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Leocratides Kimuraorum
''Leocratides kimuraorum'' (Japanese: ''Kimura-hanakago-otohime-gokai'') is a species of marine worm belonging to Hesionidae, which is known for the intensity of its intraspecific fighting. Its body is nearly translucent and up to long. This bristle worm species lives off the coast of Japan, inside sponges deep. ''L. kimuraorum'' produces one of the loudest sounds in the ocean, a popping sound, at 157 dB (at a reference pressure of 1 μPa) at 1 m, with frequencies in the 1–100 kHz range, similar to the snapping shrimps. Discovery The worm was first discovered in 2017. The holotype specimen was found at a depth of , south of Honshu, off the coast of Shima, Mie The holotype was long and wide. Discovered in Sagami Bay, the Japanese name of the worm is ''Kimura-hanakago-otohime-gokai''. Taxonomy Other members of the genus '' Leocratides'' — worms inhabiting '' Aphrocallistes'' sponges — include ''L. ehlersi'' and ''L. filamentosus''. ''Leocratides kimuraorum'' can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Worm
Any worm that lives in a marine environment is considered a marine worm. Marine worms are found in several different phyla, including the Platyhelminthes, Nematoda, Annelida (segmented worms), Chaetognatha, Hemichordata, and Phoronida. For a list of marine animals that have been called "sea worms", see sea worm. Reproduction Marine worms exhibit numerous types of reproduction, both sexually and asexually. Asexually many are able to reproduce via budding or regeneration. This regeneration is most notably studied in Plathelminths or Triclad, known for being one of the earliest animals to be studied for its regenerative capabilities. Marine worms will also sexually reproduce, internally and externally, with some releasing spawn into the ocean currents. This is in opposition to the much more internal and invasive method displayed by flat-worms called Penis fencing where hermaphroditic organisms will flight to try and impregnate their opponent while avoiding becoming impregnate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leocratides
''Leocratides'' is a genus of marine hesionid polychaete worms dwelling in hexactinellid sponges. Names and taxonomy A superseded synonym of the genus is ''Leocrates''. Its parent group is Hesionini, a tribe in the subfamily Hesioninae. The three known species include '' L. kimuraorum'', ''L. ehlersi'', and ''L. filamentosus''. The Japanese name of ''Leocratides'' is ''hanakago-otohime-gokai-zoku''. History of research The taxonomy of the genus has been debated by invertebrate zoologists since ''L. filamentosus'' was first discovered by the German zoologist Ernst Ehlers in 1908 on the deep-sea Valdivia Expedition. When R. Horst described ''L. ehlersi'' for the first time in 1921, examining an old specimen from the Siboga expedition, he suggested that the two known species were distinguished by having one or two dorsal jaw plates. Based on a 1926 analysis however, H. Augener argued that ''L. ehlersi'' was a junior synonym of ''L. filamentosus'', and that both had tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllodocida
Phyllodocida is an order of polychaete worms in the subclass Aciculata. These worms are mostly marine, though some are found in brackish water. Most are active benthic creatures, moving over the surface or burrowing in sediments, or living in cracks and crevices in bedrock. A few construct tubes in which they live and some are pelagic, swimming through the water column. There are estimated to be more than 4,600 accepted species in the order. Characteristics Phyllodocida are segmented worms and range in size from a few millimetres long to over a metre. Each segment bears a pair of paddle-like parapodia. The prostomium generally has one or two pairs of eyes, a dorsal pair of antennae, a ventral pair of sensory palps and a pair of organs on the neck. The peristomium is a ring, often hidden dorsally by the prostomium and the first segment. There is a muscular proboscis with one or more pairs of jaws. The next few segments tend to differ from those further back in having enlarged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polychaetes
Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. More than 10,000 species are described in this class. Common representatives include the lugworm (''Arenicola marina'') and the sandworm or clam worm ''Alitta''. Polychaetes as a class are robust and widespread, with species that live in the coldest ocean temperatures of the abyssal plain, to forms which tolerate the extremely high temperatures near hydrothermal vents. Polychaetes occur throughout the Earth's oceans at all depths, from forms that live as plankton near the surface, to a 2- to 3-cm specimen (still unclassified) observed by the robot ocean probe ''Nereus'' at the bottom of the Challenger Deep, the deepest known spot in the Earth's oceans. Only 168 species (less than 2% of all polychaetes) are known from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavitation
Cavitation is a phenomenon in which the static pressure of a liquid reduces to below the liquid's vapour pressure, leading to the formation of small vapor-filled cavities in the liquid. When subjected to higher pressure, these cavities, called "bubbles" or "voids", collapse and can generate shock waves that may damage machinery. These shock waves are strong when they are very close to the imploded bubble, but rapidly weaken as they propagate away from the implosion. Cavitation is a significant cause of wear in some engineering contexts. Collapsing voids that implode near to a metal surface cause cyclic stress through repeated implosion. This results in surface fatigue of the metal causing a type of wear also called "cavitation". The most common examples of this kind of wear are to pump impellers, and bends where a sudden change in the direction of liquid occurs. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its structure varies across species. The pharynx carries food and air to the esophagus and larynx respectively. The flap of cartilage called the epiglottis stops food from entering the larynx. In humans, the pharynx is part of the digestive system and the conducting zone of the respiratory system. (The conducting zone—which also includes the nostrils of the nose, the larynx, trachea, bronchi, and bronchioles—filters, warms and moistens air and conducts it into the lungs). The human pharynx is conventionally divided into three sections: the nasopharynx, oropharynx, and laryngopharynx. It is also important in vocalization. In humans, two sets of pharyngeal muscles form the pharynx and determine the shape of its lumen. They are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexactinellid
