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Georgia Blind Salamander
The Georgia blind salamander (''Eurycea wallacei'') is a species of salamander in the family Plethodontidae (the "lungless salamanders"). It is endemic to the south-eastern United States where its natural habitats are inland karsts, caves and subterranean habitats (other than caves). It is listed as "Endangered" by the IUCN and is threatened by habitat loss. Taxonomy The Georgia blind salamander was originally described as a member of the monotypic genus '' Haideotriton'', but was later placed in the genus ''Eurycea''. Distribution The Georgia blind salamander is found in underground habitats in the Southeastern United States. Its precise distribution is unknown, however the first specimen to be examined scientifically was discovered in 1939 in water pumped from a deep well in Albany, Georgia. The only other locality in Georgia from which it is known is the Climax Cave, near Climax, Georgia, in Decatur County. The salamander is also known from at least eight locations near Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salamander
Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All ten extant salamander families are grouped together under the order Urodela. Salamander diversity is highest in eastern North America, especially in the Appalachian Mountains; most species are found in the Holarctic realm, with some species present in the Neotropical realm. Salamanders rarely have more than four toes on their front legs and five on their rear legs, but some species have fewer digits and others lack hind limbs. Their permeable skin usually makes them reliant on habitats in or near water or other cool, damp places. Some salamander species are fully aquatic throughout their lives, some take to the water intermittently, and others are entirely terrestrial as adults. This group of amphibians is capable of regenerating lost lim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ostracod
Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typically around in size, but varying from in the case of ''Gigantocypris''. Their bodies are flattened from side to side and protected by a bivalve-like, chitinous or calcareous valve or "shell". The hinge of the two valves is in the upper (dorsal) region of the body. Ostracods are grouped together based on gross morphology. While early work indicated the group may not be monophyletic and early molecular phylogeny was ambiguous on this front, recent combined analyses of molecular and morphological data found support for monophyly in analyses with broadest taxon sampling. Ecologically, marine ostracods can be part of the zooplankton or (most commonly) are part of the benthos, living on or inside the upper layer of the sea floor. While Myodoc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave Salamander
A cave salamander is a type of salamander that primarily or exclusively inhabits caves, a group that includes several species. Some of these animals have developed special, even extreme, adaptations to their subterranean environments. Some species have only rudimentary (or even absent) eyes (''blind salamanders''). Others lack pigmentation, rendering them a pale yellowish or pinkish color (e.g., ''Eurycea rathbuni''). With the notable exception of ''Proteus anguinus'', all "cave salamanders" are members of the family Plethodontidae ("lungless salamanders"). History The first dedicated scientific study of a cave animal was focused upon a cave salamander, ''Proteus anguinus''. It was originally identified as a "dragon's larva" by Johann Weikhard von Valvasor in 1689. Later, the Austrian naturalist Joseph Nicolaus Lorenz described it scientifically in 1768. Another early scientific description of a cave salamander was undertaken by Constantine Samuel Rafinesque in 1822 while he w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Table
The water table is the upper surface of the zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with water. It can also be simply explained as the depth below which the ground is saturated. The water table is the surface where the water pressure head is equal to the atmospheric pressure (where gauge pressure = 0). It may be visualized as the "surface" of the subsurface materials that are saturated with groundwater in a given vicinity. The groundwater may be from precipitation or from groundwater flowing into the aquifer. In areas with sufficient precipitation, water infiltrates through pore spaces in the soil, passing through the unsaturated zone. At increasing depths, water fills in more of the pore spaces in the soils, until a zone of saturation is reached. Below the water table, in the phreatic zone (zone of saturation), layers of permeable rock that yield groundwater are called aquifers. In less permeable soils, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Florida Caverns State Park
Florida Caverns State Park is a state park of Florida in the United States, part of the Florida State Parks system. It is located in the Florida Panhandle near Marianna. It is the only Florida state park with air-filled caves accessible to the public.Florida Caverns State Park, Introduction. Florida State Parks. The in the park have s, and |
Redeye Chub
