It is often difficult to distinguish between different species based on morphological attributes alone because these can vary both environmentally and developmentally. In recent years DNA barcoding has been used extensively to distinguish between many problematic species. This approach relies on the use of short segments of the genome of a species as a species identifier, in a similar way to the UPC product codes that can be scanned at the local supermarket. Comparison with barcodes from known species can be used as identifiers. Barcodes without a match are added to the database and can be used to identify closely related species.
This is the approach that Taite, et al. use in their article in the new issue of Biology and Environment: Proceedings of the Royal Irish Academy to distinguish between deep sea octopods belonging to the genera Muusoctopus and Bathypolypus, which are known for their high degree of morphological plasticity and where the number of species is still uncertain. Based on 298 specimens collected on deep water cruises and associated surveys between 2005–19, the authors identified nine deep sea octopod species and provide new information on the distribution of the two genera in the Northeast Atlantic. Five species were assigned to the genus Bathypolypus, and three species were assigned to the genus Muusoctopus, including one newly identified species. This research not only improves our understanding of the systematics of deep-sea octopods; it should also contribute to a better understanding of evolutionary relationships among the cephalopods.
The article DNA barcoding reveals unexpected diversity of deep-sea octopuses in the Northeast Atlantic, by M. Taite, L. Dillon, J.M. Strugnell, J. Drewery and A.L. Allcock, is available open access. Open access funding for this was provided by IReL.
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