Figure 21. Geographic distribution of Botryocyrtis scutum. 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 and Riedel (1987); B, Boltovskoy (1999); C, Petrushevskaya (1971); D, Petrushevskaya (1971).