Ghiozzos are created by directly infecting ordinary fish with the t-Abyss virus. Their appearance strongly resembles the deep-sea fish that originally carried the Abyss virus, the progenitor of the t-Abyss virus.
Because of the virus's influence, Ghiozzos had large appetites, sharp teeth, and strong jaws. A school of these ferocious B.O.W.s can eat through large mammals, bones and all, in a matter of seconds, similar to the famous (but mostly untrue) aggression of piranhas. Even worse, the Ghiozzo is now somewhat amphibious, able to move and attack on land to a certain extent - however, they are most effective in their natural aquatic environment.
BIOHAZARD REVELATIONS NAVIGATION & ART. Capcom. 2012. ISBN 978-4862333322.