Cosmopolitism, rareness and endemism in deep-sea marine nematodes

Nematodes represent the most abundant benthic metazoan of all seas and oceans, their relative importance increases with increasing water depth. Understanding biodiversity patterns this dominant phylum could be a critical step towards our comprehension evolutionary across largest biome biosphere. For instance, it has been assumed for long time that nematodes are ubiquitous depths, latitudes biogeographic regions, but there is still little scientific evidence lack endemism. The present study based on meta-analysis nematode data collected from 246 deep-sea sites Atlantic Ocean Mediterranean Sea. We explored cosmopolitanism, rareness potential endemism genera in sediments. results analysis indicate only one-third families widely distributed potentially cosmopolitan, whereas 94% linked to specific habitats or bathymetric ranges. Singleton (i.e. presenting as single individual one habitat) increased conclude may far more common feature than previously thought assemblages hypothesise deep ocean interior huge reservoir endemic species.