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- Exploring the response of a key Mediterranean gorgonian to heat stress across biological and spatial scalesPublication . Gómez-Gras, D.; Bensoussan, N.; Ledoux, J. B.; López-Sendino, P.; Cerrano, C.; Ferretti, E.; Kipson, S.; Bakran-Petricioli, T.; A, Serrão; Paulo, D.; Coelho, Márcio; Pearson, Gareth; Boavida, J.; Montero-Serra, I.; Pagès-Escolà, M.; Medrano, A.; López-Sanz, A.; Milanese, M.; Linares, C.; Garrabou, J.Understanding the factors and processes that shape intra-specific sensitivity to heat stress is fundamental to better predicting the vulnerability of benthic species to climate change. Here, we investigate the response of a habitat-forming Mediterranean octocoral, the red gorgonian Paramuricea clavata (Risso, 1826) to thermal stress at multiple biological and geographical scales. Samples from eleven P. clavata populations inhabiting four localities separated by hundreds to more than 1500 km of coast and with contrasting thermal histories were exposed to a critical temperature threshold (25 degrees C) in a common garden experiment in aquaria. Ten of the 11 populations lacked thermotolerance to the experimental conditions provided (25 days at 25 degrees C), with 100% or almost 100% colony mortality by the end of the experiment. Furthermore, we found no significant association between local average thermal regimes nor recent thermal history (i.e., local water temperatures in the 3 months prior to the experiment) and population thermotolerance. Overall, our results suggest that local adaptation and/or acclimation to warmer conditions have a limited role in the response of P. clavata to thermal stress. The study also confirms the sensitivity of this species to warm temperatures across its distributional range and questions its adaptive capacity under ocean warming conditions. However, important inter-individual variation in thermotolerance was found within populations, particularly those exposed to the most severe prior marine heatwaves. These observations suggest that P. clavata could harbor adaptive potential to future warming acting on standing genetic variation (i.e., divergent selection) and/or environmentally-induced phenotypic variation (i.e., intra- and/or intergenerational plasticity).
- Ecossistemas de corais em águas continentais profundas portuguesasPublication . Oliveira, Frederico; Coelho, Márcio; Serrao, Ester; Gonçalves, Jorge Manuel SantosOs fundos marinhos de todo o planeta permanecem largamente inexplorados. Este livro aborda os ecossistemas de coral em águas profundas portuguesas.
- Fuzzy species limits in Mediterranean gorgonians (Cnidaria, Octocorallia): inferences on speciation processesPublication . Aurelle, Didier; Pivotto, Isabelle D.; Malfant, Marine; Topcu, Nur E.; Masmoudi, Mauatassem B.; Chaoui, Lamya; Kara, Hichem M.; Coelho, Márcio; Castilho, Rita; Haguenauer, AnneThe study of the interplay between speciation and hybridization is of primary importance in evolutionary biology. Octocorals are ecologically important species whose shallow phylogenetic relationships often remain to be studied. In the Mediterranean Sea, three congeneric octocorals can be observed in sympatry: Eunicella verrucosa, Eunicella cavolini and Eunicella singularis. They display morphological differences and E.singularis hosts photosynthetic Symbiodinium, contrary to the two other species. Two nuclear sequence markers were used to study speciation and gene flow between these species, through network analysis and Approximate Bayesian Computation (ABC). Shared sequences indicated the possibility of hybridization or incomplete lineage sorting. According to ABC, a scenario of gene flow through secondary contact was the best model to explain these results. At the intraspecific level, neither geographical nor ecological isolation corresponded to distinct genetic lineages in E.cavolini. These results are discussed in the light of the potential role of ecology and genetic incompatibilities in the persistence of species limits.
- Complete mitochondrial genome of the branching octocoral Paramuricea grayi (Johnson, 1861), phylogenetic relationships and divergence analysisPublication . Coelho, Márcio; Ledoux, Jean-Baptiste; Boavida, Joana; Paulo, Diogo; Gómez-Gras, Daniel; Bensoussan, Nathaniel; López-Sendino, Paula; Cerrano, Carlo; Kipson, Silvija; Bakran-Petricioli, Tatjana; Garrabou, Joaquim; A, Serrão; Pearson, GarethThe Gray's sea fan, Paramuricea grayi (Johnson, 1861), typically inhabits deep littoral and circalittoral habitats of the eastern temperate and tropical Atlantic Ocean. Along the Iberian Peninsula, where P. grayi is a dominant constituent of circalittoral coral gardens, two segregating lineages (yellow and purple morphotypes) were recently identified using single-copy nuclear orthologues. The mitochondrial genomes of 9 P. grayi individuals covering both color morphotypes were assembled from RNA-seq data, using samples collected at three sites in southern (Sagres and Tavira) and western (Cape Espichel) Portugal. The complete circular mitogenome is 18,668 bp in length, has an A + T-rich base composition (62.5%) and contains the 17 genes typically found in Octocorallia: 14 protein-coding genes (atp6, atp8, cob, cox1-3, mt-mutS, nad1-6, and nad4L), the small and large subunit rRNAs (rns and rnl), and one transfer RNA (trnM). The mitogenomes were nearly identical for all specimens, though we identified a noteworthy polymorphism (two SNPs 9 bp apart) in the mt-mutS of one purple individual that is shared with the sister species P. clavata. The mitogenomes of the two species have a pairwise sequence identity of 99.0%, with nad6 and mt-mutS having the highest rates of non-synonymous substitutions.
