About Seaweed are immensely varied and beautiful. Regrettably, they can also be very difficult to identify in the field, the depth of the problem only fully appreciated in the light of contemporary DNA barcoding. The intent with these pages is not to provide a comprehensive account for each species, however, it is hoped that these pages will serve as a guide to check identifications determined through the various keys that are available; notably Gabrielson & Lindstrom (2018) for British Columbia and Sears (2002) for the northwest Atlantic and, to a lesser extent, Canadian Arctic. Additional information on the North Atlantic species can be found in the comprehensive publications of Taylor (1962; a must have work; consult AlgaeBase for name updates (Guiry & Guiry 2020)), Bird & McLachlan (1992; red algae) and Mathieson & Dawes (2017). Where the potential occurs for confusion between various genetic groups that manifest as a single morphospecies, comments will be provided. Distribution is indicated following each species’ name as BC (British Columbia), Ar (Arctic) and A (Atlantic), and while the emphasis is on the Canadian flora, information on the contiguous American waters is provided in the text.

Accessing Species Pages: Species pages can be viewed by entering a genus or species name into the search window below. Or can be browsed taxonomically by major seaweed group: Chlorophyta (green algae), Phaeophyceae (brown algae), Phaeosacciophyceae (false brown algae) or Rhodophyta (red algae).

Additional Resources: Nomenclatural and taxonomic notes, including name changes and a comprehensive listing of synonyms, can be obtained by searching a species name found here in the wonderful online resource AlgaeBase. For more images of each species, similarly search in the Taxonomy Browser at the Barcode of Life Data System, but be careful as all images may not be correctly assigned (typically those starting with ‘GWS’ are from our group and at least match the species as presented here).

Disclaimer & Limitations: This is, and will remain, a work in progress both in terms of the overall flora, and the individual species pages. I would ask for your patience as I slowly upload and update the many species pages. The intent is to provide baseline information at first for all species, and then build substance to the species pages as time permits. All users are responsible for researching and questioning everything that is provided here. This is one algal taxonomist’s opinion and interpretation of the literature and species that have been studied. Reviewing the primary literature and any other pertinent resources always remain the responsibility of the reader. Enjoy!

Acknowledgements: The various morphological, ecological and geographical comments, as well as many of the images, derive from decades of fieldwork by my Laboratory group. No person is an island and none of this would have been possible without a long and fulfilling career mentoring the next generation of phycologists. This continuous stream of young and energetic minds have empowered me to complete this work through their friendship and tireless dedication to their work. Of particular note my Laboratory Manager Tanya Moore has had a significant impact on the lab’s research output for more than a decade! This work is dedicated to all of them, in addition to my loving family who have had to endure endless absences on my part. I wonder at times if they feel that I like my work more than them – that simply isn’t the case. To Dolores, Karsten and Davin, for all that you have endured and your unwavering support, my sincerest thanks and deepest love. Although this page is not directly supported, specimens used in completing this project were secured through many years of projects funded by the University of New Brunswick (UNB), the Natural Sciences and Engineering Research Council of Canada, Canada Research Chair program, the Canadian Barcode of Life Network from Genome Canada through the Ontario Genomics Institute, as well as other sponsors listed at, with infrastructure support from the Canada Foundation for Innovation and New Brunswick Innovation Foundation. All sources are gratefully acknowledged for variously supporting research in the Saunders Laboratory since 1995.

Citing Seaweed of Canada: Saunders, G.W. 2023. The Seaweed of Canada: guide pages to assist with species confirmation.; searched <date searched>.

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Copyright & Intellectual Property: Copyright and other intellectual property rights worldwide are attributed to Gary W. Saunders.


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