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Medusozoans
Medusozoa is a clade in the phylum Cnidaria, and is often considered a subphylum. It includes the classes Hydrozoa, Scyphozoa, Staurozoa and Cubozoa, and possibly the parasitic Polypodiozoa. Medusozoans are distinguished by having a medusa stage in their often complex life cycle, a medusa typically being an umbrella-shaped body with stinging tentacles around the edge. With the exception of some Hydrozoa (and Polypodiozoa), all are called jellyfish in their free-swimming medusa phase. Evolution The phylum Cnidaria is widely accepted as being monophyletic and consisting of two clades, Anthozoa and Medusozoa. Anthozoa includes the classes Hexacorallia, the hard corals, and Octocorallia, the soft corals, as well as Ceriantharia, the tube-dwelling anemones. There is strong support for this group having been the first to branch off from the ancestral line. Medusozoa includes the classes Staurozoa, Cubozoa, Scyphozoa and Hydrozoa, but the relationships between these are unclear. An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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-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 animal locomotion, locomotion. The tentacles are armed with Cnidocyte, stinging cells and may be used to capture prey and defend against predators. Jellyfish have a complex Biological life cycle, life cycle; the medusa is normally the sexual phase, which produces planula larvae that disperse widely and enter a sedentary polyp (zoology), polyp phase before reaching sexual maturity. Jellyfish are found all over the world, from surface waters to the deep sea. Scyphozoans (the "true jellyfish") are exclusively marine habitats, marine, but some hydrozoans with a simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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-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 animal locomotion, locomotion. The tentacles are armed with Cnidocyte, stinging cells and may be used to capture prey and defend against predators. Jellyfish have a complex Biological life cycle, life cycle; the medusa is normally the sexual phase, which produces planula larvae that disperse widely and enter a sedentary polyp (zoology), polyp phase before reaching sexual maturity. Jellyfish are found all over the world, from surface waters to the deep sea. Scyphozoans (the "true jellyfish") are exclusively marine habitats, marine, but some hydrozoans with a simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysaora Fuscescens
The Pacific sea nettle (''Chrysaora fuscescens''), or West Coast sea nettle, is a common Plankton, planktonic scyphozoan that lives in the eastern Pacific Ocean from Canada to Mexico. Sea nettles have a distinctive golden-brown bell with a reddish tint. The bell can grow to be larger than one meter (three feet) in diameter in the wild, though most are less than 50 cm across. The long, spiraling, white oral arms and the 24 undulating maroon tentacles may trail behind as far as 15 feet (4.6 m). For humans, its sting is often irritating, but rarely dangerous. ''Chrysaora fuscescens'' has proven to be very popular for display at public aquariums due to their bright colors and relatively easy maintenance. It is possible to establish polyps and culture ''Chrysaora'' in captivity. When provided appropriate aquarium conditions, the medusae do well under captive conditions. Taxonomy Johann Friedrich von Brandt described this species in 1835. The origin of the genus name ''Chrysaora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tube-dwelling Anemone
Tube-dwelling anemones or ceriantharians look very similar to sea anemones but belong to an entirely different class of anthozoans. They are solitary, living buried in soft sediments. Tube anemones live inside and can withdraw into tubes, which are composed of a fibrous material made from secreted mucus and threads of nematocyst-like organelles known as ptychocysts. Within the tubes of these ceriantharians, more than one polyp is present, which is an exceptional trait because species that create tube systems usually contain only one polyp per tube. Ceriantharians were formerly classified in the taxon Ceriantipatharia along with the black corals but have since been moved to their own subclass, Ceriantharia. Ceriantharians have a crown of tentacles that are composed of two whorls of distinctly different sized tentacles. The outer whorl consists of large tentacles that extend outwards. These tentacles taper to points and are mostly used in food capture and defence. The smaller inn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haliclystus Stejnegeri 1
''Haliclystus'' is a genus of stalked jellyfish that contains 11 species and one nomen nudum (''Haliclystus sanjuanensis''). It is the largest genus in the order Stauromedusae. Members of this genus are found in the Pacific, Atlantic, Indian, Arctic, and Southern oceans. Two members of this genus, '' Haliclystus kerguelensis'' and ''Haliclystus antarcticus'', are found in the Southern hemisphere only. The remaining 9 members are found in the Northern hemisphere only.http://www.mapress.com/zootaxa/2010/f/zt02518p059.pdf Species in this genus have four longitudinal planes of symmetry. They have eight arms which are tipped with clusters of secondary tentacles. The number of these secondary tentacles is reported to vary across the different species. Species in this genus also have eight large pads known as anchors located between the arms. These vary in size and shape and currently play in important role in differentiating one species from another. Some, but not all, species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estonian Museum Of Natural History - Conularia
