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Staurozoa
Staurozoa is a class of Medusozoa, jellyfishes and hydrozoans. It has one extant order: Stauromedusae (stalked jellyfishes) with a total of 50 known species. A fossil group called Conulariida has been proposed as a second order, although this is highly speculative. The extinct order is largely unknown and described as a possibly cnidaria Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in Fresh water, freshwater and Marine habitats, marine environments, predominantly the latter. Their distinguishing feature is cnidocyt ...n clade of marine life with shell-like structures, the Conulariida. Staurozoans are small animals () that live in marine environments, usually attached to seaweeds, rocks, or gravel.Collins, A. G. (n.d.). Staurozoa. ''AccessScience''. doi:10.1036/1097-8542.652700 They have a large antitropical distribution, a majority found in boreal or polar, near-shore, and shallow waters. Few staurozoans are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnidaria
Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in Fresh water, freshwater and Marine habitats, marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell (biology), cell thick. Cnidarians mostly have two basic body forms: swimming Medusa (biology), medusae and Sessility (motility), sessile polyp (zoology), polyps, both of which are Symmetry (biology)#Radial symmetry, radially symmetrical with mouths surrounded by tentacles that bear cnidocytes. Both forms have a single Body orifice, orifice and body cavity that are used for digestion and respiration (physiology), respiration. Many cnidarian species produce Colony (biology), colonies that are single organisms composed of medusa-like or polyp (z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staurozoa
Staurozoa is a class of Medusozoa, jellyfishes and hydrozoans. It has one extant order: Stauromedusae (stalked jellyfishes) with a total of 50 known species. A fossil group called Conulariida has been proposed as a second order, although this is highly speculative. The extinct order is largely unknown and described as a possibly cnidaria Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in Fresh water, freshwater and Marine habitats, marine environments, predominantly the latter. Their distinguishing feature is cnidocyt ...n clade of marine life with shell-like structures, the Conulariida. Staurozoans are small animals () that live in marine environments, usually attached to seaweeds, rocks, or gravel.Collins, A. G. (n.d.). Staurozoa. ''AccessScience''. doi:10.1036/1097-8542.652700 They have a large antitropical distribution, a majority found in boreal or polar, near-shore, and shallow waters. Few staurozoans are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medusozoa
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] |
Stauromedusae
Stauromedusae are the stalked jellyfishes. They are the sole living members of the class Staurozoa and belong to the medusozoa subphylum of Cnidaria. They are unique among medusa jellyfish in that they do not have an alternation of polyp and medusa life cycle phases, but are instead interpreted as an attached medusa stage. With a lifestyle more resembling that of polypoid forms. They have a generally trumpet-shaped body, oriented upside-down in comparison with other jellyfish, with the tentacles projecting upwards, and the stalk located in the centre of the umbrella. Members of this class are commonly found in relatively cold waters, close to the shoreline. Sexually mature stauromedusae free-spawn eggs or sperm, which fertilize in the sea and form a creeping, unciliated planula larva. The larvae crawl across the sea floor and find a suitable place, attaching themselves typically to rock or algae, where they eventually develop into a new, attached stauromedusa. Unlike most scypho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haliclystus Sanjuanensis
''Haliclystus sanjuanensis'' is a species of small (~4 cm) stalked jellyfish found in the Pacific Ocean along the west coast of North America. This species can be found in shallow waters at low tide on soft substrates such as seagrass (''Phyllospadix ''Phyllospadix'', surfgrass, is a genus of seagrass, a flowering plant in the family Zosteraceae, described as a genus in 1840. ''Phyllospadix'' grows in marine waters along the coasts of the temperate North Pacific. It is one of the seag ...''). A variety of colour morphs can be found ranging from yellow-green to red. ''Haliclystus sanjuanensis'' remains undescribed officially, despite sequence data establishing it as a distinct taxon. Gallery Colour morphs of ''Haliclystus sanjuanensis'': File: Green subum.jpg , Green File: Grorange subum.jpg , Green-orange File: Orange exum 3.jpg , Orange File: Red exum.jpg , Red File: Inverted Hali stretched mesoglea maybe - buckling of flesh 2.tif , Juvenile ''H. sanjuanensis'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manania Handi
''Manania handi'' is a species of stalked jellyfish found in the Pacific Ocean along the west coast of North America. This species can be found in shallow waters at low tide on soft substrates such as seagrass (''Phyllospadix''), but the related '' M. gwilliami'' have also been recovered at depths of >10 metres. This may reflect that intertidal specimens represent the fringes of a population that is typically more commonly found in the subtidal zone. ''Manania handi'' reaches a length of up to 4 cm, but the diameter of the bell at the oral end is relatively narrow at approximately 2 cm in fully-grown specimens. Distinctive pigment bands along the calyx and the relatively short stalk (or peduncle) distinguish it from related '' Manania'' species. ''Manania handi'' is also described typically as green with cream coloured gonads and vivid white nematocyst vesicles. However the colour patterns of M. handi can vary from brownish-yellow to vivid green. The name "''handi''" ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conulatae
Conulariida is a poorly understood fossil group that has possible affinity with the Cnidaria. Their exact position as a taxon of extinct medusozoan cnidarians is highly speculative. Members of the Conulariida are commonly referred to as conulariids and appear in the fossil record from the latest parts of the Ediacaran period up until the Triassic. Structure The conulariids are fossils preserved as shell-like structures made up of rows of calcium phosphate rods, resembling an ice-cream cone with fourfold symmetry, usually four prominently-grooved corners. New rods were added as the organism grew in length; the rod-based growth falsely gives the fossils a segmented appearance. Exceptional soft-part preservation has revealed that soft tentacles protruded from the wider end of the cone, and a holdfast from the pointed end attached the organisms to hard substrate. The prevailing reconstruction of the organism has it look superficially like a sea anemone sitting inside an angular, ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conulariida
Conulariida is a poorly understood fossil group that has possible affinity with the Cnidaria. Their exact position as a taxon of extinct medusozoan cnidarians is highly speculative. Members of the Conulariida are commonly referred to as conulariids and appear in the fossil record from the latest parts of the Ediacaran period up until the Triassic. Structure The conulariids are fossils preserved as shell-like structures made up of rows of calcium phosphate rods, resembling an ice-cream cone with fourfold symmetry, usually four prominently-grooved corners. New rods were added as the organism grew in length; the rod-based growth falsely gives the fossils a segmented appearance. Exceptional soft-part preservation has revealed that soft tentacles protruded from the wider end of the cone, and a holdfast from the pointed end attached the organisms to hard substrate. The prevailing reconstruction of the organism has it look superficially like a sea anemone sitting inside an angular, ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haliclystus Antarcticus
''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, specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Class (biology)
In biological classification, class ( la, classis) is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank. It is a group of related taxonomic orders. Other well-known ranks in descending order of size are life, domain, kingdom, phylum, order, family, genus, and species, with class fitting between phylum and order. History The class as a distinct rank of biological classification having its own distinctive name (and not just called a ''top-level genus'' ''(genus summum)'') was first introduced by the French botanist Joseph Pitton de Tournefort in his classification of plants that appeared in his ''Eléments de botanique'', 1694. Insofar as a general definition of a class is available, it has historically been conceived as embracing taxa that combine a distinct ''grade'' of organization—i.e. a 'level of complexity', measured in terms of how differentiated their organ systems are into distinct regions or sub-organs—with a distinct ''type'' of construc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
