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- Not so sluggish : The success of the Felimare picta complex (Gastropoda, Nudibranchia) crossing Atlantic biogeographic barriersPublication . Almada, Frederico José Oliveira de; Levy, André; Robalo, Joana IsabelThe molecular phylogeny of the Atlanto-Mediterranean species of the genus Felimare, particularly those attributed to the species F. picta, was inferred using two mitochondrial markers (16S and COI). A recent revision of the Chromodorididae clarified the taxonomic relationships at the family level redefining the genus Felimare. However, conflicting taxonomic classifications have been proposed for a restrict group of taxa with overlapping morphological characteristics and geographical distributions designated here as the Felimare picta complex. Three major groups were identified: one Mediterranean and amphi-Atlantic group; a western Atlantic group and a tropical eastern Atlantic group. F. picta forms a paraphyletic group since some subspecies are more closely related with taxa traditionaly classified as independent species (e.g. F. zebra) than with other subspecies with allopatric distributions (e.g. F. picta picta and F. picta tema). Usually, nudibranchs have adhesive demersal eggs, short planktonic larval phases and low mobility as adults unless rafting on floating materials occurs. Surprisingly however, the phylogeny of the F. picta complex suggests that they successfully cross main Atlantic biogeographic barriers including the mid-Atlantic barrier. This ability to cross different biogeographic barriers may be related to F. picta's distinct life history and ecological traits. Compared to other Chromodorididae F. picta has larger eggs and planktotrophic larvae which could be related to a longer planktonic phase.
- Citizen science and expert judgement: A cost-efficient combination to monitor and assess the invasiveness of non-indigenous fish escapeesPublication . Parretti, Paola; Monteiro, João Gama; Gizzi, Francesca; Martinez-Escauriaza, Roi; Alves, Filipe; Chebaane, Sahar; Almeida, Silvia; Pais, Miguel Pessanha; Almada, Frederico José Oliveira de; Fernandez, Marc; Nogueira, Natacha; Andrade, Carlos; Canning-Clode, JoãoMapping the distribution and evaluating the impacts of marine non-indigenous species (NIS) are two fundamental tasks for management purposes, yet they are often time consuming and expensive. This case study focuses on the NIS gilthead seabream Sparus aurata escaped from offshore farms in Madeira Island in order to test an innovative, cost-efficient combined approach to risk assessment and georeferenced dispersal data collection. Species invasiveness was screened using the Aquatic Species Invasiveness Screening Kit (AS-ISK), and revealed a high invasion risk. Occurrences of S. aurata were assessed involving citizens in GIS participatory mapping and data from recreational fishing contests. A probability map showed that S. aurata is well dispersed around Madeira Island. This assessment proved to be a cost-efficient early warning method for detecting NIS dispersal, highlighting the urgent need for additional surveys that should search for sexually mature individuals and assess the direct and indirect impacts in the native ecosystem
- Exploring bioactivities and peptide content of body mucus from the lusitanian toadfish Halobatrachus didactylusPublication . Cunha, Marta Fernandez; Coscueta, Ezequiel; Emilia Brassesco, M.; Marques, Rita; Neto, José; Almada, Frederico José Oliveira de; Goncalves, David; Pintado, Maria ManuelaIdentifying bioactive molecules from marine organisms is still vastly understudied. Fish remain an untapped source of bioactive molecules, even when considering species whose toxicity to other fish species has been noticed before. We assessed potential applications of crude body mucus of the Lusitanian toadfish (Halobratachus didactylus) and characterized its peptide fraction composition. Mucus samples from three individuals (two wild and one captive) revealed potential antioxidant, antihypertensive, and antimicrobial activities. For antioxidant activity, the best results of 2371 ± 97 µmol Trolox Equivalent/g protein for ORAC and 154 ± 6 µmol Trolox Equivalent/g protein for ABTS were obtained. For antihypertensive activity, the relevant inhibitory activity of ACE resulted in IC50 of 60 ± 7 µg protein/mL. Antimicrobial activity was also identified against the pathogenic bacteria Escherichia coli and Listeria monocytogenes. The peptide profile of the crude body mucus was obtained through size exclusion chromatography, with a conspicuous peak at ca. 800 Da. LC-MS/MS allowed the detection of the most probable peptide sequences of this dominant peptide. This is the first study where the bioactive potential of mucus from the Lusitanian toadfish is demonstrated. Peptides with such properties can be applied in the food and pharmaceutical industries.
