stressful abiotic conditions, and can re-allocate energy for vital structures such as gonadal and soft tissue growth in more benign environments ; This study was partly funded by "National Science Foundation EF1041213 to E. 600 Carrington. JMF Babarro acknowledges the funding of the projects AGL2006-06986/ACU and 601 AGL2010-16464 (Ministerio de Ciencia e Innovación, Spanish Government). 602 603 ; Peer reviewed

8 figuras, 2 tablas ; The impact of an alien species is correlated with its abundance and potential to colonise new environments. Consequently, the crucial aspects that give a mytilid species invasive potential include its strength and capacity for adhesion to a wide variety of substrates and its ecological tolerance to environmental conditions. The alien black pygmy mussel Xenostrobus securis settles together with the indigenous and raft cultured mussel Mytilus galloprovincialis on hard substrates of the inner coastline of the Ría de Vigo (Atlantic Coast NW Spain). Key parameters for the ecological success of these species could include their byssus structure and ecological plasticity. In this study, we assessed their comparative ability to attach to different substrates under different environmental conditions, using both in situ and laboratory approaches. Byssus threads secreted by X. securis were found to be extremely thin and their thickness did not vary with mussel size. This thinness of byssus filaments in X. securis was compensated by the secretion of a huge number (up to thousand of byssus filaments). Although no increase in attachment strength was found with increasing mussel size in this species, multiple byssus thread secretion might be a key factor in the successful invasion of inner areas of the estuary. Furthermore, X. securis exposes a much lower shell area to lift and drag forces in mussel conglomerates. By contrast, the indigenous species M. galloprovincialis secretes thicker byssus threads, which provide stronger in situ attachment displaying a linear increase in strength relative to the size of mussels. The exposure of both mytilid species to different abiotic factors in the laboratory confirmed the weaker byssus secretion and limited variation in attachment strength in the alien species. On one hand, X. securis seemed to be better adapted to life on soft bottoms and not capable of much plasticity when attached to different substrates. However, X. securis might be also well adapted to variable environmental conditions, e.g., salinity fluctuations, with no need to modify its byssus properties to ensure secure attachment. Attachment strength of M. galloprovincialis was higher than X. securis in all abiotic conditions tested. Results are discussed in relation to the ecological tolerance and impact of these mytilid species. ; This study was funded by the project AGL2010-16464 Dirección General de Investigación y Gestión del Plan Nacional de I+D+i (Ministerio de Ciencia e Innovación 2011–2013, Spanish Government). ; Peer reviewed

14 páginas, 1 apéndice, 5 tablas, 7 figuras ; The co-existence patterns of 2 mytilid species were studied in order to evaluate the performance of the alien mussel Xenostrobus securis and the indigenous Mytilus galloprovincialis through monospecific and mixed co-habiting experiments in the Ría de Vigo (northwest Spain). Mytilus galloprovincialis was found to be the best performer in all tests. Shell growth was ~4-fold greater for the indigenous mussel when deployed without interspecific competition and regardless of density. Differences in shell growth were found to be similar within mixed populations wherein M. galloprovincialis showed greater ability for upward migratory movements on the mixed beds and distanced itself from the mud influenced layer. The alien X. securis, however, was found to inhabit underneath the M. galloprovincialis layer, which resulted in higher mortality rates. Species-specific features such as byssus filaments and lifestyle may account for such different behaviour. M. galloprovincialis secreted thicker and stronger shells and byssus regardless of their density in both monospecific and mixed experiments. This might indicate that the indigenous mussel performs better when confronted with abiotic stress or biotic pressure. The alien X. securis is currently found to establish high-density patches of individuals at the confluence of main rivers that flow into the estuary (highly heterogeneous scenario). Such behaviour favours its settlement far from the native mussel influence area. X. securis also colonises hard substrates that are not-fully occupied by other invertebrates, but its range was found to be limited by the presence of the indigenous mussel. ; This study was funded by the project AGL2010-16464 (Ministerio de Ciencia e Innovación, Spanish Government). ; Peer reviewed

