|
Daphnia
''Daphnia'' is a genus of small planktonic crustaceans, in length. ''Daphnia'' are members of the order Anomopoda, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembles the movements of fleas. ''Daphnia'' spp. live in various aquatic environments ranging from acidic swamps to freshwater lakes and ponds. The two most commonly found species of ''Daphnia'' are '' D. pulex'' (small and most common) and '' D. magna'' (large). They are often associated with a related genus in the order Cladocera: ''Moina'', which is in the Moinidae family instead of the Daphniidae, and is much smaller than ''D. pulex'' (roughly half the maximum length). Appearance and characteristics The body of a ''Daphnia'' species is usually long, and is divided into segments, although this division is not visible. The head is fused, and is generally bent down towards the body with a visible notch separating the two. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnia (Daphnia)
''Daphnia'' is one of the three subgenera of the genus ''Daphnia'', the others being '' Australodaphnia'' and '' Ctenodaphnia''. Species *'' Daphnia ambigua'' Scourfield, 1947 *'' Daphnia arenata'' Hebert, 1995 *'' Daphnia catawba'' Coker, 1926 *'' Daphnia cavicervix'' Ekman, 1900 *'' Daphnia cheraphila'' Hebert & Finston, 1996 *'' Daphnia commutata'' Ekman, 1900 *'' Daphnia cristata'' Sars, 1862 *'' Daphnia cucullata'' Sars, 1862 *'' Daphnia curvirostris'' Eylmann, 1887 *'' Daphnia dentifera'' Forbes, 1893 *'' Daphnia dubia'' Herrick, 1883 *'' Daphnia galeata'' Sars, 1864 *'' Daphnia gessneri'' Herbst, 1967 *'' Daphnia hyalina'' Leydig, 1860 *'' Daphnia lacustris'' Sars, 1862 *'' Daphnia laevis'' Birge, 1879 *'' Daphnia latispina'' Kořínek & Hebert, 1996 *'' Daphnia longiremis'' Sars, 1862 *'' Daphnia longispina'' (O. F. Müller, 1776) *'' Daphnia lumholtzi'' Sars, 1885 *'' Daphnia marcahuasensis'' (Valdivia Villar & Burger, 1989) *'' Daphnia melanica'' Hebert, 1995 *'' Daphni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnia Heartbeat
''Daphnia'' is a genus of small planktonic crustaceans, in length. ''Daphnia'' are members of the order Anomopoda, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembles the movements of fleas. ''Daphnia'' spp. live in various aquatic environments ranging from acidic swamps to freshwater lakes and ponds. The two most commonly found species of ''Daphnia'' are '' D. pulex'' (small and most common) and '' D. magna'' (large). They are often associated with a related genus in the order Cladocera: ''Moina'', which is in the Moinidae family instead of the Daphniidae, and is much smaller than ''D. pulex'' (roughly half the maximum length). Appearance and characteristics The body of a ''Daphnia'' species is usually long, and is divided into segments, although this division is not visible. The head is fused, and is generally bent down towards the body with a visible notch separating the two. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnia Magna
''Daphnia magna'' is a small planktonic crustacean (adult length 1.5–5.0 mm) that belongs to the subclass Phyllopoda. Description ''D. magna'' is a typical water flea of the genus ''Daphnia''. The females reach up to 5 mm in size, the males about 2 mm, thus they are among the largest species in the genus. The body is protected by a translucent carapace made of chitin, a transparent polysaccharide. It has a ventral opening and five pairs of thoracic limbs, used to help the filtering process. Spike rows run along the back of the carapace. The intestine is hook-shaped and has two digestive ceca. The head has two antennae and a large compound eye. Adult females can be distinguished from those of otherwise similar species such as '' D. pulex'' by the absence of a comb on the abdominal claw and the presence of two distinct combs on the abdomen. The males are smaller than the females and have larger first antennas, a diagnostic feature that distinguishes them from s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnia Pulex
