A DNA barcode examination of the Laminariaceae (Phaeophyceae) in Canada reveals novel biogeographical and evolutionary insights

Abstract

McDevit D.C. and Saunders G.W. 2010. A DNA barcode examination of the Laminariaceae (Phaeophyceae) in Canada reveals novel biogeographical and evolutionary insights. Phycologia 49: 235–248. DOI: 10.2216/09-36.1

DNA barcoding is becoming a widely applied tool for the rapid and accurate identification of eukaryotic species. In this study we used the DNA barcode for large-scale screening of the brown algal family Laminariaceae in Canada. With the examination of 194 COI-5P (5′ end of cytochrome c oxidase 1) sequences (150 newly determined) from representatives of this family, we confirmed the presence of 12 species in Canadian waters (Cymathaere triplicata, Laminaria digitata, L. ephemera, L. setchellii, L. solidungula, L. yezoensis, Macrocystis integrifolia, Nereocystis leutkeana, Postelsia palmaeformis, Saccharina groenlandica, S. latissima and S. sessilis). Saccharina groenlandica, a species with a history of taxonomic confusion, was found in the Pacific, Hudson Bay (subarctic) and Atlantic Canada extending greatly our comprehension of the biogeography of this species. Additionally, COI-5P data from S. latissima, combined with ITS results, provided insights into historical distributional patterns and uncovered a hybridization zone between incipient species in this complex. These discoveries highlight how the growth of a worldwide barcode database for the assignment of individuals to genetic species will uncover new perspectives on biogeography and species diversity on a global scale.

Key Words::

• Barcode
• Biogeography
• Cytochrome c oxidase I
• Kelp
• Laminariaceae
• Mucilage ducts
• Saccharina groenlandica
• Saccharina latissima

ACKNOWLEDGMENTS

We would like to thank the colleagues listed in Table 1 for their assistance with collections, as well as Katrina McKay for laboratory assistance. This research was supported through funding to the Canadian Barcode of Life Network from Genome Canada (through the Ontario Genomics Institute), and other sponsors listed at www.BOLNET.ca. Additional funding was provided by the Canada Research Chair Program, the Natural Science and Engineering Research Council of Canada, the Canada Foundation for Innovation and the New Brunswick Innovation Foundation grants to GWS.