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Hausera
''Hausera'' is a subterranean genus of planarian from Brazil. It contains only the single species ''Hausera hauseri''. It is the first cave-dwelling member of the suborder Cavernicola to have been observed in South America. Etymology Both the genus and species were named after Josef Hauser, a researcher of freshwater flatworms. Description Specimens are long and wide. The pharynx is long, and along with the gonopore is located in the hindmost third of the body. While it lacks eyes, the head has a pair of ciliated sensory organs approximately 140 µm back from the body's anterior end. The intestine extends into the brain and connects with the reproductive system via a genito-intestinal duct. The testicular follicles are arranged in uneven rows near the margins of the body, and the ovaries are located behind but in proximity to the brain, approximately 0.6 millimeters behind the body's tip. The species is colorless. Range and habitat ''Hausera hauseri'' was found i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavernicola (worm)
Cavernicola is a suborder of planarians found mostly in freshwater habitats of caves, although some species occur on the surface. Description The main morphological feature that defines the suborder Cavernicola is the placement of their ovaries. They are located more posteriorly than in other planarians, which usually have them close to the brain. The copulatory apparatus has a copulatory bursa in most species, although in some it is absent and is replaced by a connection to the intestine. Taxonomy The suborder Cavernicola was originally erected for the family Dimarcusidae Dimarcusidae is a family of triclads found mostly in freshwater habitats of caves, although at least one species, '' Rhodax evelinae'', occurs in surface waters. Currently the family contains only seven species distributed in five genera, althou ... due to its unusual morphological features that did not match those of the other planarian suborders. Recently, the discovery of another unusual cave spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rio Grande Do Norte
Rio Grande do Norte (, , ) is one of the states of Brazil. It is located in the northeastern region of the country, forming the northeasternmost tip of the South American continent. The name literally translates as "Great Northern River", referring to the mouth of the Potengi River. The capital and largest city is Natal. The state has 410 km (254 mi) of sandy beaches and contains Rocas Atoll, the only atoll the Atlantic Ocean. The main economic activity is tourism, followed by the extraction of petroleum (the second largest producer in the country), agriculture, fruit growing and extraction of minerals, including considerable production of seasalt, among other economic activities. The state is home to 1.7% of the Brazilian population and produces 1% of the country's GDP. In 2000-17 the murder rate rose by 655%, making Rio Grande do Norte the state with the highest murder rate in Brazil: 63.9 per 100,000. Tourist attractions in the state include the Cashew of Pirang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricladida
A planarian is one of the many flatworms of the traditional class Turbellaria. It usually describes free-living flatworms of the order Tricladida (triclads), although this common name is also used for a wide number of free-living platyhelminthes. Planaria are common to many parts of the world, living in both saltwater and freshwater ponds and rivers. Some species are terrestrial and are found under logs, in or on the soil, and on plants in humid areas. The triclads are characterized by triply branched intestine and anteriorly situated ovaries, next to the brain. Today the order Tricladida is split into three suborders, according to their phylogenetic relationships: Maricola, Cavernicola and Continenticola. Formerly, the Tricladida was split according to habitats: Maricola, which is marine; Paludicola which inhabits freshwater; and Terricola, which is land-dwelling. Planaria exhibit an extraordinary ability to regenerate lost body parts. For example, a planarian split lengt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suborder
Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ZooKeys
''ZooKeys'' is a peer-reviewed open access scientific journal covering zoological taxonomy, phylogeny, and biogeography. It was established in 2008 and the editor-in-chief is Terry Erwin (Smithsonian Institution). It is published by Pensoft Publishers. ''ZooKeys'' provides all new taxa to the Encyclopedia of Life on the day of publication. See also * ''Zootaxa ''Zootaxa'' is a peer-reviewed scientific mega journal for animal taxonomists. It is published by Magnolia Press (Auckland, New Zealand). The journal was established by Zhi-Qiang Zhang in 2001 and new issues are published multiple times a week. ...'' References External links * * * Creative Commons Attribution-licensed journals English-language journals Open access journals Publications established in 2008 Zoology journals Pensoft Publishers academic journals Continuous journals {{zoo-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Josef Hauser (zoologist)
