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Cave Fish
Cavefish or cave fish is a generic term for fresh and brackish water fish adapted to life in caves and other underground habitats. Related terms are subterranean fish, troglomorphic fish, troglobitic fish, stygobitic fish, phreatic fish and hypogean fish.Romero, Aldemaro, editor (2001). ''The Biology of Hypogean Fishes.'' Developments in Environmental Biology of Fishes. Helfman, G.S. (2007). ''Fish Conservation: A Guide to Understanding and Restoring Global Aquatic Biodiversity and Fishery Resources'', pp. 41–42. Island Press. There are more than 200 scientifically described species of obligate cavefish found on all continents, except Antarctica. Although widespread as a group, many cavefish species have very small ranges and are seriously threatened.Fenolio, D.B.; Zhao, Y.; Niemiller, M.L.; and Stout, J. (2013). ''In-situ observations of seven enigmatic cave loaches and one cave barbel from Guangxi, China, with notes on conservation status.'' Speleobiology Notes 5: 19-33. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyprinidae - Phreatichthys Andruzzii
Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest vertebrate animal family in general with about 3,000 species, of which only 1,270 remain extant, divided into about 370 genera. Cyprinids range from about 12 mm in size to the giant barb (''Catlocarpio siamensis''). By genus and species count, the family makes up more than two-thirds of the ostariophysian order Cypriniformes. The family name is derived from the Greek word ( 'carp'). Biology and ecology Cyprinids are stomachless fish with toothless jaws. Even so, food can be effectively chewed by the gill rakers of the specialized last gill bow. These pharyngeal teeth allow the fish to make chewing motions against a chewing plate formed by a bony process of the skull. The pharyngeal teeth are unique to each species and are used by s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trogloxene
Trogloxenes or subtroglophiles, also called cave guests, are animal species which periodically live in underground habitats such as caves or at the very entrance, but cannot live exclusively in such habitats."Cave Plants and Animals". 9 December Among many scientists, trogloxenes and subtroglophile have slightly different but closely related meanings, with the former covering species that are occasional visitors to underground habitat and the latter species that live more permanently there, but have to go outside (for example, to find food). Both these are in contrast to troglobites, which strictly live in underground habitats. Examples of trogloxene/subtroglophile species are bats, rats, raccoons and some opiliones (this last group also has fully troglobitic species). Several extinct trogloxenes are known like cave bears, cave lions, cave leopards, and cave hyenas. Indications trusted by geologists and archaeologists combine to show that these animals lived there in the latter pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photophobia (biology)
In biology, photophobia (adjective: photophobic) is negative response to light. Photophobia is a behavior demonstrated by insects or other animals which seek to stay out of the light. In botany, the term photophobia/photophobic describes shade-loving plants that thrive in low light conditions. Photophobia (or photophobic response) may also refer to a negative phototaxis Phototaxis is a kind of taxis, or locomotory movement, that occurs when a whole organism moves towards or away from a stimulus of light. This is advantageous for phototrophic organisms as they can orient themselves most efficiently to receive ... or phototropism response. References Physiology {{biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congo Blind Barb
''Caecobarbus geertsi'', the African blind barb or Congo blind barb (known as ''Nzonzi a mpofo'' in the local Kikongo language, meaning "blind barb"), is a species of cyprinid fish. This threatened cavefish is only known from Democratic Republic of the Congo, and it is the only member of the monotypic genus ''Caecobarbus''. George Albert Boulenger described this fish in 1921 and it apparently lacks any close relatives in the Congo region. Despite its common name, "African blind barb", other blind cave cyprinids are indigenous to Africa, notably the Somalian '' Barbopsis devecchi'' and '' Phreatichthys andruzzii''. Range The Congo blind barb is found only in the Thysville Cave system, a part of the lower Congo River basin (notably Kwilu and Inkisi tributaries) in the Democratic Republic of the Congo. The area where found covers about , and is located at an altitude around above sea level. It was initially known from seven caves in the Thysville system and an additional seve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pineal Eye
A parietal eye, also known as a third eye or pineal eye, is a part of the epithalamus present in some vertebrates. The eye is located at the top of the head, is photoreceptive and is associated with the pineal gland, regulating circadian rhythmicity and hormone production for thermoregulation. The hole in the head which contains the eye is known as a pineal foramen or parietal foramen, since it is often enclosed by the parietal bones. Presence in various animals The parietal eye is found in the tuatara, most lizards, frogs, salamanders, certain bony fish, sharks, and lampreys. It is absent in mammals, but was present in their closest extinct relatives, the therapsids, suggesting it was lost during the course of the mammalian evolution due to it being useless in endothermic animals. It is also absent in the ancestrally endothermic ("warm-blooded") archosaurs such as birds. The parietal eye is also lost in ectothermic ("cold-blooded") archosaurs like crocodilians, and in turtles, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pineal Gland
