Jellyfish

‘ Join us as we travel the oceans far and wide with these electric jellyfish facts! Fast jellyfish facts Phylum: Cnidaria Class: Scyphozoa Classification: Invertebrate IUCN status: Not evaluated Lifespan (in wild): One year Weight: Up to 2kg Body size: 2cm to 2m Top speed: 8km/h Diet: Fish, shrimp, crabs, tiny plants and even other species of jellyfish Habitat: Oceans Range: Jellyfish have been around for millions of years, even before dinosaurs lived on the Earth. Pulsing along on our ocean currents, these jelly-like creatures can be found in waters both cold and warm, deep and shallow and along coastlines, too. Some jellyfish are clear, but others are vibrant colours of pink, yellow, blue and purple. They can be bioluminescent, too, which means they produce their own light! Jellyfish have no brain, heart, bones or eyes. They aremade up of a smooth, bag-like body and tentacles armed with tiny, stinging cells. These incredible invertebrates use their stinging tentacles tostun or paralyseprey before gobbling it up. The jellyfish’s mouth is found in the centre of its body. From this small opening it both eats and discards waste. And it serves another purpose, too – by squirting a jet of water from its mouth, the jellyfish can propel forward! Cool, eh? Jellyfish digest their food, which consists of fish, shrimp, crabs and tiny plants, very quickly. If they didn’t, they wouldn’tbe able to float, being weighed down by the large, undigested grub in their body. The jellyfish itse...

Before we dive in, let’s take a quick overview of these fantastic animals starting with considering how many species of jellyfish there are. There are about 1,800 species inside the classes of medusozoan Cnidaria that marine scientists regard as jellyfish. Jellyfish are the common names given to an extensive range of animals in the subphylum Medusozoa, part of the phylum Cnidaria, which includes four major classes. Sometimes you’ll see this question answered with only the class Scyphozoa, which are occasionally called true jellies. However, this is only part of the picture. Reading Suggestion: How to identify The In addition to Scyphozoa (true jellyfish – about 200 species), there are also Cubozoa (box jellyfish – about 50 species), Staurozoa (stalked jellyfish – about 50 species), and Hydrozoa medusae (tiny, predatory animals – about 1,500 species). You can find jellyfish everywhere in the world’s oceans, from the surface of tropical waters to the deepest depths, including in the Hydrozoans are so small that you’re unlikely to come across them, so we will concentrate on the types of jellyfish you’re more likely to see. Moon jellyfish are a very common scyphozoan jellyfish species about 25–40 cm (10–16 in) in diameter, which is seen at or near the surface in coastal waters. You can find moon jellies in almost any ocean, except the Arctic, as they will tolerate a wide range of temperatures between 6 – 31°C (43 – 88°F). Moon jellyfish often have a distinctive purple color. T...

Study a jellyfish's muscular contractions and learn how the carnivore uses its tentacles to catch prey Free-swimming scyphozoan jellyfish occur in all oceans and include the familiar disk-shaped animals that are often found drifting along the shoreline. Most live for only a few weeks, but some are known to survive a year or longer. The bodies of most range in size from about 2 to 40 cm (1 to 16 inches) in diameter; some species are considerably larger, however, with diameters of up to 2 metres (6.6 feet). Scyphozoan medusae consist of almost 99 percent water as a result of the Animals Down Under The life cycle of free-swimming scyphozoan jellyfish typically consists of three stages. A sessile Aurelia and Chrysaora and the big red jellyfish, Tiburonia granrojo (subfamily Tiburoniinae), one of only three species of jellyfish that lack tentacles. The order Conulata, which flourished between about 180 and 600 million years ago. Some of the known sessile stages form branched colonies, which were once separately identified under the name Stephanoscyphus. Cassiopea viewed from above. The order Cassiopea, the upside-down jellyfish, however, swim infrequently and sit inverted in tropical shallows, exposing their photosynthetic symbiotic algae to sunlight. The group Rhizostomeae is found mainly in shallow tropical to subtropical seas in the Indo-Pacific region, but members of the genus Rhizostoma, also called football jellyfish, often inhabit cooler waters, and Cotylorhiza is common...

Overview Jellyfish stings are fairly common problems for people swimming, wading or diving in oceans. The long tentacles trailing from the jellyfish can inject venom from thousands of microscopic barbed stingers. Most often jellyfish stings cause instant pain and inflamed marks on the skin. Some stings may cause more whole-body (systemic) illness. And in rare cases they're life-threatening. Symptoms Symptoms of jellyfish stings include: • Burning, prickling, stinging pain • Welts or tracks on the skin — a "print" of the tentacles' contact with the skin • Itchiness (pruritus) • Swelling • Throbbing pain that radiates up a leg or an arm Severe jellyfish stings can affect multiple body systems. These reactions may appear rapidly or several hours after the stings. Symptoms of severe jellyfish stings include: • Stomach pain, nausea and vomiting • Headache • Muscle pain or spasms • Faintness, dizziness or confusion • Difficulty breathing • Heart problems The severity of a reaction depends on: • The type and size of the jellyfish • The age, size and health of the person affected, with severe reactions more likely in children • How long the person was exposed to the stingers • How much of the skin is affected When to see a doctor Seek emergency treatment if you have severe symptoms. See your health care provider if your symptoms worsen or the wound shows symptoms of infection. Causes Jellyfish stings are caused by brushing against a jellyfish tentacle. Tentacles have thousands of ...