I have broken up the invertebrate life into things (mostly) with eyes, and things without. Behold, the things without eyes…
Sponges
The Mediterranean has a history of sponge diving that goes back to antiquity, and we saw quite a variety of sponges, but not vast numbers of them. The Mediterranean bath sponge is the primary target of sponge divers, and comes in a variety of exterior hues. It’s apparently creamy yellow to beige inside.