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- Molecular and morphological validation of the species of the genus Actinia (Actiniaria: Actiniidae) along the Atlantic Iberian PeninsulaPublication . Pereira, Ana; Cadeireiro, Emília; Ocaña, Oscar; Vukic, Jasna; Šanda, Radek; Mirimin, Luca; Robalo, Joana IsabelThe discrimination between the several species of the genus Actinia occurring in the Northeastern Atlantic and Mediterranean has been made analyzing morphological characters, with emphasis on external coloration patterns and morphology of cnidom structures. In Iberia, the occurrence of more than two species of Actinia has been suggested, but its validity is yet to be confirmed. In this paper, the identity of the species of the genus Actinia occurring along the Atlantic Iberian coast is investigated, analyzing morphological and molecular procedures. For this purpose, genetic data was collected from 140 individuals and two genetic markers were amplified and sequenced (the nuclear 28S and the mitochondrial 16S ribosomal genes). The genetic identification was corroborated by morphological analysis of individuals representing each of the genetic groups found. This procedure led to the identification of three species occurring in the studied area – Actinia equina (L.), A. fragacea Tugwell and A. schmidti Monteiro, Sole-Cava & Thorpe.
- Three mitochondrial lineages and no Atlantic-Mediterranean barrier for the bogue Boops boops across its widespread distributionPublication . Cunha, Regina L.; BEN FALEH, Abderraouf; Francisco, Sara; Šanda, Radek; Vukic, Jasna; Corona, Luana; DIA, Mamadou; Glavicic, Igor; Kassar, Abderrahmane; Castilho, Rita; Robalo, JoanaMarine species exhibiting wide distributional ranges are frequently subdivided into discrete genetic units over limited spatial scales. This is often due to specifc life-history traits or oceanographic barriers that prevent gene fow. Fine-scale sampling studies revealed distinct phylogeographic patterns in the northeastern Atlantic and the Mediterranean, ranging from panmixia to noticeable population genetic structure. Here, we used mitochondrial sequence data to analyse connectivity in the bogue Boops boops throughout most of its widespread distribution. Our results identifed the existence of three clades, one comprising specimens from the Azores and eastern Atlantic/Mediterranean, another with individuals from the Canary Islands, Madeira and Cape Verde archipelagos, and the third with samples from Mauritania only. One of the branches of the northern subtropical gyre (Azores Current) that drifts towards the Gulf of Cádiz promotes a closer connection between the Azores, southern Portugal and the Mediterranean B. boops populations. The Almería-Oran Front, widely recognised as an oceanographic barrier for many organisms to cross the Atlantic-Mediterranean divide, does not seem to afect the dispersal of this benthopelagic species. The southward movement of the Cape Verde Frontal Zone during the winter, combined with the relatively short duration of the pelagic larval stage of B. boops, may be potential factors for preventing the connectivity between the Atlantic oceanic archipelagos and Mauritania shaping the genetic signature of this species.
- Genetic hypervariability of a Northeastern Atlantic venomous rockfishPublication . Francisco, Sara M.; Castilho, Rita; Lima, Cristina S.; Almada, Frederico José Oliveira de; Rodrigues, Francisca; Šanda, Radek; Vukic, Jasna; Pappalardo, Anna Maria; Ferrito, Venera; Robalo, JoanaBackground: Understanding the interplay between climate and current and historical factors shaping genetic diversity is pivotal to infer changes in marine species range and communities’ composition. A phylogeographical break between the Atlantic and the Mediterranean has been documented for several marine organisms, translating into limited dispersal between the two basins. Methods: In this study, we screened the intraspecific diversity of 150 individuals of the Madeira rockfish (Scorpaena maderensis) across its distributional range (seven sampling locations in the Atlantic and Mediterranean basins) using the mitochondrial control region and the nuclear S7 first intron. Results: The present work is the most comprehensive study done for this species, yielding no genetic structure across sampled locations and no detectable Atlantic-Mediterranean break in connectivity. Our results reveal deep and hyper-diverse bush-like genealogies with large numbers of singletons and very few shared haplotypes. The genetic hyper-diversity found for the Madeira rockfish is relatively uncommon in rocky coastal species, whose dispersal capability is limited by local oceanographic patterns. The effect of climate warming on the distribution of the species is discussed.