Bloom forming and toxic phytoplankton in transitional and coastal waters of Cantabria region coast (Southeastern Bay of Biscay, Spain)

► The first description of phytoplankton community of some sites of the Bay of Biscay. ► Citation of the presence of toxic taxa never cited before in the area. ► Citation of bloom events in the estuaries and coast of the Cantabria region coast. ► Contribution to the knowledge of both toxic and bloom forming species distribution.