Fig. 1

The 11 world regions used for the biogeographical analysis (adapted from the system of Spalding et al. 2007, see text) (TNEP temperate Northeast Pacific, ALSK Alaska, ARCT Arctic, TNWA temperate Northwest Atlantic, TNEA temperate Northeast Atlantic, OKHO Okhotsk Sea, JAPK Japan, Korea, TSAM temperate South America, SOCE Southern Oceans, TSAF temperate South Africa, AUST Australasia)