No pectoral or pelvic fins, only one dorsal, caudal and anal fin.
No scales, the body is covered with a protective mucus.
This moray eel is solitary, but it often stays with cleaning shrimp with which it shares its meals and offers protection in exchange for deworming.
The whale shark is the largest fish in the world!
Some whales are larger, but they are mammals, not fish!
Parrotfish create a protective envelope around them when they are sleeping.
So, don't put the light on them during night dive to don't to wake them up and break this envelope.
Some sharks can stay motionless on the sand (white tips reef sharks, nurse sharks, etc.).
These sharks don't have to swim to bring oxygen to their gills like other sharks (grey, hammerheads tc.)