- Lipkea ruspoliana Vogt, 1886 (Cnidaria: Staurozoa) in Portugal: the contribution of citizen science to range extension and taxonomic discussion of rare speciesPublication . Miranda, Lucília S.; Tavares, Sílvia; dos Santos, Antonina; Gonçalves, Emanuel J.; Serrao, Ester; Coelho, MárcioCitizen science online platforms are increasingly making important sources of biological information available at the click of a button, allowing the interaction of volunteers and scientists to report and identify the world's diversity. In this work, we combined the data available in citizen science platforms (iNaturalist and GelAvista) and the effort and collaboration of a diverse team of scuba-divers, scientists, and underwater photographers to report for the first time the presence of the stauromedusa Lipkea (Cnidaria: Staurozoa) in Portugal. Based on DNA (COI and 16S), we identified the species as Lipkearuspoliana. However, the marginal lappets of some Portuguese specimens are similar to those of Lipkeasturdzii, a species described based on a single specimen in 1893 and never reported again. These results suggest that L.sturdzii is a synonym of L.ruspoliana, although further taxon and habitat sampling for genetic studies and investigations of intraspecific morphological variation are necessary. In addition, we provided data on species ecology, reviewed the records of Staurozoa from Portugal, and mapped the world geographic distribution of Lipkea. Staurozoa is a cryptic group of cnidarians, and Lipkea seems to be a particularly rare genus. Citizen science has proved to be a valuable contribution to studies on the group, enabling biological discussions that otherwise would be more challenging.
- High coral bycatch in bottom-set Gillnet Coastal fisheries reveals rich coral habitats in Southern PortugalPublication . Dias, Vítor; Oliveira, Frederico; Boavida, Joana; Serrao, Ester; Gonçalves, Jorge Manuel Santos; Coelho, MárcioBottom-contact fisheries are unquestionably one of the main threats to the ecological integrity and functioning of deep-sea and circalittoral ecosystems, notably cold-water corals (CWC) and coral gardens. Lessons from the destructive impact of bottom trawling highlight the urgent need to understand how fisheries affect these vulnerable marine ecosystems. At the same time, the impact of other fishing gear and small-scale fisheries remains sparsely known despite anecdotal evidence suggesting their impact may be significant. This study aims to provide baseline information on coral bycatch by bottom-set gillnets used by artisanal fisheries in Sagres (Algarve, southwestern Portugal), thereby contributing to understand the impact of the activity but also the diversity and abundance of corals in this region. Coral bycatch frequency and species composition were quantified over two fishing seasons (summer-autumn and spring) for 42 days. The relationship with fishing effort was characterized according to metiers (n = 6). The results showed that 85% of the gillnet deployments caught corals. The maximum number of coral specimens per net was observed in a deployment targeting Lophius budegassa (n = 144). In total, 4,326 coral fragments and colonies of 22 different species were captured (fishing depth range of 57-510 m, mean 139 +/- 8 m). The most affected species were Eunicella verrucosa (32%), Paramuricea grayi (29%), Dendrophyllia cornigera (12%), and Dendrophyllia ramea (6%). The variables found to significantly influence the amount of corals caught were the target species, net length, depth, and mesh size. The 22 species of corals caught as bycatch belong to Orders Alcyonacea (80%), Scleractinia (18%), Zoantharia (1%), and Antipatharia (1%), corresponding to around 13% of the coral species known for the Portuguese mainland coast. These results show that the impact of artisanal fisheries on circalittoral coral gardens and CWC is potentially greater than previously appreciated, which underscores the need for new conservation measures and alternative fishing practices. Measures such as closure of fishing areas, frequent monitoring onboard of fishing vessels, or the development of encounter protocols in national waters are a good course of action. This study highlights the rich coral gardens of Sagres and how artisanal fisheries can pose significant threat to corals habitats in certain areas.
