Question

Which fish group includes parasites?​

Answer 1

I'm pretty sure the answer is the fish group called Agnatha, which includes parasitic fish like lamprey and the hagfish.

Step-by-step explanation:

Answer 2

some include nematodes, Platyhelminthes, leeches, parasitic crustaceans such as isopods and copepods, so also various microorganisms such as myxosporidia and microsporidia. (coral reef fish)