14 páginas, 7 figuras, 3 tablas ; The ability of the invasive mussel Xenostrobus securis to activate defence mechanisms in response to the novel predatory dogwhelk Nucella lapillus was explored using field- and laboratory-based approaches. The importance of the origin of mussels was investigated in relation to different environmental conditions and levels of predation pressure (high and low). In the field, the responses of mussels were clearly asymmetrical: only individuals caged with dogwhelks at the site of high predation risk underwent phenotypical changes (stronger attachment, thicker shells and heavier adductor muscle). In contrast, shell growth was faster in mussels held in cages without dogwhelks at the high predation-risk site, suggesting trade-off patterns between growth and other energy-demanding actions. Nevertheless, X. securis activated inducible morphological defences without any detrimental effect on soft tissue growth (i.e. condition index). In the laboratory, the role of temperature on phenotypic responses of mussels exposed to dogwhelk was also evaluated. Mussels originally from the site of low predation risk showed a weaker response to the predator N. lapillus, probably because of difficulties in correctly identifying predator cues. At higher temperatures, mussels secreted stronger byssal threads regardless of their origin, while condition was poorer, shells thinner and gametogenesis activated more rapidly, particularly in the presence of dogwhelks. In summary, X. securis appears to be highly capable of activating protective mechanisms in marine environments within its geographical range of expansion through improved fitness ; This study was funded by the Spanish government through the Ministerio de Ciencia e Innovación (project AGL2010-16464) and the Autonomic government Xunta de Galicia-FEDER (project GRC2013-004) ; Peer reviewed

7 pages, 3 tables, 5 figures.-- Under a Creative Commons license ; A number of trace elements (Mn, Fe, Co, Ni, Cu, Zn, As, Nb, Mo, Ag, Cd, Pb, U and the rare earth elements – REE) were analyzed in the dissolved phase, suspended particulate matter and in different organs (gills, hepatopancreas, and the rest of soft tissue) in mussels of the native Mytilus galloprovincialis and invasive Xenostrobus securis species in the Vigo Ria (NW Iberian Peninsula) in order to assess potential differences in their bioaccumulation patterns. Results obtained do not show significant differences in the bioaccumulation of trace elements by M. galloprovincialis and X. securis, except for Zn and Ag. In the case of Zn, a 4-fold enrichment in M. galloprovincialis compared to X. securis was found. The most important differences between species were observed for Ag, with approximately 40-fold higher concentrations in X. securis. Such elevated Ag bioaccumulation by X. securis can be useful for Ag biomonitoring using these invasive species in this area ; Funding was provided by the Spanish Government including European FEDER funds (project Ref. CTM2016-76146-C3-2-R) ; Peer reviewed

17 pages, 7 figures, 5 tables.-- This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) ; Estuarine environments are highly heterogeneous habitats where numerous organisms interact with each other. Aquaculture systems encompass such interactions, and the eventual yields depend on how the cultivated species respond to the environmental heterogeneity. Marine mussels are calcifying organisms that rely on calcium carbonate shell and byssus filaments secreted during their lifetime to protect soft vital tissues against aggressive (abiotic and biotic) environments. Nevertheless, these protective structures can be energetically costly, depending on the environment, thus affecting the energy allocation patterns in the organism. Consequently, other important fitness parameters for the aquaculture industry, such as soft tissue condition and market value, may also be affected. Here, we present a spatial and temporal analysis of the protective and soft tissues responses in the mussel Mytilus galloprovincialis with the aim of obtaining a better understanding of the inter-location variability in individual's performance and the corresponding main environmental drivers. Local environment with regard to food availability and hydrodynamics impact very distinctly mussel tenacity and shell thickening, e.g., higher-energy environments at the outer exposed zones caused individuals secreted stronger byssus and thicker shells. By contrast, the state of soft tissues (condition index) was similar between very distinct and distant outer exposed and inner sheltered zones due to differences in both environmental drivers. A novel, intuitive ecological index that measures the impact of both protective and soft tissues was developed and is discussed in relation to cultivation timing. The data presented provides the basis for understanding the natural variability in energetic requirements for different vital tissues in bivalve mollusk that support survival and growth. We report the scientific basis for management actions aimed to shortening the cultivation cycle in the aquaculture sector. These actions are based on the combined use of the PROFIT index and other aquaculture practices (e.g., modifying density). PROFIT helps to identify when the quality of the product, understood as PROtection and FITness strategies, would be best suited for the market ; This study was funded by the Spanish Government through the Ministerio de Economía y Competitividad through European FEDER funds (projects Ref. AGL-2013-45945-R, CTM2016-76146-C3-2-R/CTM2016-76146-C3-1-R) ; Peer reviewed