The pineal gland, conarium, or epiphysis cerebri, is a small endocrine gland in the brain of most vertebrates. The pineal gland produces melatonin, a serotonin-derived hormone which modulates sleep patterns in both circadian and seasonal cycles. The shape of the gland resembles a pine cone, which gives it its name. The pineal gland is located in the epithalamus, near the center of the brain, between the two hemispheres, tucked in a groove where the two halves of the thalamus join. The pineal gland is one of the neuroendocrine secretory circumventricular organs in which capillaries are mostly permeable to solutes in the blood. Nearly all vertebrate species possess a pineal gland. The most important exception is a primitive vertebrate, the hagfish. Even in the hagfish, however, there may be a "pineal equivalent" structure in the dorsal diencephalon. The lancelet '' Branchiostoma lanceolatum'', an early chordate which is a close relative to vertebrates, also lacks a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swim Bladder
The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their current water depth without having to expend energy in swimming. Also, the dorsal position of the swim bladder means the center of mass is below the center of volume, allowing it to act as a stabilizing agent. Additionally, the swim bladder functions as a resonating chamber, to produce or receive sound. The swim bladder is evolutionarily homologous to the lungs. Charles Darwin remarked upon this in ''On the Origin of Species''.Darwin, Charles (1859''Origin of Species''Page 190, reprinted 1872 by D. Appleton. Darwin reasoned that the lung in air-breathing vertebrates had derived from a more primitive swim bladder. In the embryonic stages, some species, such as redlip blenny, have lost the swim bladder again, mostly bottom dwellers like the weather fish. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Scale
A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scales, which can also provide effective camouflage through the use of reflection and colouration, as well as possible hydrodynamic advantages. The term ''scale'' derives from the Old French , meaning a shell pod or husk. Scales vary enormously in size, shape, structure, and extent, ranging from strong and rigid armour plates in fishes such as shrimpfishes and boxfishes, to microscopic or absent in fishes such as eels and anglerfishes. The morphology of a scale can be used to identify the species of fish it came from. Scales originated within the jawless ostracoderms, ancestors to all jawed fishes today. Most bony fishes are covered with the cycloid scales of salmon and carp, or the ctenoid scales of perch, or the ganoid scales of sturgeons and gars. Cartilaginous fishes (sharks and rays) are covered with placoid scales. Some species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catfish
Catfish (or catfishes; order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, the Mekong giant catfish from Southeast Asia, the wels catfish of Eurasia, and the piraíba of South America, to detritivores (species that eat dead material on the bottom), and even to a tiny parasitic species commonly called the candiru, ''Vandellia cirrhosa''. Neither the armour-plated types nor the naked types have scales. Despite their name, not all catfish have prominent barbels or "whiskers". Members of the Siluriformes order are defined by features of the skull and swimbladder. Catfish are of considerable commercial importance; many of the larger species are farmed or fished for food. Many of the smaller species, particularly the genus ''Corydoras'', are important in the aquarium hobby. Many catfish are nocturnal, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indoreonectes Evezardi
''Indoreonectes evezardi'' is a species of ray-finned fish in the family Nemacheilidae. Earlier it was known as ''Nemacheilus evezardi'' described by Day (1878) captured from a river stream near Pune. It is endemic to India, found in the Western Ghats and the Satpuras. Most populations are found in normal streams, but two distinct cave-adapted forms exist in Kotumsar Cave. Etymology The fish is named in honor of Col. George C. Evezard (1826-1901), of the Bombay Staff Corps, who helped in procuring the type specimen.http://www.etyfish.com Divergence of cave populations Due to lack of light and limited source of energy input (food) the cave populations of ''Indoreonectes evezardi'' are either found in albinic form with very regressed eyes or with very limited pigmentation and small eyes while compared to its epigean counterparts. Due to subterranean mode of life the complete physiological activities of the cave forms get limited and/or alterehttps://www.researchgate.net/publi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oman Garra
''Garra barreimiae'', the Oman garra, is a species of ray-finned fish in the family Cyprinidae. It is found in the mountains of northern Oman and in the United Arab Emirates. Most populations inhabit wadis, streams, pools and springs, but one population which lives in a cave system, is known as Omani blind cave fish, and has lost its sight and pigmentation. The only other cave fish in the Arabian Peninsula is the Tawi Atair garra (''G. dunsirei''), but it has normal eyes.Romero, A., editor (2001). The Biology of Hypogean Fishes, p. 17. Developments in Environmental Biology of Fishes. Taxonomy The Oman garra was first described in 1956 by the American zoologist Henry Weed Fowler and the Israeli zoologist Heinz Steinitz as ''Garra barreimiae''. The following subspecies are recognised: * ''G. b. barreimiae'' Fowler & Steinitz, 1956 * ''G. b. gallagheri'' Krupp, 1988 * ''G. b. shawkahensis'' Banister & Clarke, 1977 * ''G. b. wurayahi'' Khalaf, 2009 The blind cave form has been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortfin Molly
''Poecilia mexicana'', commonly known as the shortfin molly or Atlantic molly, is a species of poeciliid fish native to fresh and brackish water in Mexico and Guatemala. One population is found in caves and known as the cave molly. Description The maximum standard length of this fish is . It typically grows to a total length . Distribution and habitat The fish lives in tropical freshwater and brackish water habitats. The shortfin molly is considered benthopelagic. It lives in a pH range between 7.0 and 7.5 at temperatures between 22 and 28 degrees Celsius. The species does not migrate. It is an invasive species in the Muddy River of Nevada, USA. Ecology Speciation In two case studies in Cueva del Azufre and Cueva Luna Azufre in Tabasco, Mexico, the Atlantic molly is experiencing speciation. It is occurring between cave and surface populations as well as between habitats of varying sulfur concentrations. Human significance The fishing industry has no interest in harvest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
