Left: School of jackfish. Right: Chub. Images via Shutterstock. This group is something of a catch-all, comprised of four species of reef-dwelling fish that are actually not at all related. However, these large, silver predators all look similar and can be easily confused for each other, so we’ve grouped them together. You may not be able to identify exactly which one of these four you’ve seen, but you’ll know it’s one of them by their long, silver bodies and forked tails.