6 pages, 5 figures, 1 table.-- This is an open access article under the CC BY-NC-ND license ; We describe the valve-opening behavior of raft-cultivated mussels (Mytilus galloprovincialis) in the Ría de Arousa (Arousa estuary), Spain. Eight rope-grown mussels [mean ± standard error (SEM), shell length 61.6 ± 2.1 mm] were connected to a non-invasive valvometry apparatus that monitored (one measurement min−1) the magnitude of valve openness systematically over a 10 day period. It was found that valves were open 97.5 ± 1.3% percent of the time. Valve closures were not synchronized among the eight monitored mussels, suggesting that feeding cessation was physiologically-regulated rather than environmentally-mediated. The opening amplitudes that were most frequently observed were in the range of 60–90%, indicating that, when open, valves are usually opened relatively close to their maximum possible extent. The majority (7/8) of mussels displayed a circadian rhythm (τ = 24.0 h) in valve opening amplitude. They tended to exhibit maximum valve opening during nighttime and minimum opening during daytime. It is possible that the light:dark cycle represents an environmental zeitgeber entraining an endogenous gaping rhythm in this bivalve ; This study was funded by the Spanish government through the Ministerio de Economía y Competitividad (project Mytiga AGL2013- 45945-R) ; Peer reviewed

15 pages, 4 figures, 5 tables ; Properties of the shells and byssus filaments secreted by marine mussels are affected by environmental and biotic factors. In this study, we investigated the effects of pH and temperature on shell and byssus in artificially created monospecific and mixed aggregations of the indigenous mussel Mytilus galloprovincialis and the invasive mussel Xenostrobus securis. The variability in the response of the mussels was mainly explained by species-specific interactions derived from the type of aggregation. In the mixed groups, acidic conditions caused a decrease in byssus strength in M. galloprovincialis, but an increase in byssus strength in X. securis. Increased temperature positively affected shell strength in X. securis, but only in mixed aggregations. Interactive effects of acidification and warming were only detected in the organic matter of shells, the strength of which decreased in M. galloprovincialis in mixed aggregations. Although the invasive mussel may be able to take advantage of changed conditions by enhancing byssal attachment, the effects that acidification has on shells may make this species more vulnerable to some predators. The study findings provide some insight into the responses of protective and attachment structures of mussels to biotic and abiotic stressors, highlighting how species interactions may shape the future of mytilid populations ; This study was funded by the Spanish government through the Ministerio de Economía y Competitividad (projects AGL2013-45945-R and CTM2016- 76146-C3-2-R) and the Autonomic government Xunta de Galicia-FEDER (project GRC2013-004 ; Peer reviewed

16 pages, 4 figures, 2 tables.-- This is an Open Access article distributed under the terms of the Creative Commons Attribution License ; The impact of simulated seawater acidification and warming conditions on specimens of the mussel Mytilus galloprovincialis locally adapted to very distinct, widely separated sites in the Mediterranean Sea (Tunisia) and Atlantic Sea (Galicia, NW Spain) was evaluated in relation to key behavioural and eco-physiological parameters. Over the 2-month exposure to the experimental conditions, mussels were fed optimally to ensure that there are no synergistic interactions between climate change drivers and energetic status of the individuals. In general, regardless of origin (Atlantic or Mediterranean), the mussels were rather resilient to acidification for most of the parameters considered and they were able to grow in strongly acidified seawater through an increased feeding activity. However, shell strength decreased (40%) consistently in both mussel populations held in moderately and highly acidified seawater. The observed reduction in shell strength was not explained by slight alterations in organic matter, shell thickness or aragonite:calcite ratio. The combined effects of high acidification and warming on the key response of byssus strength caused a strong decline in mussel performance, although only in Galician mussels, in which the valve opening time decreased sharply as well as condition index (soft tissue state) and shell growth. By contrast, the observed negative effect of highly acidified scenario on the strength of Tunisian mussel shells was (partly but not totally) counterbalanced by the higher seawater temperature. Eco-physiological and behavioural interactions in mussels in relation to climate change are complex, and future scenarios for the ecology of the species and also the feasibility of cultivating them in Atlantic and Mediterranean zones are discussed ; This work was supported by the Spanish government through the Ministerio de Economía y Competitividad and European FEDER funds (AGL-2013-45945-R, CTM2016-76146-C3-2-R/CTM2016-76146-C3-1-R) and the Spanish National Research Council (CSIC) through the program I-COOP+ 2016 (ICOOPA20147 to J.L.) ; Peer reviewed

