 This is supported by the existences of current endemic, oceanic species such as lagoon cockles which was genetically identified to originate in Caspian/Black Seas regions.The sea's basin (including associated waters such as rivers) has 160 native species and subspecies of fish in more than 60 genera.About 62% of the species and subspecies are endemic, as are 4–6 genera (depending on taxonomic treatment).