See: Zookeys. 2014; (399): 43–69.

First, determine which species you're interested in. Second, find out which countries they occur in. Third, search for papers, such as the one above, which will tell you about their distributions. You can also do your own field work using transect-quadrats, dredges, and direct searches. The latter technique is preferable because it shows the actual numbers.

I hope this helps!

You have to identify the species and use publications, inclusive historical ones, for the distribution records of this species. The better way you consult with specialists if the record is new or seemingly new.

You have to take care with synonymy (same species might be mentioned under various names).

First determination. Second see site WORMS for bibliography and distribution Best wishes YG

I concur with Yves Gruet - Worms is World Register of Marine Species - marinespecies.org

Thank you all for you suggestions and time, it's help me a lot.