Cantina marsupialis (Larsen and Patterson 1990) Yubuki et al. 2015 (Figs 2q, 3d)

Cells are 7–8 μm long, 6–5 μm wide and D-shaped. The anterior flagellum is 1.5–2 times the cell length and directed normal to a deep ventral groove. The posterior flagellum lies in the ventral groove and is slightly longer than the cell. The cells attach to the substrate via the tip of the posterior flagellum. A single nucleus with a rounded nucleolus lies just below the insertion of the flagella. The cell body may or may not include many – sometimes large – food vacuoles. Description based on observations of 18 cells. Occurance: every month at Acı Lake, temperature 1–23.5 °C, salinity 24–67.5 psu, dissolved oxygen 3.75–13.2 mg /L.

Remarks: Yubuki et al. (2015) carried out an ultrastructural and molecular study which demonstrates that Cafeteria marsupialis should be re-named at the genus level since it is not in the same clade with the species of the genus Cafeteria. Thus, they established the new genus Cantina with the type species Cantina marsupialis. The genus Cantina resembles Cafeteria in having a D-shaped cell body, an anterior flagellum drawing water towards the cell body and a posterior flagellum adhering to the substrate by its tip, but differs from Cafeteria by having a large ventral groove and a posteriorly curved food ingestion region. Cantina marsupialis was reported in Australia, Brazil, United Kingdom, Japan, Canada and Rusia (White Sea) (Larsen and Patterson 1990, Ekebom et al. 1996; Tong 1997b, c; Tong et al. 1997, Lee and Patterson 1998, Lee et al. 2003; Lee 2006b, 2019; Tikhonenkov et al. 2006, Yubuki et al. 2015).