On the modern distribution of the euryhaline species Cyprideis torosa (Jones, 1850) (Crustacea, Ostracoda)

The modern distribution of the euryhaline ostracod Cyprideis torosa (Jones, 1850) is illustrated on three geographical maps, visualizing its occurrence in Europe, Africa and Asia. The presence of other Cyprideis species, within the distribution area of C. torosa, is discussed. The species has also been recorded from Australia, but it appears now that its presence and that of other Cyprideis species, is a complex issue, that requires new research. Passive transport by migratory birds is briefly dealt with, by mentioning some interesting new examples from the literature, and by linking the distribution in China to the Central Asian Flyway of waterfowl. Cyprideis torosa is a single, highly variable, polymorphic and widely distributed species, with locally different populations. This variability is commented upon and put in a broader context. An imaginary line, connecting the peripheral records, delineates the distribution area of the species. The most interesting aspect is the very pronounced north–south distribution. The species occurs above the Arctic Circle in Europe and Asia but also in South Africa, illustrating that it is a eurythermal species that has adapted to very divergent temperature regimes.