Cassiopea ndrosia | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Cnidaria |
Class: | Scyphozoa |
Order: | Rhizostomeae |
Family: | Cassiopeidae |
Genus: | Cassiopea |
Species: | C. ndrosia |
Binomial name | |
Cassiopea ndrosia Agassiz & Mayer, 1899 [1] | |
Cassiopea ndrosia is a species of true jellyfish in the family Cassiopeidae. It has been found in the Pacific Ocean and in waters surrounding Australia and Fiji. [2] [3] [4]
The genus name derives from Cassiopeia, a figure in Greek mythology. The specific epithet, ndrosia, was derived from the native Fijian name for the species, ndrosi. [1]
Cassiopea ndrosia has eight oral arms, around 30 mm (1.2 in) in length, that have suction-mouths and leaf-shaped vesicles on their lower surface. The upper portions of these arms can range from white to slightly gray; the suction-mouths are surrounded by small tentacles that are a deep brown color, and the vesicles are an olive-green. It has four sub-genital cavities, and four gonads. Its bell is disk-shaped and flat, and is around 50 mm (1.9 in) in diameter. The number of rhopalia can vary, with the original description noting there were instances of specimens having 18 and 22. The rhopalia are equidistant from each other. It has two sets of muscle bands; a number of these, in the lower bell, radiate towards the rhopalia. These bands are opaque and white, while those on the top of the bell are a deep blue-green color. The bell is mostly an ashy brown, otherwise. Each rhopalium has a white spot on its radius, and there are often four white streaks between each adjacent pair of rhopalia. Additionally, there are several white spots on the inner area of the lower bell. It has four small pores, or ostia, in the sub-genital area. [1]
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-shaped bells and trailing tentacles, although a few are anchored to the seabed by stalks rather than being mobile. The bell can pulsate to provide propulsion for highly efficient locomotion. The tentacles are armed with stinging cells and may be used to capture prey and defend against predators. Jellyfish have a complex life cycle; the medusa is normally the sexual phase, which produces planula larvae that disperse widely and enter a sedentary polyp phase before reaching sexual maturity.
The Scyphozoa are an exclusively marine class of the phylum Cnidaria, referred to as the true jellyfish.
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work mainly like muscular hydrostats. Most forms of tentacles are used for grasping and feeding. Many are sensory organs, variously receptive to touch, vision, or to the smell or taste of particular foods or threats. Examples of such tentacles are the eyestalks of various kinds of snails. Some kinds of tentacles have both sensory and manipulatory functions.
Rhopalia are small sensory structures of certain Scyphozoan and Cubozoan species.
Rhizostomae or 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.
Cassiopea is a genus of true jellyfish and the only members of the family Cassiopeidae. They are found in warmer coastal regions around the world, including shallow mangrove swamps, mudflats, canals, and turtle grass flats in Florida, and the Caribbean and Micronesia. The medusa usually lives upside-down on the bottom, which has earned them the common name. These jellyfish partake in a symbiotic relationship with photosynthetic dinoflagellates and therefore, must lie upside-down in areas with sufficient light penetration to fuel their energy source. Where found, there may be numerous individuals with varying shades of white, blue, green and brown.
Discomedusae is a subclass of jellyfish in the class Scyphozoa. It is the sister taxon of Coronamedusae. Discomedusae contains about 155 named species and there are likely to be many more as yet undescribed. Jellyfish in this subclass are much more likely to have swarming events or form blooms than those in Coronamedusae. Discomedusae consists of two orders, Rhizostomae and Semaeostomeae.
The quagga catshark is a species of catshark, belonging to the family Scyliorhinidae. A small, slim-bodied shark reaching 37 cm (15 in) in length, it has a distinctive color pattern of narrow, dark brown vertical bars, which resemble those of the quagga. Its head is short and flattened, with a pointed snout tip that is not upturned.
The Pacific sea nettle, or West Coast sea nettle, is a common planktonic scyphozoan that lives in the eastern Pacific Ocean from Canada to Mexico.
Clytia gregaria, sometimes referred to as the gregarious jellyfish, is a small species of hydrozoan in the family Campanulariidae. It is one of the most abundant hydrozoans of the Pacific Northwest, particularly during late spring and summer.
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.
Dendraster excentricus, also known as the eccentric sand dollar, sea-cake, biscuit-urchin, western sand dollar, or Pacific sand dollar, is a species of sand dollar in the family Dendrasteridae. It is a flattened, burrowing sea urchin found in the north-eastern Pacific Ocean from Alaska to Baja California.
Stygiomedusa gigantea, commonly known as the giant phantom jelly, is the only species in the monotypic genus of deep sea jellyfish, Stygiomedusa. It is in the Ulmaridae family. With only around 110 sightings in 110 years, it is a jellyfish that is rarely seen, but believed to be widespread throughout the world, with the exception of the Arctic Ocean.
Luidia ciliaris, the seven-armed sea star, is a species of sea star (starfish) in the family Luidiidae. It is found in the eastern Atlantic Ocean and the Mediterranean Sea.
Bathykorus bouilloni is a species of hydrozoan first described in 2010. It is a deep-sea species found in the Arctic Ocean, and appears to be common at depths below 1,000 m (3,300 ft). It is the only species in the monotypic genus Bathykorus. The genus name comes from the Greek bathy meaning "deep" and korus meaning "helmet", referring to the depth at which this species is found and to the shape of the bell. Its helmet-like appearance bears a resemblance to the helmet of Darth Vader, giving it the nickname Darth Vader jellyfish. The specific name is in honour of Dr. Jean Bouillon, (1926–2009), a marine zoologist.
Tripedalia cystophora is a small species of box jellyfish in the family Tripedaliidae. It is native to the Caribbean Sea and the Central Indo-Pacific.
Cassiopea xamachana, commonly known as the upside-down jellyfish, is a species of jellyfish in the family Cassiopeidae. It is found in warm parts of the western Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico. It was first described by the American marine biologist Henry Bryant Bigelow in 1892.
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.
Mastigias siderea is a species of jellyfish in the family Mastigiidae. It is native to the southern Pacific Ocean.
Netrostoma dumokuroa is a species of true jellyfish in the family Cepheidae. It has been found in the South Pacific Ocean surrounding Fiji.