Josef Hauser S. J. (January 31, 1920 – March 10, 2004) was a Hungarian zoologist and Jesuit priest. Life Josef Hauser was born in 1920 in southern Hungary. During his childhood and adolescence, he studied in a Jesuit school. From 1939 to 1941 he went to the novitiate of the Society of Jesus in Budapest. There, he had much contact with physicians, but they struggle to understand each other due to language differences. Hauser, however, became interested in Medicine and told the master of the novices about his decision to study the subject at the university. A letter was sent to Rome to announce Hauser's interest, but the idea was rejected. He was then oriented to study natural history in order to "learn everything that physicians know".IHU Repórter: Pe. Josef Hauser ''IHU Online'', 84:39-41, 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flatworm
The flatworms, flat worms, Platyhelminthes, or platyhelminths (from the Greek πλατύ, ''platy'', meaning "flat" and ἕλμινς (root: ἑλμινθ-), ''helminth-'', meaning "worm") are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates. Unlike other bilaterians, they are acoelomates (having no body cavity), and have no specialized circulatory and respiratory organ (anatomy), organs, which restricts them to having flattened shapes that allow oxygen and nutrients to pass through their bodies by diffusion. The digestive cavity has only one opening for both ingestion (intake of nutrients) and egestion (removal of undigested wastes); as a result, the food cannot be processed continuously. In traditional medicinal texts, Platyhelminthes are divided into Turbellaria, which are mostly non-parasitic animals such as planarians, and three entirely parasitic groups: Cestoda, Trematoda and Monogenea; however, since the turbellarians have since been prove ... [...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 arranged as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonopore
A gonopore, sometimes called a gonadopore, is a genital pore in many invertebrates. Hexapods, including insects have a single common gonopore, except mayflies, which have a pair of gonopores. More specifically, in the unmodified female it is the opening of the common oviduct, and in the male, it is the opening of the ejaculatory duct. The position of the gonopore varies considerably between groups, but is generally constant within groups, allowing its position to be used as a "segmental marker". In Malacostraca, it is on the sixth thoracic segment; in Symphyla it is on the fourth trunk segment; in arachnids, it is on the second segment of the opisthosoma. In insects and centipedes, the gonopores are close to the animal's tail, while in millipedes they are on the third body segment behind the head, near the second pair of legs. See also * Gonopod * Gonopodium Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . The longest human chromosome, chromosome 1, is approximately in length. Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovaries
The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. The ovaries also secrete hormones that play a role in the menstrual cycle and fertility. The ovary progresses through many stages beginning in the prenatal period through menopause. It is also an endocrine gland because of the various hormones that it secretes. Structure The ovaries are considered the female gonads. Each ovary is whitish in color and located alongside the lateral wall of the uterus in a region called the ovarian fossa. The ovarian fossa is the region that is bounded by the external iliac artery and in front of the ureter and the internal iliac artery. This area is about 4 cm x 3 cm x 2 cm in size.Daftary, Shirish; Chakravarti, Sudip (2011). Manual of Obstetrics, 3rd Edition. Elsevier. pp. 1-16. . The ovarie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perennial Stream
A perennial stream is a stream that has continuous flow of surface water throughout the year in at least parts of its catchment during seasons of normal rainfall, Water Supply Paper 494. as opposed to intermittent river, one whose flow is intermittent. In the absence of irregular, prolonged or extreme drought, a perennial stream is a watercourse, or segment, element or emerging body of water which continually delivers groundwater. For example, an damming, artificial disruption of stream, variability in flow or stream selection associated with the activity in hydropower installations, do not affect this status. Perennial streams do not include stagnant water (stream pool, pools and puddle, waterholes), reservoirs, oxbow lake, cutoff lakes and ponds that persist throughout the year. All other streams, or parts of them, should be considered seasonal rivers or lakes. The stream can cycle from intermittent to perpetual through multiple iterations. Stream Definition The basic conc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