- Northern refugia and recent expansion in the North Sea: The case of the wrasse Symphodus melops (Linnaeus, 1758)Publication . Robalo, Joana Isabel; Castilho, Rita; Francisco, Sara Martins; Almada, Frederico José Oliveira de; Knutsen, Halvor; Jorde, Per Erik; Pereira, Ana Martins; Almada, Vítor CarvalhoPleistocene climate changes have imposed extreme conditions to intertidal rocky marine communities, forcing many species to significant range shifts in their geographical distributions. Phylogeographic analyses based on both mitochondrial and nuclear genetic markers provide a useful approach to unravel phylogeographic patterns and processes of species after this time period, to gain general knowledge of how climatic changes affect shifts in species distributions.We analyzed these patterns on the corkwing wrasse (Symphodus melops, Labridae), a rocky shore species inhabiting North Sea waters and temperate northeastern Atlantic Ocean from Norway toMorocco including theAzores, using a fragment of the mitochondrial control region and the first intron of the nuclear S7 ribosomal protein gene.We found that S. melops shows a clear differentiation between the Atlantic and the Scandinavian populations and a sharp contrast in the genetic diversity, high in the south and low in the north. Within each of these main geographic areas there is little or no genetic differentiation. The species may have persisted throughout the last glacial maximum in the southern areas as paleotemperatures were not lower than they are today in North Scandinavia. The North Sea recolonization most likely took place during the current interglacial and is dominated by a haplotype absent from the south of the study area, but present in Plymouth and Belfast. The possibility of a glacial refugium in or near the English Channel is discussed.
- A revision of the status of Lepadogaster lepadogaster (Teleostei: Gobiesocidae): Sympatric subspecies or a long misunderstood blend of species?Publication . Henriques, Miguel; Lourenço, Rita; Almada, Frederico José Oliveira de; Calado, Gonçalo; Gonçalves, David; Gillemaud, Thomas; Cancela, M. Leonor; Almada, Vítor CarvalhoMolecular (partial mitochondrial 12S ribosomal DNA sequences), morphological and meristic analysis of Lepadogaster lepadogaster lepadogaster, L. l. purpurea and L. zebrina were performed to investigate the relationships between these taxa. On the western shore of mainland Portugal, where the two subspecies of L. lepadogaster occur sympatrically, they differ in microhabitat preferences and their breeding seasons are largely out of phase. This information, combined with data on distribution patterns, led to the following conclusions: Lepadogaster l. purpurea is considered to be a valid species, L. purpurea (Bonnaterre, 1788), different from L. l. lepadogaster, now designated L. lepadogaster (Bonnaterre, 1788). L. zebrina was found to be a synonym of L. lepadogaster. The two newly defined species were found to be in sympatry at Madeira and the Canary islands, the Atlantic coast of the Iberian Peninsula, and the Mediterranean at least as far as Genoa (Italy). Diagnostic characters and a list of synonyms are provided.