The carbon dioxide taken up by the ocean is increasing as levels of atmospheric carbon dioxide increase, thus lowering the ocean pH and altering the carbonate system. In this laboratory study, we evaluated the physiological responses of juvenile mussels Mytilus galloprovincialis from Galician waters (NW Iberian Peninsula) exposed to control (500 µatm) and elevated (800 or 1200 µatm) seawater pCO2 conditions under 2 different feeding regimes (optimal and suboptimal). Shell properties such as compressive strength and composition (organic matter and aragonite:calcite ratio) were negatively affected by high seawater pCO2, regardless of food availability. This result suggests that water chemistry is a main driver for shell development. Under the optimal feeding regime, mussel feeding rates increased in response to elevated pCO2, presumably as a strategy to maintain a high strength of attachment. In contrast, mussels on the suboptimal diet showed weak attachment and narrow valve opening at the highest pCO2 condition. Thus, our results suggest that with optimal food availability, mussels were resilient to water acidification with respect to feeding activity, valve opening and attachment strength. Under a suboptimal diet, however, the ability of mussels to respond to acidification was compromised. These results highlight complex ecophysiological interactions for calcifying organisms subjected to climate change ; This study was funded by the Spanish government through the Ministerio de Economía y Competitividad that included European FEDER funds (projects Ref. AGL-2013-45945-R, CTM2016-76146-C3-2-R/ CTM2016- 76146-C3-1-R). J.L. acknowledges funding from the Spanish National Research Council (CSIC) through the Program ICOOP+ 2016 (Ref. ICOOPA20147) ; Peer reviewed

2 pages.-- XV International Estuarine Biogeochemistry Symposium, Vigo, June 04-05 2019 ; Global environmental changes have been reported over the last years and their impact on organisms' behaviour has been studied. Recent studies already demonstrated that in marine systems the release of contaminants in association with predicted environmental changes (increase in CO2 and decrease in pH) may play a key role not only in the organisms' behavior but also on contaminants toxicity. Therefore, the aim of the present study is to assess the impact of oceanic acidification on the bioavailability of wellstudy metals (Cd, Cu, Pb, Ag) and emerging contaminants (Ce and Pt) and to understand if this environmental change will increase the adverse effects in aquatic environments, using mussels (M. galloprovincialis) as bioindicators. Metal treatments were done by a mixture of isotopically-labelled metals at realistic concentrations: 111Cd (80 ng/L), 65Cu (2 μg/L), 207Pb (200 ng/L), 109Ag (20 ng/L), 142Ce (20 ng/L) and 194Pt (2 ng/L). Two different seawater CO2 concentrations were selected: 400 ppm (current value) and 1200 ppm (estimated content for 2100) (IPCC, 2014). Mussels were exposed for 21 days at spikedseawater constant flow (9 ml/min), under control conditions (16ºC, 12:12 photoperiod) and with constant food addition (1:1, Rhodomonas:T-Iso) (1 mg/L). During the exposure period samples of seawater and phytoplankton were taken to determine metal content and isotopic composition. During the experimental period biological responses were measured by analyzing weekly filtration rates (PAMAS laser particle counter), and at the end of this period by measuring byssus strength. Biochemical responses were assessed by measuring mussel metabolic capacity, energy-related biomarkers, oxidative stress and neurotoxic status. Chemical analyses were done in mussel byssus, gills, feet, glands and soft bodies as well as in water samples. Expected results will help us to understand the influence of seawater acidification on the impacts of pollutants and sensitivity of mussels towards these pollutants, identifying possible synergistic effects ; Authors wish to acknowledge funding provided by Spanish government through the Ministerio de Economía y Competitividad (project ARIOS Ref. CTM2016-76146-C3-2-R/ CTM2016-76146-C3-1-R) and the post-doctoral position of A. Romero-Freire funded by the Ministry of Science, Innovation and Universities (FJCI-2016-28622). This work is a contribution to the COST Action TD1407 ; Peer reviewed

