Convict tangs are often found swimming in groups. Their scientific name is Acanthurus triostegus, and in Hawaii they’re called manini. They have sharp blades on the sides of their tail, which is the reason they’re also called surgeonfish; the blades pop out like knives when the fish is provoked, resembling a surgeon’s scalpel. And you can probably guess where “convict” came from- look at those black stripes!
In case you were wondering, the name “sea hare” is a direct translation from lepus marinus in Latin. In Hawaii they’re called kualakai.