The Sea Slug Atlas started on iSpot and migrated to iNaturalist.

However, iNaturalist has more sophisticated tools, and if you are interested in Sea Slugs, why not join this project, and we can transfer all future updates, reports, summaries and news to here::
https://www.inaturalist.org/projects/nudibranchs-and-sea-slugs-of-southern-africa

Southern African SeaSlugs are cool.

There are over 75 species in False Bay and the Peninsula alone, and many more going into tropical waters, and astute divers may be able to see 20 species on one dive in False Bay.

The biggest group - the Nudis Nudibranchs (= naked gills) comprise six suborders in our waters:

• Doridina Dorids
• Dendronotina Sheathslugs
• Dexiarchia Veilslugs
• Arminina
• Aeolidina Frilly Seaslugs, Aeolids
• Euctenidiacea

Other orders of Seaslugs include:

• Cephalaspidea Headshield Seaslugs
• Anaspidea Seahares
• Sacoglossa Sapsucking Seaslugs
• Pleurobranchida Sidegill Seaslugs (part of the old Notaspidea)

Find out more about Seaslugs here http://en.wikipedia.org/wiki/Opisthobranchia

There are some cool Sea Slug lookalikes. The most prominent group are the Marine Flatworms (Polycladida)