20 pages, 11 figures, 2 tables.-- This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) ; Estuarine exchange flow plays an important role in the biogeochemical properties exchange between the coastal ocean and the estuaries. Circulation patterns inside the Rias Baixas (NW Iberian Peninsula) have been widely studied, while the Ría de Pontevedra has received less attention. A high-resolution ROMS-AGRIF system configuration with three online two-way nesting domains was used and validated to enhance the knowledge about the circulation patterns of this Ría. Two representative estuarine circulation patterns were studied: a coastal upwelling event and a downwelling event associated with a maximum river runoff of 84 m3/s. An analysis using Empirical Orthogonal Functions (EOF) was applied to the horizontal subtidal velocity fields at the surface layer and at 20 m depth and to the subtidal normal velocity across vertical cross-sections. Upwelling events are characterized by a reinforcement of the positive estuarine circulation, in which the surface waters outflow and deep waters inflow at the main sill of the Ría, whilst full water column inflow (outflow) is observed at the northern (southern) openings. Conversely, downwelling events induce an opposite behavior, consisting of a negative estuarine circulation with the surface (deep) inflow (outflow) at the main sill of the Ría and outflow (inflow) at the northern (southern) openings. Evidences of a front splitting two vertical clockwise circulation cells were found. These cells are associated with the ocean water subduction that enters through the surface layer under downwelling favorable winds and this surface inflow opposes to the direction of the inner estuarine circulation. The EOF study confirms that shelf wind forcing has an important contribution to the variability of the velocity field, inducing positive or negative estuarine like circulation. The temporal principal components (PC) of EOF analysis present correlations of 0.92 between the meridional wind component and the first mode, and 0.77 between the zonal wind component and the second mode. Third EOF mode represents the circulation during transitional winds when some vorticity structures are visible. The realistic high-resolution simulation of the physical conditions at the Ría de Pontevedra provides new insights into the ocean-estuarine water exchanges and allow the visualization of recirculation processes and characteristic structures that have consequences in the marine ecosystem and in their productivity ; This study was performed in the framework of MYTIGA project (AGL2013-45945-R) supported by the Spanish government through the Ministerio de Economía y Competitividad. This work contributes to HABWAVE project (LISBOA-01-0145-FEDER-031265), and CESAM_LA (UIDP/50017/2020 + UIDB/50017/2020), funded by FCT/MEC through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. This work also contributes to MarRisk project (0262_MARRISK_1_E) co-funded by European Regional Development Fund (FEDER) in the framework of Interreg V A España – Portugal (POCTEP) 2014-2020 ; Peer reviewed

23 páginas, 6 figuras, 3 tablas.-- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited ; Different combinations of behavioural and physiological responses may play a crucial role in the ecological success of species, notably in the context of biological invasions. The invasive mussel Xenostrobus securis has successfully colonised the inner part of the Galician Rias Baixas (NW Spain), where it co-occurs with the commercially-important mussel Mytilus galloprovincialis. This study investigated the effect of a heatwave on the physiological and behavioural responses in monospecific or mixed aggregations of these species. In a mesocosm experiment, mussels were exposed to simulated tidal cycles and similar temperature conditions to those experienced in the field during a heat-wave that occurred in the summer of 2013, when field robo-mussels registered temperatures up to 44.5°C at low tide. The overall responses to stress differed markedly between the two species. In monospecific aggregations M. galloprovincialis was more vulnerable than X. securis to heat exposure during emersion. However, in mixed aggregations, the presence of the invader was associated with lower mortality in M. galloprovincialis. The greater sensitivity of M. galloprovincialis to heat exposure was reflected in a higher mortality level, greater induction of Hsp70 protein and higher rates of respiration and gaping activity, which were accompanied by a lower heart rate (bradycardia). The findings show that the invader enhanced the physiological performance of M. galloprovincialis, highlighting the importance of species interactions in regulating responses to environmental stress. Understanding the complex interactions between ecological factors and physiological and behavioural responses of closely-related species is essential for predicting the impacts of invasions in the context of future climate change ; This research was supported by the Autonomous government Xunta de Galicia-FEDER (GRC2013-004) and the Spanish government (AGL2010-16464 and AGL2013-45945-R). IG was supported by a pre-doctoral contract funded by the University of Vigo (P.P. 00VI 131H 64103). FPL ; Peer reviewed