- Cryptic effects of biological invasions: Reduction of the aggressive behaviour of a native fish under the influence of an "invasive" biomoleculePublication . Magliozzi, Laura; Almada, Frederico José Oliveira de; Robalo, Joana Isabel; Mollo, Ernesto; Polese, Gianluca; Gonçalves, Emanuel João; Felline, Serena; Terlizzi, Antonio; D'Aniello, BiagioThe invasive green alga Caulerpa cylindracea has become an important component of the diet of the Mediterranean white seabream Diplodus sargus. As a consequence of this ªexotic dietº, the algal bisindolic alkaloid caulerpin accumulates in the fish tissues. Although the compound shows structural similarity to endogenous indolamines that modulate animal behaviour, the potential impact of caulerpin on fish behaviour still remains unexplored. In this report, behavioural experiments both on groups and on single fish responding towards a mirror were performed under different doses of dietary caulerpin. Differences between treated and control groups for each behaviour and for the overall aggressive pattern during the different experimental phases showed that the aggressiveness of D. sargus decreased with the administration of caulerpin. These results call the attention to a still unexplored potential ability of bioactive metabolites from marine invasive species, to alter the behaviour on native species, with putative negative effects on patterns of fish growth and population dynamics
- Historical gene flow constraints in a northeastern atlantic fish: Phylogeography of the ballan wrasse labrus bergylta across its distribution rangePublication . Almada, Frederico José Oliveira de; Francisco, Sara Martins; Lima, Cristina Silva; Fitzgerald, Richard; Mirimin, Luca; Villegas-Ríos, David; Saborido-Rey, Fran; Afonso, Pedro; Morato, Telmo; Bexiga, Sérgio; Robalo, Joana IsabelThe distribution and demographic patterns of marine organisms in the north Atlantic were largely shaped by climatic changes during the Pleistocene, when recurrent glacial maxima forced them to move south or to survive in northern peri-glacial refugia. These patterns were also influenced by biological and ecological factors intrinsic to each species, namely their dispersion ability. The ballan wrasse (Labrus bergylta), the largest labrid fish along Europe's continental margins, is a target for fisheries and aquaculture industry. The phylogeographic pattern, population structure, potential glacial refugia and recolonization routes for this species were assessed across its full distribution range, using mitochondrial and nuclear markers. The existence of a marked population structure can reflect both recolonization from three distinct glacial refugia and current and past oceanographic circulation patterns. Although isolated in present times, shared haplotypes between continental and Azores populations and historical exchange of migrants in both directions point to a common origin of L. bergylta. This situation is likely to be maintained and/or accentuated by current circulation patterns in the north Atlantic, and may lead to incipient speciation in the already distinct Azorean population. Future monitoring of this species is crucial to evaluate how this species is coping with current environmental changes.
- Reclassification of Lepadogaster candollei based on molecular and meristic evidence with a redefinition of the genus LepadogasterPublication . Almada, Frederico José Oliveira de; Henriques, Miguel; Levy, André; Pereira, Ana Martins; Robalo, Joana Isabel; Almada, Vítor CarvalhoInexistente
- On the absence of genetic differentiation between morphotypes of the ballan wrasse Labrus bergylta (Labridae)Publication . Almada, Frederico José Oliveira de; Casas, Laura; Francisco, Sara Martins; Villegas-Ríos, David; Saborido-Rey, Fran; Irigoien, Xabier; Robalo, Joana IsabelThe ballan wrasse, Labrus bergylta (Labridae), is a protogynous hermaphrodite fish common in the north-eastern Atlantic from Norway to Morocco. It is a commercially important resource for local fisheries and is currently being used as cleaner fish to control sea lice in salmon farms in northern Europe. Two distinct colour patterns have been recently reported in the literature: plain and spotted. These individuals follow strikingly different life history strategies raising the question of whether they represent one or two independent taxonomic units. Analyses of mitochondrial (18S, COI and control region) and nuclear (S7) markers revealed no genetic differences between these morphotypes. Alternative explanations for the origin and persistence of distinct morphotypes are discussed.
- Effect of the algal alkaloid caulerpin on neuropeptide Y (NPY) expression in the central nervous system (CNS) of Diplodus sargusPublication . Magliozzi, Laura; Maselli, Valeria; Almada, Frederico José Oliveira de; Di Cosmo, Anna; Mollo, Ernesto; Polese, GianlucaRecent studies have suggested that Mediterranean indigenous fish species are affected by bioactive metabolites coming from marine invasive species via food web interactions. In particular, both physiological and behavioural changes in the white sea bream Diplodus sargus were related to caulerpin (CAU), a bisindolic alkaloid particularly abundant in the invasive alga Caulerpa cylindracea, on which the fish actively feed. Dietary administration of CAU decreased aggressiveness in D. sargus, suggesting an anxiolytic-like effect of CAU possibly mediated by endogenous anxiolytic agents. This hypothesis is supported here by the finding of a significant increase of NPY transcriptional expression in the brain of fish fed with CAU enriched food, shedding more light on the neural mechanisms behind the altered behaviour of D. sargus.