Peacock Mantis Shrimp (Odontodactylus scyllarus)

Despite the name, Mantis Shrimp aren't shrimp at all — they're stomatopods, a separate crustacean order entirely, and they carry two genuinely remarkable pieces of biology for an invertebrate this size. Their eyes contain up to sixteen types of color receptors, compared to three in humans, giving them a visual system scientists still don't fully understand the purpose of, and their raptorial front claws strike with enough speed and force that larger species have been documented cracking aquarium glass. They're intelligent, engaging predators to observe, but genuinely incompatible with a community reef tank, since that same strike will make quick work of snails, crabs, and small fish alike. Species-specific housing only.