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Pomphorhynchus Laevis
''Pomphorhynchus laevis'' is an endo-parasitic acanthocephalan worm, with a complex life cycle, that can modify the behaviour of its intermediate host, the freshwater amphipod ''Gammarus pulex''. ''P. laevis'' does not contain a digestive tract and relies on the nutrients provided by its host species. In the fish host this can lead to the accumulation of lead in ''P. laevis'' by feeding on the bile of the host species. Life cycle and host species ''Pomphorhynchus laevis'' is a parasite with a complex life cycle, meaning that it needs multiple host species to complete it. The female releases eggs containing acanthor that are then ingested by an arthropod. The acanthor is then released from the egg and becomes acanthella which penetrate the host's gut wall and transforms into the infective cystacanth stage which presents as a cyst. The larval stages (cystacanths) reside in the hemocoel of its intermediate host, gammarids. From them it is trophically transmitted to fish. Several ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthocephala
Acanthocephala ( Greek , ' 'thorn' + , ' 'head') is a group of parasitic worms known as acanthocephalans, thorny-headed worms, or spiny-headed worms, characterized by the presence of an eversible proboscis, armed with spines, which it uses to pierce and hold the gut wall of its host. Acanthocephalans have complex life cycles, involving at least two hosts, which may include invertebrates, fish, amphibians, birds, and mammals. About 1,420 species have been described. The Acanthocephala were long thought to be a discrete phylum. Recent genome analysis has shown that they are descended from, and should be considered as, highly modified rotifers. This unified taxon is sometimes known as Syndermata, or simply as Rotifera, with the acanthocephalans described as a subclass of a rotifer class Hemirotatoria. History The earliest recognisable description of Acanthocephala – a worm with a proboscis armed with hooks – was made by Italian author Francesco Redi (1684). In 1771 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telestes Souffia
The souffia, Western riffle dace, telestes, vairone or western vairone (''Telestes souffia'') is a species of freshwater ray-finned fish belonging to the family Leuciscidae, which includes the daces, Eurasian minnows and related fishes. This species is found in rivers that drain into the Mediterranean, as well as the Rhine and Danube catchments. Taxonomy The souffia was first formally described as ''Leuciscus souffia'' in 1827 by the French naturalist Antoine Risso with its type locality given as the River Var in France. This taxon is now regarded as a valid species in the genus ''Telestes'' in the subfamily Leuciscinae of the family Leuciscidae. Etymology The souffia belongs to the genus ''Telestes'', a name which was coined by Charles Lucien Bonaparte who did not explain its etymology, although it may be from ''teléstēs'', the Greek for "completer" or "finisher", and if that is thecase then the allusion is not obvious. in 1877 David Starr Jordan suggested that the name been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gammarus Roeseli
''Gammarus roeselii'' is a species of freshwater amphipod native to Europe. Nomenclature Gervais described G. roeselii in 1835 under today's correct name G. roeselii GERVAIS , 1835. Since he wrote the description in Latin and used the Latinized name of the baron, i.e. "ROESELIUS", the genitive form is roeselii. Therefore the spelling with double i is taxonomically correct, but often the spelling with only one i is often used. Description ''Gammarus roeselii'' adult males reach a length of up to 22 mm; females are smaller than males. The species is distinct from many other common amphipods due to the spines on its fifth through seventh pereiopods. The color of ''G. roeselii'' individuals can vary from green to brown, gray, or yellow, and some have reddish markings on parts of their carapaces. Distribution ''Gammarus roeselii'' originated in the Balkan area of Europe, and appears to have populated the Pannonian Basin as a glacial refuge before expanding into central an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyloric Caeca
Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish are also known as asteroids due to being in the class Asteroidea. About 1,900 species of starfish live on the seabed in all the world's oceans, from warm, tropical zones to frigid, polar regions. They are found from the intertidal zone down to abyssal depths, at below the surface. Starfish are marine invertebrates. They typically have a central disc and usually five arms, though some species have a larger number of arms. The aboral or upper surface may be smooth, granular or spiny, and is covered with overlapping plates. Many species are brightly coloured in various shades of red or orange, while others are blue, grey or brown. Starfish have tube feet operated by a hydraulic system and a mouth at the centre of the oral or lower surfac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Round Goby
The round goby (''Neogobius melanostomus'') is a euryhaline bottom-dwelling species of fish of the family (biology), family Gobiidae. It is native to Central Eurasia, including the Black Sea and the Caspian Sea. Round gobies have established large non-native populations in the Baltic Sea, several major Eurasian rivers, and the North American Great Lakes. Characteristics Round gobies are small, soft-bodied fish characterized by a distinctive black spot on the first dorsal fin. The eyes are large and protrude slightly from the top of the head and, like most gobies, the pelvic fins are fused to form a single disc (shaped like a suction cup) on the belly. Round gobies range in length from , with a maximum size of . They weigh between , their weight increasing with age. Male round gobies are larger than females. Juvenile round gobies (less than one year old) are grey. Upon maturation, round gobies become mottled with grey, black, brown, and olive green markings. Adult male round gobies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmo Trutta
