Someone here mentioned this one long time ago. This is Bargibant's #Seahorse (Hippocampus bargibanti) and they are really small and hide on some coral species with similar colours. I drew it much bigger than real size so it can be visible.
Mastodon is the best way to keep up with what's happening.
Follow anyone across the fediverse and see it all in chronological order. No algorithms, ads, or clickbait in sight.