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Medusoids
Jellyfish, also known as sea jellies or simply jellies, are the medusa-phase of certain gelatinous members of the subphylum Medusozoa, which is a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals, although a few are anchored to the seabed by stalks rather than being motile. They are made of an umbrella-shaped main body made of mesoglea, known as the ''bell'', and a collection of trailing tentacles on the underside. Via pulsating contractions, the bell can provide propulsion for locomotion through open water. The tentacles are armed with stinging cells and may be used to capture prey or to defend against predators. Jellyfish have a complex life cycle, and the medusa is normally the sexual phase, which produces planula larvae. These then disperse widely and enter a sedentary polyp phase which may include asexual budding before reaching sexual maturity. Jellyfish are found all over the world, from surface waters to the deep sea. Scyphozoan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysaora Fuscescens
''Chrysaora fuscescens'', the Pacific sea nettle or West Coast sea nettle, is a widespread planktonic scyphozoan cnidarian—or ''medusa'', "jellyfish" or "jelly"—that lives in the northeastern Pacific Ocean, in temperate to cooler waters off of British Columbia and the West Coast of the United States, ranging south to Mexico. The Pacific sea nettle earned its common name in-reference to its defensive, 'Urtica, nettle'-like sting; much like the Urtica dioica, stinging nettle plant (''Urtica dioica''), the sea nettle's defensive sting is often irritating (possibly mildly painful) to humans, though rarely dangerous. The Pacific sea nettle has a distinctive, golden-brown ''bell''—the main functioning 'body' or 'head' of a jelly—with a reddish tint. The bell can grow to be larger than one meter (3’) in diameter in the wild; however, most are less than 50 cm across. The long and spiraling, whitish oral arms (and 24 undulating, maroon tentacles) may trail behind the nettle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
