Scyphozoans are marine invertebrates, and can be found in every ocean in the world, and contains about 200 species, which mostly appear as medusae (jellyfish).

Although Scyphozoans have both asexual polyps and sexual medusa stages in their life cycles, medusa stage is dominant in the life cycle of this group

Their digestive system is incomplete since the same orifice (mouth) is used to take in food and expel waste.

Tentacles carry poisons that cause severe pain or death. Each tentacle is covered with cells called cnidocytes, that can sting or kill other animals. Most jellyfish use these cells to secure prey or for defense

 

The developmental stages of jellyfish