|
Polysteganus Praeorbitalis
''Polysteganus praeorbitalis'', the Scotsman or Scotsman seabream, is a species of marine fish in the seabream family (Sparidae) of order Perciformes. It is native to Southern Africa. Description Body is oblong, robust, and slightly compressed, with one continuous dorsal fin. The caudal fin is slightly forked. It has a distinctive body shape, and is easily recognised. The forehead is steep, and adults have a prominent hump on the nape. The deep body tapers towards the tail. Eyes are small. Adults are mostly reddish pink to pale blue-green, with numerous blue dots on the upper body and pearly scales below the lateral line. There are usually some silvery to blue lines around the eyes. Juveniles may be more yellowish and have three brown longitudinal stripes. Attains , and . Common length: 35.0 cm Diagnostics The dorsal fin has 12 spines, followed by 10 rays. The anal fin has 8 rays. The pectoral fin is subequal to the head, and the ventral fin has 1 spine and 5 rays. The l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Günther
Albert Karl Ludwig Gotthilf Günther Fellow of the Royal Society, FRS, also Albert Charles Lewis Gotthilf Günther (3 October 1830 – 1 February 1914), was a German-born British zoologist, ichthyologist, and herpetologist. Günther is ranked the second-most productive reptile taxonomist (after George Albert Boulenger) with more than 340 reptile species described. Early life and career Günther was born in Esslingen am Neckar, Esslingen in Swabia (Württemberg). His father was a ''Stiftungs-Commissar'' in Esslingen and his mother was Eleonora Nagel. He initially schooled at the Stuttgart Gymnasium. His family wished him to train for the ministry of the Lutheran Church for which he moved to the University of Tübingen. A brother shifted from theology to medicine, and he, too, turned to science and medicine at Tübingen in 1852. His first work was "''Ueber den Puppenzustand eines Distoma''". He graduated in medicine with an M.D. from Tübingen in 1858, the same year in which he pub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Fin
Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous Homology may refer to: Sciences Biology *Homology (biology), any characteristic of biological organisms that is derived from a common ancestor *Sequence homology, biological homology between DNA, RNA, or protein sequences * Homologous chrom ... to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two endochondrally-derived bony girdles attached to bony radials. Dermal fin rays ( lepidotrichia) are positioned distally from the radials. There are three pairs of muscles each on the dorsal and ventral side of the pelvic fin girdle that abduct and adduct the fin from the body. Pelvic fin structures can be extremely specialized in actinopterygians. Gobiids and lumpsuckers modify their pelvic fins into a sucker disk that allow them to adhere to the substrate or climb structures, such as wat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IUCN Red List Of Threatened Species
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biological species. It uses a set of precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world. With its strong scientific base, the IUCN Red List is recognized as the most authoritative guide to the status of biological diversity. A series of Regional Red Lists are produced by countries or organizations, which assess the risk of extinction to species within a political management unit. The aim of the International Union for Conservation of Nature, IUCN Red List is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to reduce species extinction. According to International Unio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protogynous Hermaphrodite
Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants. Sequential hermaphroditism occurs when the individual changes its sex at some point in its life. In particular, a sequential hermaphrodite produces eggs (female gametes) and sperm (male gametes) at different stages in life. Species that can undergo these changes from one sex to another do so as a normal event within their reproductive cycle that is usually cued by either social structure or the achievement of a certain age or size. In animals, the different types of change are male to female (protandry or protandrous hermaphroditism), female to male (protogyny or protogynous hermaphroditism), bidirectional (serial or bidirectional hermaphroditism). Both protogynous and protandrous hermaphroditism allow the organism to switch between functional male and functional female. Bidirectional hermaphrodites have the capacity for sex change in either direc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beira, Mozambique
Beira is the capital and largest city of Sofala Province, where the Pungwe River meets the Indian Ocean, in the central region of Mozambique. It is the fourth-largest city by population in Mozambique, after Maputo, Matola and Nampula. Beira had a population of 397,368 in 1997, which grew to 530,604 in 2019. A coastal city, it holds the regionally significant Port of Beira, which acts as a gateway for both the central interior portion of the country as well as the land-locked nations of Zimbabwe, Zambia and Malawi. Originally called Chiveve after a local river, it was renamed Beira to honour the Portuguese Crown prince Dom Luís Filipe (titled Prince of Beira, itself referring to the traditional Portuguese province of Beira), who had visited Mozambique in the early 1900s. It was first developed by the Portuguese Mozambique Company in the 19th century, supplanting Sofala as the country's main port. It was then directly developed by the Portuguese colonial government ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eastern Cape
