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  • High genetic differentiation of red gorgonian populations from the Atlantic Ocean and the Mediterranean Sea
    Publication . Pilczynska, Joanna; Cocito, Silvia; boavida, joana; A, Serrão; Queiroga, Henrique
    Patterns of genetic variation within a species may be used to infer past events in the evolutionary history of marine species. In the present study we aimed to compare the genetic diversity of the red gorgonian Paramuricea clavata in the Atlantic Ocean and the Mediterranean Sea. For genetic markers we used microsatellites and a mitochondrial gene fragment. Our results revealed a distinct genetic composition and diversity between the Mediterranean and the Atlantic. The Mediterranean samples had higher microsatellite heterozygosity, allelic richness and private allelic richness. The hypotheses that can explain these patterns are the isolation of Atlantic populations and/or a founder effect. Additionally, a clear difference was obtained from the mitochondrial locus, since sequences from Atlantic and Mediterranean samples diverged by 1%, which is high for soft corals.
  • Low clonal propagation in Atlantic and Mediterranean populations of the red gorgonian Paramuricea clavata (Octocorallia)
    Publication . Pilczynska, Joanna; Boavida, Joana; Cocito, Silvia; Lombardi, Chiara; Peirano, Andrea; Queiroga, Henrique
    Clonal propagation is a common feature of benthic marine organisms. In the present study, we investigated the contribution of clonal reproduction in the red gorgonian Paramuricea clavata. Mediterranean populations of P. clavata were severely affected by mass mortality events caused by increased water temperature in 1999 and 2003. The populations are characterized by slow growth and episodic recruitment, but after the observed mortalities, an unexpectedly high recovery rate was observed in the severely affected populations from the Ligurian Sea, NW Mediterranean. Ten years after the last mortality event, we investigated the contribution of clonal propagation in populations from the Ligurian Sea, where some populations were highly affected by mass mortality events, and from the Atlantic, where mortality was never observed. All individuals were genotyped for nine microsatellite loci. The contribution of clonal reproduction varied from 0% to 13% and did not differ significantly between affected and unaffected populations. We confirm by using genetic markers that clonal propagation in P. clavata is not common, and that the contribution of clones is too low to play an important role in red gorgonian reproduction and cannot contribute to population recovery at sites that have been affected by mass mortality events.
  • A well-kept treasure at depth: precious red coral rediscovered in Atlantic deep coral gardens (SW Portugal) after 300 years
    Publication . Boavida, Joana; Paulo, Diogo; Aurelle, Didier; ARNAUD-HAOND, Sophie; Marschal, Christian; Reed, John; Gonçalves, J. M. S.; Serrão, Ester
    The highly valuable red coral Corallium rubrum is listed in several Mediterranean Conventions for species protection and management since the 1980s. Yet, the lack of data about its Atlantic distribution has hindered its protection there. This culminated in the recent discovery of poaching activities harvesting tens of kg of coral per day from deep rocky reefs off SW Portugal. Red coral was irregularly exploited in Portugal between the 1200s and 1700s, until the fishery collapsed. Its occurrence has not been reported for the last 300 years.