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This paper examines the distribution of 91 modern dinoflagellate cyst taxa from 3636 locations across the world's oceans. Patterns of distributions among the taxa included bipolarity, cosmopolitan, northern versus southern hemispheres, and geographically restricted. Of the 91 taxa, three dominate these assemblages at the global scale, Brigantedinium species, Operculodinium centrocarpum sensu Wall and Dale 1966 and some species of Spiniferites. Whereas Brigantedinium is a true cosmopolitan taxon, with high abundances in each ocean, Operculodinium centrocarpum sensu Wall and Dale 1966 shows high abundances in polar to temperate regions in the Northern Hemisphere, and in tropical to subtropical waters in the Southern Hemisphere. Spiniferites species show highest occurrences in the Southern Hemisphere. This study also highlights three true bi-polar species, Impagidinium pallidum, Islandinium minutum and Polarella glacialis. Only a few taxa are strictly endemic, either being relics of ancient seas such as the Paratethys (Spiniferites cruciformis) or linked to specific environmental conditions. However, recent studies have shown recent worldwide dispersal of these endemic species possibly due to human activities. Overall, this compilation has highlighted the progress made since the early 1970s on our understanding of these important tracers of environmental conditions but also gaps in our knowledge of their distribution in pelagic regions in the Pacific and Indian Oceans as well as under Arctic sea ice.

2020) Are concentrations of pollutants in sharks, rays and skates (Elasmobranchii) a cause for concern? A systematic review. Marine Pollution Bulletin, 160. p. 111701.

Ghana is one of the top pesticide users and highest persistent organic pollutant (POP) emitters in sub-saharan Africa. Despite recent increases in published data, there is limited information on how POP concentrations have changed, post ratification of the Stockholm Convention. As a result, this review aims to address these knowledge gaps by collating available data that reported POPs in Ghanaian environmental matrices, identify spatial and temporal trends, and establish potential health risks. It is worth noting that Ghana has not developed its own