Sea wasp

The sea wasp is the deadliest animal in the world. They are pale blue and transparent and are difficult to see.

It is a kind of box jellyfish known as chironex fleckeri. Its tentacles are loaded with hundreds of thousands of microscopic stinging cells that inject a cobra-like venom.

This is so toxic that a person can die within five minutes of brushing against its trailing tentacles.  

The venom from a single creature can kill up to 60 adults! Over 100 people have been killed by the stings from a Chironex fleckeri