The CIESM Atlas of Exotic Species is the first attempt to provide a comprehensive, group by group, survey of recent marine "immigrants" in the Mediterranean, which is undergoing drastic and rapid changes to its biota. Many of these new species are of Indo-Pacific origin having reached the Mediterranean Sea through the Suez Canal: these so called "Lessepsian" migrants now contribute significantly to the biodiversity of the Eastern basin. With increasing attention paid to this phenomenon, invaders of other origin-notably from the tropical Atlantic realm- are now more frequently recognized as well, a result of a natural invasion through the Gibraltar straits or of introduction (accidental or intentional) by man.
The Atlas is a guide for researchers, environmental planners and non-specialists who are interested in or likely to encounter marine species that are not native to the basin.