Hexactinellid sponges are sponges with a skeleton made of four- and/or six-pointed siliceous spicules, often referred to as glass sponges. They are usually classified along with other sponges in the phylum Porifera, but some researchers consider them sufficiently distinct to deserve their own phylum, Symplasma. Some experts believe glass sponges are thlongest-lived animals on earth these scientists tentatively estimate a maximum age of up to 15,000 years. Biology Glass sponges are relatively uncommon and are mostly found at depths from below the sea level. Although the species '' Oopsacas minuta'' has been found in shallow water, others have been found much deeper. They are found in all oceans of the world, although they are particularly common in Antarctic and Northern Pacific waters. They are more-or-less cup-shaped animals, ranging from in height, with sturdy lattice-like internal skeletons made up of fused spicules of silica. The body is relatively symmetrical, with a large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seta
In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. They help, for example, earthworms to attach to the surface and prevent backsliding during peristaltic motion. These hairs make it difficult to pull a worm straight from the ground. Setae in oligochaetes (a group including earthworms) are largely composed of chitin. They are classified according to the limb to which they are attached; for instance, notosetae are attached to notopodia; neurosetae to neuropodia. Crustaceans have mechano- and chemosensory setae. Setae are especially present on the mouthparts of crustaceans and can also be found on grooming limbs. In some cases, setae are modified into scale like structures. Setae on the legs of krill and other small crustaceans help them to gather phytoplankton. It captures them and allow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaeta
A chaeta or cheta (from Greek χαίτη “crest, mane, flowing hair"; plural: chaetae) is a chitinous bristle or seta found in annelid worms, (although the term is also frequently used to describe similar structures in other invertebrates such as arthropods). Polychaete annelids, ('polychaeta' literally meaning "many bristles") are named for their chaetae. In Polychaeta, chaetae are found as bundles on the parapodia, paired appendages on the side of the body. The chaetae are epidermal extracellular structures, and clearly visible in most polychaetes. They are probably the best studied structures in these animals. Use in taxonomy and identification The ultrastructure of chaetae is fundamentally similar for all taxa but there is vast diversity in chaetal morphology. Moreover, chaetae bear precise characters for determination of species and taxonomic assessment. The shape, absolute and relative size, number, position, ornamentation and type are important taxonomic characters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloud Sponge
The cloud sponge ''(Aphrocallistes vastus)'' is a species of sea sponge in the class Hexactinellida. It is a deep-water reef-forming animal. The species was first described by F.E. Schulze in 1886. Description The cloud sponge takes the form of a large cup with an irregularly folded wall about thick. This is pierced by many pores about wide and covered by a thin dermal membrane. The skeletal elements form a lattice-like structure made up of fused spicules of silica. These mesh together and project into the adjoining canals. There is a fir-tree like concentration of spicules running through the body wall with the branches either having rounded or knobbly ends. The form of the sponge varies according to the location in which it is found. It often has a mitten-like structure or may be tall and cylindrical or bowl-like but in areas with strong currents can be dense and compact. Distribution The cloud sponge is found in the northern Pacific Ocean. Its range includes Japan, Siber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagami Bay
lies south of Kanagawa Prefecture in Honshu, central Japan, contained within the scope of the Miura Peninsula, in Kanagawa, to the east, the Izu Peninsula, in Shizuoka Prefecture, to the west, and the Shōnan coastline to the north, while the island of Izu Ōshima marks the southern extent of the bay. It lies approximately southwest of the capital, Tokyo. Cities on the bay include Odawara, Chigasaki, Fujisawa, Hiratsuka, Itō, and Kamakura. History The center of the Great Kantō earthquake in 1923 was deep beneath Izu Ōshima Island in Sagami Bay. It devastated Tokyo, the port city of Yokohama, and the surrounding prefectures of Chiba, Kanagawa, and Shizuoka, and caused widespread damage throughout the Kantō region. The shallow nature of the seabed on the north of the bay, and the funnelling effect of tsunami and typhoon wave energy, contributed to certain parts of the Shonan coast having suffered considerable damage, including the destruction of the Kō ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesionidae
Hesionidae are a family of phyllodocid "bristle worms" (class Polychaeta). They are (like almost all polychaetes) marine organisms. Most are found on the continental shelf; '' Hesiocaeca methanicola'' is found on methane ice, where it feeds on bacterial biofilms. A characteristic apomorphy of the Hesionidae are the cirrophores of the anterior segments, which are well-developed cup-like sheaths; the cirri of the subsequent segments insert into the parapodia directly, or with just a vestigial cirrophore. Systematics As phyllodocids, the Hesionidae belong to the order Aciculata, one of the three main clades of polychaetes. They appear to be part of the basal radiation of the main lineage of phyllodocids, alongside such families as the ragworms (Nereididae), the Pilargidae and Sphaerodoridae which are closely related to each other, the very ancient Syllidae, and perhaps the more advanced catworms (Nephtyidae). Numerous genera are still treated as Hesionidae ''incer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
