Estep, in Estep et al. (1984: 618, figs 6, 7)
Leadbeater (1972b: figs 3–5), Hallegraeff (1983: 498, fig. 16, as Chrysochromulina sp. 1), LeRoi & Hallegraeff (2004: 83, figs 18, 19)
Cells spherical, 1.5–4 µm diameter (dried material, possibly up to twice as large when living), biflagellate; body covered with unmineralised body scales. Body scales of 2 types: both types circular, 0.2–0.4 µm diameter, with a cruciform central pattern surrounded by a 0.03 µm diameter central ring; one scale type with an additional raised ring near periphery and a radial pattern of 25–30 striae on one face; other scale type with a slightly raised rim and little or no patterning. Flagella slightly subequal, c. 11 and 13 µm long. Haptonema longer than flagella when extended, in 8–18 gyres when retracted.
Southern Ocean, south of Australia; North Atlantic (Estep et al., 1984); eastern Australia (Hallegraeff, 1983); Norway (Leadbeater, 1972b).
Chrysochromulina genus description: Cells have homodynamic flagella and a coiling haptonema, and electron microscopy is usually required to identify the species. As well as being photosynthetic, these fragile haptophytes ingest picoplanktonic and nanoplanktonic organisms by phagocytosis.