likely Pseudo-nitzchia fraudulenta.

Pseudo-nitzschia (Cleve) H.Peragallo 1900
Pseudo-nitschia seriata complex

Common in marine waters. Identification of the genus is fairly straightforward with light microscopy. However, differentiation of species is difficult without ultrastructural investigations (high R.I mount or EM). Cells should be identified as 'Pseudo-nitschia seriata complex' (pp. 101-103. Kraberg, A., Baumann, M., & Dürselen, C-D. (2010). Coastal Phytoplankton :
Photo Guide for Northern European Seas. p. 71. Verlag Dr. F. Pfeil. Munchen. And, p.110, Hoppenrath, M., Elbrächter, M. & Drebes, G. (2009). Marine phytoplankton Selected microphytoplankton species from the North Sea around Helgoland and Sylt. pp. [1]-264, figs 1-87. Stuttgart: E. Schweizerbart'sche Verlagsbuchhandlung.)

Specimen from a general plankton tow in Trincomali Channel, Galiano Island, B.C. Hitachi 4700 SEM, UBC BioImaging Facility. Many thanks to Elaine Humphrey for preparation and imaging assistance.