Redeye chub (''Notropis harperi'') is a species of cyprinid 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 verte ... fish native to freshwaters of southeastern North America. References * Robert Jay Goldstein, Rodney W. Harper, Richard Edwards: ''American Aquarium Fishes''. Texas A&M University Press 2000, , p. 101 () * Notropis Fish described in 1941 {{Leuciscinae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brown Bullhead
The brown bullhead (''Ameiurus nebulosus'') is a fish of the family Ictaluridae that is widely distributed in North America. It is a species of bullhead catfish and is similar to the black bullhead (''Ameiurus melas'') and yellow bullhead (''Ameiurus natalis''). It was originally described as ''Pimelodus nebulosus'' by Charles Alexandre Lesueur in 1819, and is also referred to as ''Ictalurus nebulosus''. The brown bullhead is also widely known as the "mud pout", "horned pout", "hornpout", or simply "mud cat", a name also used with the other bullhead species. The brown bullhead is important as a clan symbol of the Ojibwe people. In their tradition, the bullhead or is one of six beings that came out of the sea to form the original clans. Appearance The brown bullhead grows to be approximately in length and is a darker brown-green dorsally, growing lighter green and yellow towards the ventral surface. The belly is off-white or cream, and the fish has no scales. Additionally, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Eel
The American eel (''Anguilla rostrata'') is a facultative catadromous fish found on the eastern coast of North America. Freshwater eels are fish belonging to the elopomorph superorder, a group of phylogenetically ancient teleosts. The American eel has a slender, snake-like body that is covered with a mucus layer, which makes the eel appear to be naked and slimy despite the presence of minute scales. A long dorsal fin runs from the middle of the back and is continuous with a similar ventral fin. Pelvic fins are absent, and relatively small pectoral fins can be found near the midline, followed by the head and gill covers. Variations exist in coloration, from olive green, brown shading to greenish-yellow and light gray or white on the belly. Eels from clear water are often lighter than those from dark, tannic acid streams. The eel lives in fresh water and estuaries and only leaves these habitats to enter the Atlantic Ocean to make its spawning migration to the Sargasso Sea. Spa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dougherty Plain Blind Crayfish
''Cambarus cryptodytes'', the Dougherty Plain cave crayfish or Apalachicola cave crayfish, is a small, freshwater crayfish endemic to Florida and Georgia in the United States. It is an underground species known only from waters associated with the Floridan aquifer. Description The Dougherty Plain cave crayfish grows to a length of about with antennae twice this length. It is a colourless species with unpigmented eyes, segmented cephalothorax and abdomen, a pair of slender chelae (claws) with a row or two of tubercles and long slender appendages. The rostrum is long and unadorned with tubercles or spines. Distribution The Dougherty Plain cave crayfish is known from springs, wells and cave systems in the karst limestone region of Dougherty Plain in the Southeastern United States. It has been found in Dougherty County and Decatur County in Georgia and Jackson County and Washington County in Florida. It is likely also to be present in Mitchell County and Baker County, Geor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insects, fish, amphibians, mollusks, crustaceans, cnidarians, echinoderms, and tunicates undergo metamorphosis, which is often accompanied by a change of nutrition source or behavior. Animals can be divided into species that undergo complete metamorphosis (" holometaboly"), incomplete metamorphosis ("hemimetaboly"), or no metamorphosis (" ametaboly"). Scientific usage of the term is technically precise, and it is not applied to general aspects of cell growth, including rapid growth spurts. Generally organisms with a larva stage undergo metamorphosis, and during metamorphosis the organism loses larval characteristics. References to "metamorphosis" in mammals are imprecise and only colloquial, but historically idealist ideas of transformation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoteny
Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the physiological, or somatic, development of an organism, typically an animal. Neoteny is found in modern humans compared to other primates. In progenesis or paedogenesis, sexual development is accelerated. Both neoteny and progenesis result in paedomorphism (as having the form typical of children) or paedomorphosis (changing towards forms typical of children), a type of heterochrony. It is the retention in adults of traits previously seen only in the young. Such retention is important in evolutionary biology, domestication and evolutionary developmental biology. Some authors define paedomorphism as the retention of larval traits, as seen in salamanders.Schell, S. C. ''Handbook of Trematodes of North America North of Mexico'', 1985, pg. 22 History and etymology The origins of the concept of neoteny have been traced to the Bible (as argued by Ashley Monta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
