Dear Colleagues, We'd like to draw your attention to our new paper "*Interspecific Introgression in Cetaceans: DNA Markers Reveal Post-F1 Status of a Pilot Whale*", which was recently published in PLOS ONE. The abstract is below and the article can be found at: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0069511 - ABSTRACT: Visual species identification of cetacean strandings is difficult, especially when dead specimens are degraded and/or species are morphologically similar. The two recognised pilot whale species (*Globicephala melas* and *Globicephala macrorhynchus*) are sympatric in the North Atlantic Ocean. These species are very similar in external appearance and their morphometric characteristics partially overlap; thus visual identification is not always reliable. Genetic species identification ensures correct identification of specimens. Here we have employed one mitochondrial (D-Loop region) and eight nuclear loci (microsatellites) as genetic markers to identify six stranded pilot whales found in Galicia (Northwest Spain), one of them of ambiguous phenotype. DNA analyses yielded positive amplification of all loci and enabled species identification. Nuclear microsatellite DNA genotypes revealed mixed ancestry for one individual, identified as a post-F1 interspecific hybrid employing two different Bayesian methods. From the mitochondrial sequence the maternal species was *Globicephala melas*. This is the first hybrid documented between *Globicephala melas* and *G. macrorhynchus*, and the first post-F1 hybrid genetically identified between cetaceans, revealing interspecific genetic introgression in marine mammals. We propose to add nuclear loci to genetic databases for cetacean species identification in order to detect hybrid individuals. - Interspecific Introgression in Cetaceans: DNA Markers Reveal Post-F1 Status of a Pilot Whale<http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0069511> . Miralles L, Lens S, Rodríguez-Folgar A, Carrillo M, Martín V, et al. (2013) Interspecific Introgression in Cetaceans: DNA Markers Reveal Post-F1 Status of a Pilot Whale. PLoS ONE 8(8): e69511. doi:10.1371/journal.pone.0069511 - All the best, Laura Miralles M.Sc.Marine Biodiversity and Conservation Departamento Biología Funcional Universidad de Oviedo, España.