- Routes of TBT uptake in the clam Ruditapes decussatus. I. Water and sediments as vectors of TBT uptakePublication . Coelho, Márcio; Bebianno, Maria João; Langston, W. J.This study assesses the relative importance of water and sediments as vectors of TBT uptake in the sediment-dwelling suspension feeder, Ruditapes decussatus. Accumulation of TBT was determined in R, decussatus exposed for 60 days to moderately high but environmentally realistic levels of TBT in water (100 ng Snl(-1)) and sediments (0.8 mug Sn g(-1) dw), separately or in combination, using constant-flow systems. The results indicate that this species accumulates TBT predominantly from water. Although some accumulation from sediments does occur. the processing of large amounts of water needed to sustain the filter-feeding habits of this species is a prime determinant of TBT uptake. The route of exposure is reflected in tissue distributions of TBT in R. decussatus. However, gills are the most important site for accumulation of TBT from water. irrespective of whether contaminated sediments are present or not.
- Organotin levels in the Ria Formosa lagoon, PortugalPublication . Coelho, Márcio; Bebianno, Maria João; Langston, W. J.Organotin concentrations were measured in water, sediments and clams (Ruditapes decussatus) from 11 sites in the Ria Formosa lagoon, Portugal, in 1992-93. Results showed a marked spatial pattern of tributyltin (TBT) and dibutyltin concentrations. The highest organotin concentrations were observed at Olhao (site 5), where the most important fishing harbour of the Southern coast of Portugal is located. Results indicated that fishing vessels, moored in the harbour at Olhao (site 5), were the major source of organotin contamination to the lagoon. No significant seasonal trend was observed, suggesting a continuous input of organotin compounds throughout the year. In several areas of the lagoon the TBT burdens in R. decussatus could have deleterious developmental effects
- Not out of the Mediterranean: Atlantic populations of the gorgonian Paramuricea clavata are a separate sister species under further lineage diversificationPublication . Coelho, Márcio; Pearson, Gareth; Boavida, Joana R. H.; Paulo, Diogo; Aurelle, Didier; Arnaud‐Haond, Sophie; Gómez‐Gras, Daniel; Bensoussan, Nathaniel; López‐Sendino, Paula; Cerrano, Carlo; Kipson, Silvija; Bakran‐Petricioli, Tatjana; Ferretti, Eliana; Linares, Cristina; Garrabou, Joaquim; Serrão, Ester A.; Ledoux, Jean‐BaptisteThe accurate delimitation of species boundaries in nonbilaterian marine taxa is notoriously difficult, with consequences for many studies in ecology and evolution. Anthozoans are a diverse group of key structural organisms worldwide, but the lack of reliable morphological characters and informative genetic markers hampers our ability to understand species diversification. We investigated population differentiation and species limits in Atlantic (Iberian Peninsula) and Mediterranean lineages of the octocoral genus Paramuricea previously identified as P. clavata. We used a diverse set of molecular markers (microsatellites, RNA-seq derived single-copy orthologues [SCO] and mt-mutS [mitochondrial barcode]) at 49 locations. Clear segregation of Atlantic and Mediterranean lineages was found with all markers. Species-tree estimations based on SCO strongly supported these two clades as distinct, recently diverged sister species with incomplete lineage sorting, P. cf. grayi and P. clavata, respectively. Furthermore, a second putative (or ongoing) speciation event was detected in the Atlantic between two P. cf. grayi color morphotypes (yellow and purple) using SCO and supported by microsatellites. While segregating P. cf. grayi lineages showed considerable geographic structure, dominating circalittoral communities in southern (yellow) and western (purple) Portugal, their occurrence in sympatry at some localities suggests a degree of reproductive isolation. Overall, our results show that previous molecular and morphological studies have underestimated species diversity in Paramuricea occurring in the Iberian Peninsula, which has important implications for conservation planning. Finally, our findings validate the usefulness of phylotranscriptomics for resolving evolutionary relationships in octocorals.
- Phylogeography and phylogeny of european gorgoniids (Gorgoniidae: genera Eunicella and LeptogorgiaPublication . Coelho, Márcio; Aurelle, DidierAs gorgónias, antozoários marinhos (Sub-classe Octocorallia) ubiquamente distribuídos por todo o mundo, são importantes e amplamente conhecidas por acolherem vastas comunidades de organismos associados. Tipificadas pela sua arquitectura arborescente, as gorgónias possuem um esqueleto axial de origem proteica (gorgonina) que confere suporte às colónias e pode ser de diferentes naturezas. Apesar da sua incontestável importância ecológica, a taxonomia e relações filogenéticas das gorgónias, e octocorais na generalidade, são alvo de aceso debate e pouco consenso entre taxonomistas. Na verdade, até o reconhecimento de limites taxonómicos ao nível das espécies é complicado e muitas espécies são subdivididas em sub-espécies ou variantes locais ao longo de amplas escalas geográficas. Na base desta controvérsia taxonómica estão diversos factores entre os quais: a variabilidade inter e intra-específica dos caracteres morfológicos usados na identificação das espécies, homoplasia e falta de caracteres morfológicos diagnosticantes adequados; ausência de registos fósseis; resolução limitada dos marcadores moleculares usados até á data ao nível das espécies; e baixos níveis de variabilidade dos genes mitocondriais nos octocorais.