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The presence of the opal chimaera, Chimaera opalescens, is reported for the first time in the deep waters of the Azores, with the capture of four specimens by fishermen and the video recording of an additional five individuals. Species identification was supported by the 646 bp sequenced fragment of the mitochondrial gene cytochrome oxidase subunit I. Because C. opalescens is a recently recognised species that had been recurrently misidentified as rabbitfish, Chimaera monstrosa, the historical data of C. monstrosa in the Azores were reviewed to assess the possible presence of both Chimaera species in the region. Although several authors have reported the occurrence of C. monstrosa in the Azorean waters since the 1800s, the majority of these are based on only three specimens caught during the late 1800s. The investigation performed using literature and examination of the museum specimens still available concluded that the most likely scenario is that C. monstrosa is absent from the Azores and past records of that species in the region are most likely misidentifications of C. opalescens. [ABSTRACT FROM AUTHOR]

Abstract: Comparative phylogeography for the commercially valuable deep-sea fish Aphanopus carbo from a large area of the NE Atlantic revealed remarkable patterns of concordance using two mtDNA markers. Two strongly supported phylogroups were identified from complete sequences of the control region (731–733bp) and partial sequences of cytochrome b (414bp) In one of these groups, all sequences from the Mid-Atlantic Ridge (Faraday seamount), mainland Portugal and Madeira were clustered together. The other group constituted all the sequences from the southern coast of Pico island (Azores, central group). The remaining sampling localities had sequences represented in both phylogroups. Although the two clades were strongly differentiated (Φ ST =0.8281 for the CR and Φ ST =0.9083 for the cytb) no evidence for any geographical pattern in this structure, was found. Historical demography of the mitochondrial control region was analysed to clarify the phylogenetic signals embedded in each phylogroup. Mismatch distributions for both clades suggested that both phylogroups were in agreement with sudden expansion models, and both with similar time estimates of expansion (τ =4.30 and τ =3.45 for phylogroup one and two, respectively). A molecular clock based on cytb sequences was enforced and dating of divergence for the two phylogroup was 412.5KY, a time that coincides with geological events that might have caused a split in the original population of black scabbardfish. Once climatic conditions and sea level were restored, the two separate populations came into contact again, leaving traces of the historical events in the non-recombinant mtDNA genes. An alternative hypothesis suggested is that two species of scabbardfish are present. The outcome from the comparison of the same mtDNA regions of the closely related Aphanopus intermedius from Angola clustered with the ones from phylogroup two (from the southern coast of Pico island, Azores). Therefore, these two species may have overlapping distribution ranges and are found sympatrically in the Azores. [Copyright &y& Elsevier]

The sand goby Pomatoschistus minutus is a major component of marine shelf and estuarine food webs and an important study organism in behavioural research. Yet, despite the sand goby’s significance, its past and present patterns of migration and gene flow are poorly understood. Here we use the mtDNA control region and parts of the flanking tRNA genes of 63 fish from six localities in the Adriatic (Eastern Mediterranean), Western Mediterranean, Atlantic, and North Sea to investigate the phylogeography of this gobiid. Phylogenetic analyses and population genetics statistics reveal the existence of an Evolutionarily Significant Unit, sensu Moritz (1994), in the Adriatic and another in the Western Mediterranean, Atlantic, and North Sea. A possible biogeographical scenario for the separation of the ancestral population is that sand gobies in the Adriatic and Western Mediterranean split between 10,000 and 5000 years ago when due to the rise in sea temperature they migrated northwards and were bisected by the Italian peninsula. A testable prediction of this scenario is that sand gobies from the Western Mediterranean, Adriatic, and Aegean form three reciprocally monophyletic groups which are the descendants of a three-way diversification event. [Copyright &y& Elsevier]