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.
Apolemia uvaria
String jellyfish are colonial animals that may reach 3 m in total length and have a diameter of 2–5 cm. The colony is formed of a central string, bearing groups of pink and white tentacles, which clump together or extend. The whole colony has a gas float at the front and a set of swimming bells. This colonial animal is pelagic and is found in oceans worldwide in midwater. These ocean predators act like drift nets, spreading their tentacles to catch plankton. The tentacles give a painful sting and are best avoided.