Most jellyfish are more of an annoying nuisance than anything else. They tend to swarm and get in the way when you’re diving, and outside the occasional painful sting, they aren’t much of a bother.
The Amazonian Giant Centipede (Scolopendra gigantea) is one of the largest centipedes on the planet, reaching 12 inches (30 cm) in length.
Cone snails are common worldwide, and because of their brightly colored shells, they are highly prized by shell collectors.
Scorpions are always somewhat dangerous to humans, as their sting tends to come with a lot of pain. Still, they aren’t ordinarily deadly, but that’s not to say there aren’t a few capable of killing a person.
Most people don’t think of an octopus as a venomous creature since the main focus is usually on its eight legs. There are several venomous octopi, and the deadliest is, by far, the Blue-ringed octopus.
The Golden Poison Dart frog (Phyllobates terribilis) is the most poisonous animal in the world. The key word here is “poisonous,” as it has no venom of its own.
The Giant Silkworm Moth Caterpillar (Lonomia obliqua) is a saturniid moth species found in South America.
Several species of spiders are capable of killing folks, which is one reason arachnophobia is so prevalent.
Blue Sea Dragons (Glaucus atlanticus) are a species of sea slug known for their beautiful and unique shape, which resembles a dragon.
The Common Kingslayer (Malo Kingi) is a species of Irukandji jellyfish that is minuscule compared to larger animals such as the Australian Box Jellyfish.