The brown trout (''Salmo trutta'') is a species of salmonid ray-finned fish and the most widely distributed species of the genus ''Salmo'', endemic to most of Europe, West Asia and parts of North Africa, and has been widely introduced species, introduced globally as a game fish, even becoming 100 of the World's Worst Invasive Alien Species, one of the world's worst invasive species outside of its native range. Brown trout are highly adaptable and have evolved numerous ecotypes/subspecies. These include three main ecotypes: a riverine ecotype called river trout or Salmo trutta fario, ''Salmo trutta'' morpha ''fario''; a lacustrine ecotype or ''S. trutta'' morpha ''lacustris'', also called the lake trout (not to be confused with the lake trout in North America); and anadromous populations known as the sea trout or ''S. trutta'' morpha ''trutta'', which upon adulthood migrate downstream to the oceans for much of its life and only returns to fresh water to spawn (biology), spawn in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gasterosteus Aculeatus
The three-spined stickleback (''Gasterosteus aculeatus'') is a fish native to most inland and coastal waters north of 30°N. It has long been a subject of scientific study for many reasons. It shows great morphological variation throughout its range, ideal for questions about evolution and population genetics. Many populations are anadromous (they live in seawater but breed in fresh or brackish water) and very tolerant of changes in salinity, a subject of interest to physiologists. It displays elaborate breeding behavior (defending a territory, building a nest, taking care of the eggs and fry) and it can be social (living in shoals outside the breeding season) making it a popular subject of inquiry in fish ethology and behavioral ecology. Its antipredator adaptations, host-parasite interactions, sensory physiology, reproductive physiology, and endocrinology have also been much studied. Facilitating these studies is the fact that the three-spined stickleback is easy to find in natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cottus Gobio
The European bullhead (''Cottus gobio'') is a freshwater fish that is widely distributed in Europe, mainly in rivers. It is a member of the family Cottidae, a type of sculpin. It is also known as the miller's thumb, freshwater sculpin, common bullhead, and cob. The European bullhead is a small demersal fish that lives both in cold, clear, fast-flowing small streams and in middle-sized rivers. It also occurs on gravelly shores of cold lakes. Further, it thrives in diluted brackish water of the Northern Baltic Sea. Description The bullhead has a large broad head and tapering body, large fins and a rounded tail. The eyes are located near the top of the head. To the distinction from the other freshwater sculpin species found in Northern Europe, it can be told from the alpine bullhead ''Cottus poecilopus'' by the fact that the rays of its pelvic fins are of similar lengths while the first and last rays are longer in the alpine bullhead. It can be distinguished from the fourhorn scul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perca Fluviatilis
The European perch (''Perca fluviatilis''), also known as the common perch, redfin perch, big-scaled redfin, English perch, Euro perch, Eurasian perch, Eurasian river perch, Hatch, poor man's rockfish or in Anglophone parts of Europe, simply the perch, is a predatory freshwater fish native to Europe and North Asia. It is the type species of the genus '' Perca''. The perch is a popular game fish for recreational anglers, and has been widely introduced beyond its native Eurasian habitats into Australia, New Zealand and South Africa. Known locally simply as "redfin", they have caused substantial damage to native fish populations in Australia and have been proclaimed a noxious species in New South Wales. Taxonomy The first scientific description of the river perch was made by Peter Artedi in 1730. He defined the basic morphological signs of this species after studying perch from Swedish lakes. Artedi described its features, counting the fin rays scales and vertebrae of the typic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ameiurus Melas
The black bullhead or black bullhead catfish (''Ameiurus melas'') is a species of bullhead catfish. Like other bullhead catfish, it has the ability to thrive in waters that are low in oxygen, brackish, turbid, and/or very warm. It also has barbels located near its mouth, a broad head, spiny fins, and no scales. It can be identified from other bullheads as the barbels are black, and it has a tan crescent around the tail. Its caudal fin is truncated (squared off at the corners). Like virtually all catfish, it is nocturnal, preferring to feed at night, although young feed during the day. It generally does not get as large as the channel or blue catfish, with average adult weights are in the range, and almost never as large as . It has a typical length of , with the largest specimen being , making it the largest of the bullheads. It is typically black or dark brown on the dorsal side of its body and yellow or white on the ventral side. Like most of the bullheads (and even flathead ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barbatula Barbatula
The stone loach (''Barbatula barbatula'') is a European species of fresh water ray-finned fish in the family Nemacheilidae. It is one of nineteen species in the genus ''Barbatula''. Stone loaches live amongst the gravel and stones of fast flowing water where they can search for food. The most distinctive feature of this small fish is the presence of barbels around the bottom jaw, which they use to detect their invertebrate prey. The body is a mixture of brown, green and yellow. Description The stone loach is a small, slender bottom-dwelling fish that can grow to a length of , but typically is around . Its eyes are situated high on its head and it has three pairs of short barbels on its lower jaw below its mouth. It has a rounded body that is not much laterally flattened and is a little less deep in the body than the spined loach (''Cobitis taenia'') and lacks that fish's spines beneath the eye. It has rounded dorsal and caudal fins with their tips slightly notched, but the spined ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
