Figure 9. Geographic distribution of Acanthosphaera actinota. N: total number of positive records [total number of samples where the species was presumably sought], for water-column (above 150 m and below 150 m; plankton and sediment trap materials) and surface sediment materials. Sources: A, Boltovskoy (1999); B, Popofsky (1913); C, Original; D, Original.