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Hiatodoris
''Hiatodoris'' is a monotypic genus of sea slugs, specifically dorid nudibranchs. They are marine gastropod molluscs in the family Discodorididae. The only species is ''Hiatodoris fellowsi'' commonly known as the Snowball Sea Slug or Fellow's Nudibranch. It was previously known as ''Peltodoris fellowsi''. Description & Anatomy ''Hiatodoris fellowsi'' has an oval-like firm and white body, black rhinophores and gills, and white egg masses. It is a small species with a maximum size of about 51 mm. As most nudibranchs, this species is a hermaphrodite. The ejaculatory and vaginal ducts have their own orifices. It has a straight ejaculatory duct with a tight and convoluted vas deferens. Its prostate gland has no prostatic duct, but is large and finely lobulate. The spermatocyst and spermatheca are arranged semiserically, where the spermatheca is a little bigger than the spermatocyst and both are ovate. ''Hiatodoris fellowsi'' has a long vaginal duct with a lose and convolute open ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discodorididae
Discodorididae is a Taxonomy (biology), taxonomic family (biology), family of sea slugs, specifically dorid nudibranchs, marine (ocean), marine gastropod mollusks in the superfamily Doridoidea.Bouchet, P. (2011). Discodorididae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=1761 on 2011-08-23 Species in this family belong to the cryptobranch dorid nudibranchs, i.e. they are able to retract their gills into a gill pocket (cryptobranch = hidden gills). Most are small and hard to identify. Most are thought to feed at night on sponges, while during the day they search for dark areas or remain hidden under rocks. One example of a discodoridid is the "Pacific sea lemon" or "speckled sea lemon", ''Peltodoris nobilis'', which occurs off the coast of British Columbia to Baja California from low-tide waters to a depth of about 200 m. Not only is this species yellow with a bumpy surface, but it also gives off a strong fruit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Genus
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. Theoretical implications Monotypic taxa present several important theoretical challenges in biological classification. One key issue is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in a hierarchical system. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatheca
The spermatheca (pronounced : spermathecae ), also called ''receptaculum seminis'' (: ''receptacula seminis''), is an organ of the female reproductive tract in insects, e.g. ants, bees, some molluscs, Oligochaeta worms and certain other invertebrates and vertebrates. Its purpose is to receive and store sperm from the male or, in the case of hermaphrodites, the male component of the body. Spermathecae can sometimes be the site of fertilisation when the oocytes are sufficiently developed. Some species of animal have multiple spermathecae. For example, certain species of earthworms have four pairs of spermathecae—one pair each in the 6th, 7th, 8th, and 9th segments. The spermathecae receive and store the spermatozoa of another earthworm during copulation. They are lined with epithelium and are variable in shape: some are thin, heavily coiled tubes, while others are vague outpocketings from the main reproductive tract. It is one of the many variations in sexual reproduct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hachijō-jima
is a volcano, volcanic Islands of Japan, Japanese island in the Philippine Sea. It is about south of the special wards of Tokyo. It is part of the Izu Islands, Izu archipelago and within the Fuji-Hakone-Izu National Park. Its only municipality is Hachijō, Tokyo, Hachijō. On 1 March 2018, its population was 7,522 people living on 63 km2. Some inhabitants speak Hachijō language, which is considered an endangered language and the number of speakers is unknown. The island has been inhabited since the Jōmon period, and was used as a place of exile during the Edo period. In modern times, it has been used for farming sugarcane and housing a secret submarine base during World War II; it is now a tourist destination within Japan. Hachijō-jima receives about of precipitation annually. With a humid subtropical climate, and an average high temperature of , the island and the surrounding ocean support a wide variety of sea life, birds, mammals, plants, and other life. The talles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henderson Island (Pitcairn Islands)
Henderson Island is an uninhabited island in the south Pacific Ocean. It is part of the Pitcairn Islands, Pitcairn Island Group, together with Pitcairn Island, Pitcairn, Oeno Island, Oeno, and Ducie Island, Ducie Islands. Measuring , it has an area of and is located northeast of Pitcairn Island, which is the only inhabited island of the group. It has poor soil and little fresh water, and is unsuitable for agriculture. There are three beaches on the northern end and the remaining coast comprises steep (mostly undercut) cliffs up to in height. In 1902, it was annexed to the Pitcairn Islands colony, which is now a British Overseas Territories, British Overseas Territory. Henderson is one of the last two raised coral atolls in the world whose ecosystems remain relatively unaffected by human contact, along with Aldabra in the Indian Ocean. In 1988, it was designated a World Heritage Site by the United Nations. Ten of its 51 flowering plants, all four of its land birds and about a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaiian Islands