Estonian may refer to: * Something of, from, or related to Estonia, a country in the Baltic region in northern Europe * Estonians, people from Estonia, or of Estonian descent * Estonian language * Estonian cuisine * Estonian culture See also * * Estonia (other) * Languages of Estonia * List of Estonians This is a list of notable Estonians. Architects * Andres Alver (born 1953) *Dmitri Bruns (1929–2020) * Karl Burman (1882–1965) * Eugen Habermann (1884–1944) *Georg Hellat (1870–1943) *Otto Pius Hippius (1826–1883) * Erich Jacoby (1885†... {{Disambiguation Language and nationality disambiguation pages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinostola 3
''Actinostola'' is a genus of sea anemones in the order Actiniaria. All members of this genus are deep-sea species, with some occurring at hydrothermal vents. Species The following species are recognised by the World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive list of names of marine organisms. Content The content of the registry is edited and maintained by scientific specialist ...: *'' Actinostola abyssorum'' (Danielssen, 1890) *'' Actinostola bulbosa'' (Carlgren, 1928) *'' Actinostola callosa'' (Verrill, 1882) *'' Actinostola capensis'' (Carlgren, 1928) *'' Actinostola carlgreni'' Wassilieff, 1908 *'' Actinostola chilensis'' McMurrich, 1904 *'' Actinostola crassicornis'' (Hertwig, 1882) *'' Actinostola faeculenta'' (McMurrich, 1893) *'' Actinostola georgiana'' Carlgren, 1927 *'' Actinostola groenlandica'' Carlgren, 1899 *'' Actinostola kerguelensis'' Carlgren, 1928 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comb Jelly
Ctenophora (; ctenophore ; ) comprise a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), and they are the largest animals to swim with the help of cilia. Depending on the species, adult ctenophores range from a few millimeters to in size. Only 100 to 150 species have been validated, and possibly another 25 have not been fully described and named. The textbook examples are cydippids with egg-shaped bodies and a pair of retractable tentacles fringed with tentilla ("little tentacles") that are covered with colloblasts, sticky cells that capture prey. Their bodies consist of a mass of jelly, with a layer two cells thick on the outside, and another lining the internal cavity. The phylum has a wide range of body forms, including the egg-shaped cydippids with retractable tentacles that capture prey, the flat generally combless pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenophora
Ctenophora (; ctenophore ; ) comprise a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), and they are the largest animals to swim with the help of cilia. Depending on the species, adult ctenophores range from a few millimeters to in size. Only 100 to 150 species have been validated, and possibly another 25 have not been fully described and named. The textbook examples are cydippids with egg-shaped bodies and a pair of retractable tentacles fringed with tentilla ("little tentacles") that are covered with colloblasts, sticky cells that capture prey. Their bodies consist of a mass of jelly, with a layer two cells thick on the outside, and another lining the internal cavity. The phylum has a wide range of body forms, including the egg-shaped cydippids with retractable tentacles that capture prey, the flat generally combless plat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animalia
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptothecata
Leptothecata, or thecate hydroids, are an order of hydrozoans in the phylum Cnidaria. Their closest living relatives are the athecate hydroids, which are similar enough to have always been considered closely related, and the very apomorphic Siphonophorae, which were placed outside the "Hydroida". Given that there are no firm rules for synonymy for high-ranked taxa, alternative names like Leptomedusa, Thecaphora or Thecata, with or without the ending emended to "-ae", are also often used for Leptothecata. Leptothecata is surrounded by a chitinous outer layer as its exoskeleton, including gonophores, their reproductive organ. Leptothecata obtain radial symmetry, in which their gonads can be found in their radial canals. Their morphological characters normally have ranged from benthic to planktonic stages. Characters associated with benthic are the polyps and colony forms, while planktonic is medusae. Leptothecata has a vast and complex variation among all species within the hydrozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
28S RDNA
28S ribosomal RNA is the structural ribosomal RNA (rRNA) for the LSU rRNA, large subunit (LSU) of eukaryotic cytoplasmic ribosomes, and thus one of the basic components of all eukaryotic cells. It has a size of 25S in plants and 28S in mammals, hence the alias of 25S–28S rRNA. Combined with 5.8S rRNA to the 5' side, it is the eukaryotic nuclear homologue of the 23S, prokaryotic 23S and MT-RNR2, mitochondrial 16S ribosomal RNAs. Use in phylogeny The genes coding for 28S rRNA are referred to as 28S rDNA. The comparison of the Nucleic acid sequence, sequences from these genes are sometimes used in molecular analysis to construct phylogenetic trees, for example in protists, Fungus, fungi, insects, arachnids, tardigrades, and vertebrates. Structure The 28S rRNA is typically 4000–5000 nt long. Some eukaryotes cleave 28S rRNA into two parts before assembling both into the ribosome, a phenomenon termed the "hidden break". Databases Several databases provide Sequence al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
