''Cephea cephea'', also known as the crown jellyfish, or cauliflower jellyfish, is a species of

jellyfish Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella- ...

in the family Cepheidae. It occurs in the tropical waters of the western Indo-Pacific to Northern Australia. The species was first described by

Peter Forsskål Peter Forsskål, sometimes spelled Pehr Forsskål, Peter Forskaol, Petrus Forskål or Pehr Forsskåhl (11 January 1732 – 11 July 1763) was a Swedish-speaking Finnish explorer, orientalist, naturalist, and an apostle of Carl Linnaeus. Early ...

in 1775 and originally given the name ''Medusa cephea''. It inhabits the

pelagic zone The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or w ...

of tropical and sub-tropical waters and is most commonly found in the Indo-West Pacific, eastern Atlantic and the Red Sea. Although this species is among the most

venomous Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a ...

jellyfish, it is not harmful to humans and is eaten as a delicacy and used for medical purposes in China and Japan. The species can achieve a diameter of up to 60 cm.

Description

''Cephea cephea'' is purplish-blue in color and grow to up to 60 centimeters in diameter. This species has wart-like projections and a bell shape that is associated with the given common names for the species. As in other jellyfish species, the tentacles contain nematocysts that are used to stun, kill and grapple prey items. Its lifespan is approximately three to six months.

Ecology

This species of jellyfish is known to live in the Pelagic zone of the ocean in the Indo-West Pacific, Eastern Atlantic and the Red Sea. They live and thrive in cold water and can be found as deep as over 3,000 feet below the surface. The species is

bioluminescent Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some b ...

. During the day it tends to remain in deeper waters, migrating to surface waters at night. Its prey mainly consists of algae, shrimp, plankton, invertebrate eggs and invertebrate larvae. The most common known predators of the species are sea turtles.

Reproduction

The reproduction cycle is similar to many other jellyfish. Adults release sperm or egg into the water; fertilized eggs form

planula A planula is the free-swimming, flattened, ciliated, bilaterally symmetric larval form of various cnidarian species and also in some species of Ctenophores. Some groups of Nemerteans also produce larvae that are very similar to the planula, whi ...

larvae. The planula then attaches itself to a rock or similar structure that allows it to grow into a polyp. Asexual reproduction then occurs meaning the polyp essentially clones itself and develop into another stage called the ephyra. The last process is the growth and development into an adult medusa jellyfish. Water temperature and food supply influence the efficiency of the asexual reproduction phase.

Venom and human use

''Cephea cephea'' is known to be one of the most venomous jellyfish. Although they have large amounts of venom deadly to their prey, their stings and venom is not harmful to humans. They are actually known to be eaten by humans located mostly in Japan and China. The dish is a delicacy in the Japanese and Chinese cultures. This particular species of jellyfish is used also used for medicinal purposes for humans.

Gallery

Cephea cephea.webm Cauliflour Jellyfish, Cephea cephea at Marsa Shouna, Red Sea - 3.jpg Cauliflour Jellyfish, Cephea cephea at Marsa Shouna, Red Sea.jpg Cephea cephea jellyfish.jpg The water is full of Cauliflour Jellyfish, Cephea cephea at Marsa Shouna, Red Sea, Egypt -SCUBA (6238367346).jpg Cephea cephea Landaa.JPG

References

{{Taxonbar, from=Q3380378 Cepheidae Animals described in 1775