Chiropsalmus quadrumanus
Chiropsalmus quadrumanus, commonly known as the four-handed box jellyfish, is a species of box jellyfish found in the western Atlantic Ocean, the Gulf of Mexico and the Pacific Ocean. The sting is venomous and dangerous to humans, especially children.
Rhopilema nomadica
Rhopilema nomadica, the nomad jellyfish, is a jellyfish indigenous to tropical warm waters of the Indian and Pacific Oceans. Since 1970's it has been also found in Mediterranean Sea, where it entered via the Suez Canal. It has been found in the Eastern Mediterranean, off the coast of Israel, Turkey and in the Aegean Sea off the coast of Greece. "R. nomadica"'s body is light blue and the bell is rounded. It can grow up to 10 kg of weight, and its bell is commonly 40–60 cm in diameter, but can be up to 90 cm. European Union lists it as one of the worst invasive marine species in European waters.