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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.
- Against all odds: a tale of marine range expansion with maintenance of extremely high genetic diversityPublication . Robalo, Joana; Francisco, Sara M.; Vendrell, Catarina; Lima, Cristina S.; Pereira, Ana; Brunner, Benedikt P.; Dia, Mamadou; Gordo, L. S.; Castilho, RitaThe displacement of species from equatorial latitudes to temperate locations following the increase in sea surface temperatures is among the significant reported consequences of climate change. Shifts in the distributional ranges of species result in fish communities tropicalisation, i.e., high latitude colonisations by typically low latitude distribution species. These movements create new interactions between species and new trophic assemblages. The Senegal seabream, Diplodus bellottii, may be used as a model to understand the population genetics of these invasions. In the last decades, this species has undergone an outstanding range expansion from its African area of origin to the Atlantic coast of the Iberian Peninsula, where now occurs abundantly. Mitochondrial and nuclear markers revealed a striking high haplotypic nucleotide and genetic diversity values, along with significant population differentiation throughout the present-day geographical range of the Senegal seabream. These results are not consistent with the central-marginal hypothesis, nor with the expectations of a leptokurtic distribution of individuals, as D. bellottii seems to be able to retain exceptional levels of diversity in marginal and recently colonised areas. We discuss possible causes for hyperdiversity and lack of geographical structure and subsequent implications for fisheries.