Box jellyfish
Although the notoriously dangerous species of box jellyfish are largely restricted to the tropical Indo-Pacific region, various species of box jellyfish can be found widely in tropical and subtropical oceans, including the Atlantic Ocean and the east Pacific Ocean, with species as far north as California ("Carybdea confusa"), the Mediterranean Sea ("Carybdea marsupialis") and Japan (such as "Chironex yamaguchii"), and as far south as South Africa (for example, "Carybdea branchi") and New Zealand (such as "Copula sivickisi").
Chrysaora hysoscella
The compass jellyfish (Chrysaora hysoscella) is a very common species of jellyfish that lives in coastal waters of the Atlantic and Mediterranean, including near the United Kingdom, Ireland and Turkey. It is also known from the southern Atlantic Ocean from the west coast of South Africa and False Bay It has a diameter of up to 30 cm. Its 24 tentacles are arranged in eight groups of three. It is usually colored yellowish white, with some brown. It usually has 16 markings on the bell resembling elongated v's, surrounding a central brown spot. Its mouth is located at the bottom center of the bell, between 4 larger tentacles. They are known to sting.