1."Box jellyfish" or "sea wasp" are common names for the notoriously dangerous Chironex fleckeri.
Although the box jellyfish has been called "the world's most venomous creature", only a few species in the class have been confirmed to be involved in human deaths, and some species pose no serious threat at all.
2.The king cobra (Ophiophagus hannah)
The king cobra (Ophiophagus hannah) is the world's longest venomous snake, with a length up to 18.5 to 18.8 ft (5.6 to 5.7 m).This species, which preys chiefly on other snakes, is found predominantly in forests from India through Southeast Asia.
3.Conus marmoreus, common name the "marbled cone".
Conus marmoreus, is a species of predatory sea snail, a marine gastropod mollusk in the family Conidae, the cone snails, cone shells or conesThis species occurs in the Indian Ocean along Chagos and Madagascar, in the Bay of Bengal along India; in the western part of the Pacific Ocean to Fiji and the Marshall Islands.
4.Blue-ringed octopuses (genus Hapalochlaena)
The blue-ringed octopuses (genus Hapalochlaena) are three (or perhaps four) octopus species that live in tide pools and coral reefs in the Pacific and Indian Oceans, from Japan to Australia (mainly around southern New South Wales and South Australia). They are recognized as some of the world's most venomous marine animals.
5. Death Stalker Scorpion (Leiurus quinquestriatus).
The deathstalker (Leiurus quinquestriatus), is a species of scorpion, a member of the Buthidae family.The deathstalker is regarded as a highly dangerous species because its venom is a powerful mixture of neurotoxins, with a low lethal dose. While a sting from this scorpion is extraordinarily painful, it normally would not kill an otherwise healthy adult human.
Synanceia is a genus of fish of the family Synanceiidae, the Stonefishes, whose members are venomous, dangerous, and even fatal to humans. It is one of the most venomous fish currently known in the world.They are found in the coastal regions of Indo-Pacific oceans as well as off the coast of Florida and in the Caribbean.
7.The Brazilian wandering spider (Phoneutria).
Phoneutria, commonly known as Brazilian wandering spiders, armed spiders ("armadeiras", as they are known in Portuguese), or banana spiders (not to be confused with the relatively harmless Nephila), are a genus of aggressive and venomous spiders of potential medical significance to humans. They are mainly found in tropical South America, with one species in Central America.
8.Inland taipan (Oxyuranus microlepidotus).
The inland taipan (Oxyuranus microlepidotus), also commonly known as the small-scaled snake and fierce snake, is a species native to Australia and is regarded as the most venomous land snake in the world based on LD50 values in mice.It is a species of taipan belonging to the Elapidae family.The inland taipan consumes mostly rodents, other small mammals, and birds.
9.Poison Dart Frog ,Poison arrow frog.
Poison dart frog (also dart-poison frog, poison frog or formerly poison arrow frog) is the common name of a group of frogs in the family Dendrobatidae which are native to Central and South America. These species are diurnal and often have brightly colored bodies. Although all wild dendrobatids are at least somewhat toxic, levels of toxicity vary considerably from one species to the next and from one population to another.
10.Puffer Fish (Tetraodontidae).
Tetraodontidae is a family of primarily marine and estuarine fish of the order Tetraodontiformes.Pufferfish are generally believed to be the second-most poisonous vertebrates in the world, after the golden poison frog. Certain internal organs, such as liver, and sometimes the skin, are highly toxic to most animals when eaten; nevertheless, the meat of some species is considered a delicacy in Japan (as 河豚, pronounced as fugu), Korea (as bok), and China (as 河豚 hétún) when prepared by chefs who know which part is safe to eat and in what quantity.