The Hawaiian Islands () are an archipelago of eight major volcanic islands, several atolls, and numerous smaller islets in the Pacific Ocean, North Pacific Ocean, extending some from the Hawaii (island), island of Hawaii in the south to northernmost Kure Atoll. Formerly called the Sandwich Islands by Europeans, the present name for the archipelago is derived from the name of its largest island, Hawaii. The archipelago sits on the Pacific Plate. The islands are exposed peaks of a great undersea mountain range known as the Hawaiian–Emperor seamount chain, formed by volcano, volcanic activity over the Hawaiian hotspot. The islands are about from the nearest continent and are part of the Polynesia subregion of Oceania. The U.S. state of Hawaii occupies the archipelago almost in its entirety (including the mostly uninhabited Northwestern Hawaiian Islands), with the sole exception of Midway Atoll (a United States Minor Outlying Island). Hawaii is the only U.S. state that is sit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east. At in area (as defined with a southern Antarctic border), the Pacific Ocean is the largest division of the World Ocean and the hydrosphere and covers approximately 46% of Earth's water surface and about 32% of the planet's total surface area, larger than its entire land area ().Pacific Ocean . ''Encyclopædia Britannica, Britannica Concise.'' 2008: Encyclopædia Britannica, Inc. The centers of both the Land and water hemispheres, water hemisphere and the Western Hemisphere, as well as the Pole of inaccessi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flange
A flange is a protruded ridge, lip or rim (wheel), rim, either external or internal, that serves to increase shear strength, strength (as the flange of a steel beam (structure), beam such as an I-beam or a T-beam); for easy attachment/transfer of contact force with another object (as the flange on the end of a pipe (fluid conveyance), pipe, steam cylinder, etc., or on the lens mount of a camera); or for stabilizing and guiding the movements of a machine or its parts (as the inside flange of a railroad car, rail car or tram train wheel, wheel, which keep the wheels from derailment, running off the rail profile, rails). Flanges are often attached using bolts in the pattern of a bolt circle. Flanges play a pivotal role in piping systems by allowing easy access for maintenance, inspection, and modification. They provide a means to connect or disconnect Pipe (fluid conveyance), pipes and equipment without the need for welding, which simplifies installation and reduces downtime during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamate
The hamate bone (from Latin language, Latin wiktionary:hamatus, hamatus, "hooked"), or unciform bone (from Latin language, Latin ''wikt:uncus, uncus'', "hook"), Latin os hamatum and occasionally abbreviated as just hamatum, is a bone in the human wrist readily distinguishable by its wedge shape and a hook-like process ("hamulus") projecting from its Radioulnar, palmar surface. Structure The hamate is an irregularly shaped carpal bone found within the hand. The hamate is found within the distal row of carpal bones, and abuts the metacarpals of the little finger and ring finger. Adjacent to the hamate on the ulnar side, and slightly proximal and ulnar to it, is the pisiform bone. Adjacent on the radial side is the capitate, and proximal is the lunate bone. Surfaces The hamate bone has six surfaces: * The ''superior'', the apex of the wedge, is narrow, convex, smooth, and articulates with the lunate bone, lunate. * The ''inferior'' articulates with the fourth and fifth metacarpal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radula
The radula (; : radulae or radulas) is an anatomical structure used by mollusks for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus. The radula is unique to the mollusks, and is found in every class of mollusk except the bivalves, which instead use cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs. The arrangement of teeth ( denticles) on the radular ribbon varies considerably from one group to another. In most of the more ancient lineages of gastropods, the radula is used to graze, by scraping diatoms and other microscopic algae off rock surfaces and other substrates. Predatory marine snails such as the Naticidae use the radula plus an acidic secretion to bore through the shell of other mollusks. Other predatory marine snails, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mucous Gland
Mucous glands, also known as muciparous glands, are found in several different parts of the body, and they typically stain lighter than serous glands during standard histological preparation. Most are multicellular, but goblet cells are single-celled glands. Mucous salivary glands The mucous salivary glands are similar in structure to the buccal and labial glands. They are found especially at the back part behind the vallate papillae, but are also present at the apex and marginal parts. In this connection, the anterior lingual glands require special notice. They are situated on the under surface of the apex of the tongue, one on either side of the frenulum, where they are covered by a fascicle of muscular fibers derived from the styloglossus and inferior longitudinal muscles. They produce a glycoprotein, mucin that absorbs water to form a sticky secretion called mucus. They are from 12 to 25 mm. long, and about 8 mm. broad, and each opens by three or four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
