Most jellyfish are poisonous. They have tentacles with special structures that can release venom. Generally, if you are stabbed by jellyfish, you will only feel burning pain and redness.
On the sea surface from Malaysia to Australia, there are two kinds of jellyfish called drag jellyfish and box jellyfish. Their secretion is very toxic. If they stab them, they will have difficulty breathing and die within a few minutes. Therefore, they are called killer jellyfish.
Jellyfish, also known as jellyfish, is a kind of jellyfish of the phylum cnidae, which is distributed in waters all over the world. They existed as early as 650 million years ago, and they appeared even earlier than dinosaurs.
The shape of jellyfish is like a transparent umbrella. The diameter of the umbrella is large and small. The diameter of the umbrella of large jellyfish can reach 2 meters. There are some whisker like tentacles on the edge of the umbrella, and some tentacles can be as long as 20-30 meters. Its body is mainly composed of water and consists of inner and outer germ layers. There is a thick mesogel layer between the two layers, which is not only transparent, but also floating.
All jellyfish are carnivorous animals. They feed on fish and plankton. But when hunting, jellyfish are very passive and only prey on animals swimming around them. They use stinging cells on their tentacles to sting or kill prey, and then send food to their mouths and digestive cavities. Most jellyfish are almost transparent, making it difficult for enemies to find. Some jellyfish can shine and attract prey with the faint light they emit.