Cnidaria is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, including jellyfish, hydroids, sea anemone, corals and some of the smallest marine parasites. Their distinguishing features are a decentralized nervous system distributed throughout a gelatinous body and the presence of cnidocytes or cnidoblasts, specialized cells with ejectable flagella used mainly for envenomation and capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick.
Jellyfish and sea jellies are the common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, which is a major part of the phylum Cnidaria.
The Scyphozoa are an exclusively marine class of the phylum Cnidaria, referred to as the true jellyfish.
Aurelia aurita is a species of the family Ulmaridae. All species in the genus are very similar, and it is difficult to identify Aurelia medusae without genetic sampling; most of what follows applies equally to all species of the genus.
Rhizostomeae is an order of jellyfish. Species of this order have neither tentacles nor other structures at the bell's edges. Instead, they have eight highly branched oral arms, along which there are suctorial minimouth orifices. These oral arms become fused as they approach the central part of the jellyfish. The mouth of the animal is also subdivided into minute pores that are linked to coelenteron.
Jellyfish Lake is a marine lake located on Eil Malk island in Palau. Eil Malk is part of the Rock Islands, a group of small, rocky, mostly uninhabited islands in Palau's Southern Lagoon, between Koror and Peleliu. There are about 70 other marine lakes located throughout the Rock Islands. Millions of golden jellyfish migrate horizontally across the lake daily.
Phacellophora camtschatica, commonly known as the fried egg jellyfish or egg-yolk jellyfish, is a very large jellyfish in the family Phacellophoridae. This species can be easily identified by the yellow coloration in the center of its body which closely resembles an egg yolk, hence how it got its common name. Some individuals can have a bell close to 60 cm (2 ft) in diameter, and most individuals have 16 clusters of up to a few dozen tentacles, each up to 6 m (20 ft) long. A smaller jellyfish, Cotylorhiza tuberculata, typically found in warmer water, particularly in the Mediterranean Sea, is also popularly called a fried egg jellyfish. Also, P. camtschatica is sometimes confused with the Lion's mane jellyfish.
Phyllorhiza punctata is a species of jellyfish, also known as the floating bell, Australian spotted jellyfish, brown jellyfish or the white-spotted jellyfish. It is native to the western Pacific from Australia to Japan, but has been introduced widely elsewhere. It feeds primarily on zooplankton. P. punctata generally can reach up to 50 centimetres (20 in) in bell diameter, but in October 2007, one 72 cm (28 in) wide, perhaps the largest ever recorded, was found on Sunset Beach, North Carolina.
Cotylorhiza is a genus of true jellyfish from the family Cepheidae. The genus is found in the central-east Atlantic, Mediterranean, and western Indian Ocean.
The spotted jelly, lagoon jelly, golden medusa, or Papuan jellyfish, is a species of jellyfish from the Indo-Pacific oceans. Like corals, sea anemones, and other sea jellies, it belongs to the phylum Cnidaria. Mastigias papua is one of the numerous marine animals living in symbiosis with zooxanthellae, a photosynthetic alga.
Mastigias is a genus of true jellyfish in the family Mastigiidae. It contains seven described species. Members of this genus are found widely in coastal regions of the Indo-Pacific, including saline lakes of Palau, but there are also records from the West Atlantic at Florida and Puerto Rico. The West Atlantic records are most likely the result of accidental introductions by humans.
Chrysaora hysoscella, the compass jellyfish, is a common species of jellyfish that inhabits coastal waters in temperate regions of the northeastern Atlantic Ocean, including the North Sea and Mediterranean Sea. In the past it was also recorded in the southeastern Atlantic, including South Africa, but this was caused by confusion with close relatives; C. africana, C. fulgida and an undescribed species tentatively referred to as "C. agulhensis".
Cassiopea andromeda is one of many cnidarian species called the upside-down jellyfish. It usually lives in intertidal sand or mudflats, shallow lagoons, and around mangroves. This jellyfish, often mistaken for a sea anemone, usually keeps its mouth facing upward. Its yellow-brown bell, which has white or pale streaks and spots, pulsates to run water through its arms for respiration and to gather food.
Clear Lake is a marine lake located on Eil Malk island in Palau. Eil Malk is part of the Rock Islands, a group of small, rocky, mostly uninhabited islands in Palau's Southern Lagoon, between Koror and Peleliu. There are about 70 other marine lakes located throughout the Rock Islands. Clear Lake is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology, the other lakes being Jellyfish Lake, Goby Lake, Uet era Ngermeuangel, Uet era Ongael.
Goby Lake is a marine lake located on Koror island in Palau. There are about 70 other marine lakes located throughout the Rock Islands and Koror. Goby Lake is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology the other lakes being Jellyfish Lake, Clear Lake (Palau), Uet era Ngermeuangel, Uet era Ongael.
Uet era Ngermeuangel is a marine lake located on Koror island in Palau. There are about 70 other marine lakes located throughout the Rock Islands and Koror. Uet era Ngermeuangel is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology the other lakes being Jellyfish Lake, Clear Lake (Palau), Goby Lake, Uet era Ongael.
Uet era Ongael is a marine lake located on Ongael Island, Koror, in Palau. There are about 70 other marine lakes located throughout the Rock Islands and Koror. Uet era Ongael is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology, the other lakes being Jellyfish Lake, Clear Lake, Uet era Ngermeuangel and Goby Lake.
Rhopilema verrilli, or mushroom cap jellyfish, is a species of jellyfish in the family Rhizostomatidae. They are cnidarian invertebrates distinguished by their mushroom-shaped medusae. The species does not have any tentacles; however, they still have stinging cells, called nematocysts, within their bells, which can produce mild stings to humans.
Cassiopea ornata are one of many Cnidarian species called the upside-down jellyfish. This pelagic jellyfish primarily lives in tropical waters, off the coast of Australia in shallow lagoons and around mangrove trees. The name "upside-down jellyfish" comes from the fact that it appears to be upside-down in its natural state—resting on its bell. Its bell is a golden/brown color and the tentacles vary with different shades of yellow. While the sighting of this particular species is rare, it is usually mistaken for vegetation like the other species in genus Cassiopea.
Desmonema is a genus of jellyfish under the Cyaneidae family found in colder waters near the Antarctic region and off of the coast of Argentina. They have a bell diameter that can extend over 1 meter and wide tentacles that are grouped together in clusters. They share similar anatomical and physiological structures to the genus Cyanea. Their sophisticated structures like the thick tentacles, sensory systems, and gastrovascular system allow Desmonema to easily capture and extracellularly digest their prey. In recent years, Desmonema were reported to have a commensal relationship with fishes under the Trachurus genus and a parasitic relationship with specimens of the Hyperia genus. The genus name derives from the Ancient Greek desmós (δεσμός), meaning "bond", and nêma (νῆμᾰ), meaning "thread".
