Application of DNA barcoding for controlling of the species from Octopus genus

The DNA barcoding proposes the use of a particular sequence from a single genomic region as the base for an identifying system capable to determine all animal species. This methodology comprises the analysis of a 655 base-pair region from the mithocondrial cytochrome <em>C oxidase</em> gene (COI). Its application in the species identification of fishery products has been very promising. However, in the last years some doubts about its usage have emerged. In this work, we make use of the DNA barcoding for the identification of some of the octopus species with higher commercial interest (<em>Octopus membranaceus, Octopus vulgaris, Octopus aegina, Octopus cyanea</em>) focusing the attention on the reliability and completeness of the available information on the databases. The study looked over 51 individuals apparently belonging to the <em>Octopus</em> genus. For the identification of <em>O.aegina</em>, <em>O.cyanea</em>, <em>O.vulgaris</em> species no particular problems were found. On the other hand, most of the samples of <em>O.membranaceus</em>, though they clearly presented the morphological characteristics of the species, were not identified with the biomolecular analyses