This highly distinctive species of Fucus stands out in the NW Atlantic flora with its serrate margins (Image A). We have genetically verified records from the upper intertidal to subtidal (10 m), typically on rock, and limited to the waters of Cape Breton, NS, the Northumberland Strait, NS (as well as specimens from the adjacent NB coast for which genetic work was not completed), and parts of PE. Recent (2020) collections were also made along the South Shore of NS. The limited distribution is likely a consequence of the relatively recent introduction of this species from Europe (Mathieson & Dawes 2017) combined with the unusually warm summer waters in the NW Atlantic where this species has established (adjacent waters may be to cold to facilitate further dispersal).
Image A. Specimen from the low-mid intertidal showing the serrated margins characteristic of this species (Cape Breton, NS; GWS002293).