The Eastern Cape is one of the provinces of South Africa. Its capital is Bhisho, but its two largest cities are East London and Gqeberha. The second largest province in the country (at 168,966 km2) after Northern Cape, it was formed in 1994 out of the Xhosa homelands or bantustans of Transkei and Ciskei, together with the eastern portion of the Cape Province. The central and eastern part of the province is the traditional home of the indigenous Xhosa people. In 1820 this area which was known as the Xhosa Kingdom began to be settled by Europeans who originally came from England and some from Scotland and Ireland. Since South Africa's early years, many Xhosas believed in Africanism and figures such as Walter Rubusana believed that the rights of Xhosa people and Africans in general, could not be protected unless Africans mobilized and worked together. As a result, the Eastern Cape is home to many anti-apartheid leaders such as Robert Sobukwe, Oliver Tambo, Nelson Mandela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algoa Bay
Algoa Bay is a maritime bay in the Eastern Cape, South Africa. It is located in the east coast, east of the Cape of Good Hope. Algoa Bay is bounded in the west by Cape Recife and in the east by Cape Padrone. The bay is up to deep. The harbour city of Port Elizabeth is situated adjacent to the bay, as is the Port of Ngqura deep water port facility. History The Portuguese explorer Bartolomeu Dias was the first European to reach Algoa Bay in 1488, where he planted a wooden cross on a small island now called St Croix or Santa Cruz island. He gave the bay a name meaning "Bay of the Rock", which was changed in Portugal to ''Bahia de Lagoa'' or Bay of the Lagoon, and which eventually became Algoa Bay. Joshua Slocum talks about Algoa Bay in his book ' Sailing Alone Around the World' (this is not an historical account): Nautical charts of the bay caution mariners that "projectiles and badly corroded mustard gas containers have been found in the area between Cape St Francis and Bir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Length
Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish measured from the tip of the snout to the posterior end of the last vertebra or to the posterior end of the midlateral portion of the hypural plate. Simply put, this measurement excludes the length of the caudal (tail) fin. * Total length (TL) is the length of a fish measured from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body. Standard length measurements are used with Teleostei (most bony fish), while total length measurements are used with Myxini (hagfish), Petromyzontiformes (lampreys), and (usually) Elasmobranchii (shark Sharks are a group of elasmobranch fish characterize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Measurement
Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish measured from the tip of the snout to the posterior end of the last vertebra or to the posterior end of the midlateral portion of the hypural plate. Simply put, this measurement excludes the length of the caudal (tail) fin. * Total length (TL) is the length of a fish measured from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body. Standard length measurements are used with Teleostei (most bony fish), while total length measurements are used with Myxini ( hagfish), Petromyzontiformes ( lampreys), and (usually) Elasmobranchii (shark Sharks are a group of elasmobranch fish chara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill Arch
Branchial arches, or gill arches, are a series of bony "loops" present in fish, which support the gills. As gills are the primitive condition of vertebrates, all vertebrate embryos develop pharyngeal arches, though the eventual fate of these arches varies between taxa. In jawed fish, the first arch develops into the jaws, the second into the hyomandibular complex, with the posterior arches supporting gills. In amphibians and reptiles, many elements are lost including the gill arches, resulting in only the oral jaws and a hyoid apparatus remaining. In mammals and birds, the hyoid is still more simplified. All basal vertebrates breathe with gills. The gills are carried right behind the head, bordering the posterior margins of a series of openings from the esophagus to the exterior. Each gill is supported by a cartilaginous or bony gill arch. Bony fish have four pairs of arches, cartilaginous fish have five to seven pairs, and primitive jawless fish have seven. The vertebr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill Rakers
Gill rakers in fish are bony or cartilaginous processes that project from the branchial arch (gill arch) and are involved with suspension feeding tiny prey. They are not to be confused with the gill filaments that compose the fleshy part of the gill used for gas exchange. Rakers are usually present in two rows, projecting from both the anterior and posterior side of each gill arch. Rakers are widely varied in number, spacing, and form. By preventing food particles from exiting the spaces between the gill arches, they enable the retention of food particles in filter feeders. The structure and spacing of gill rakers in fish determines the size of food particles trapped, and correlates with feeding behavior. Fish with densely spaced, elongated, comb-like gill rakers are efficient at filtering tiny prey, whereas carnivores and omnivores often have more widely spaced gill rakers with secondary projections. Because gill raker characters often vary between closely related taxa, they ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Line
The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial cells, known as hair cells, which respond to displacement caused by motion and transduce these signals into electrical impulses via excitatory synapses. Lateral lines serve an important role in schooling behavior, predation, and orientation. Fish can use their lateral line system to follow the vortices produced by fleeing prey. Lateral lines are usually visible as faint lines of pores running lengthwise down each side, from the vicinity of the gill covers to the base of the tail. In some species, the receptive organs of the lateral line have been modified to function as electroreceptors, which are organs used to detect electrical impulses, and as such, these systems remain closely linked. Most amphibian larvae and some fully aquati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Gill Arch")