''Daphnia pulex'' is the most common species of water flea. It has a cosmopolitan distribution: the species is found throughout the Americas, Europe, and Australia. It is a model species, and was the first crustacean to have its genome sequenced. Description ''D. pulex'' is an arthropod whose body segments are difficult to distinguish. It can only be recognised by its appendages (only ever one pair per segment), and by studying its internal anatomy. The head is distinct and is made up of six segments, which are fused together even as an embryo. It bears the mouthparts, and two pairs of antennae, the second pair of which is enlarged into powerful organs used for swimming. No clear division is seen between the thorax and abdomen, which collectively bear five pairs of appendages. The shell surrounding the animal extends posteriorly into a spine. Like most other ''Daphnia'' species, ''D. pulex'' reproduces by cyclical parthenogenesis, alternating between sexual and asexual rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Flea
The Diplostraca or Cladocera, commonly known as water fleas, are a superorder of small crustaceans that feed on microscopic chunks of organic matter (excluding some predatory forms). Over 1000 species have been recognised so far, with many more undescribed. The oldest fossils of diplostracans date to the Jurassic, though their modern morphology suggests that they originated substantially earlier, during the Paleozoic. Some have also adapted to a life in the ocean, the only members of Branchiopoda to do so, even if several anostracans live in hypersaline lakes. Most are long, with a down-turned head with a single median compound eye, and a carapace covering the apparently unsegmented thorax and abdomen. Most species show cyclical parthenogenesis, where asexual reproduction is occasionally supplemented by sexual reproduction, which produces resting eggs that allow the species to survive harsh conditions and disperse to distant habitats. Description They are mostly long, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnia Occidentalis
''Daphnia occidentalis'' is a species of crustacean in the family Daphniidae. It is endemic to Australia Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by ..., and is the only species in the subgenus ''Australodaphnia''. References Cladocera Vulnerable fauna of Australia Freshwater crustaceans of Australia Taxonomy articles created by Polbot Crustaceans described in 1986 {{Branchiopoda-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphniidae
Daphniidae is a family of water fleas in the order Anomopoda. Description Members of the family Daphniidae differ from other, similar diplostracans, such as the Macrotrichidae and Moinidae, in that the antennae of females are short and immobile. Ecology The feeding mechanism of the members of the family Daphniidae differs from that of the Macrotrichidae in allowing the animals to engage in filter feeding, rather than having to scrape food from a surface. They have evolved to fill a number of different ecological niches. ''Scapholeberis'' and '' Megafenestra'' contain species adapted to living around the surface film; '' Simocephalus'' species cling to objects while filter feeding; others have developed a pelagic lifestyle. Taxonomy The family Daphniidae contains 121 species in five genera: *''Ceriodaphnia'' Dana, 1853 *''Daphnia'' O. F. Müller, 1785 *'' Megafenestra'' Dumont & Pensaert, 1983 *''Scapholeberis'' Schoedler, 1858 *'' Simocephalus'' Schoedler, 1858 The members of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomopoda
Anomopoda is an order of the superorder Diplostraca. These crustaceans, a type of water flea, are members of the class Branchiopoda. The Anomopoda typically have five pairs of thoracic limbs, but sometimes have six pairs. The head of the Anomopoda lacks a clear separation from the trunk and the posterior, while the abdomen area gradually merges with the anterior of the trunk. See also *''Daphnia ''Daphnia'' is a genus of small planktonic crustaceans, in length. ''Daphnia'' are members of the order Anomopoda, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembl ...'' - water fleas *'' Rhynchochydorus'' References Cladocera Freshwater crustaceans Arthropod suborders {{Branchiopoda-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moina
''Moina'' is a genus of crustaceans within the family Moinidae. The genus was first described by W. Baird in 1850. They are referred to as water fleas, but are related to the much larger ''Daphnia magna'' and the larger ''Daphnia pulex''. This genus demonstrates the ability to survive in waters containing low oxygen levels, high salinity, and other impurities, including salt pans, and commonly eutrophication. An example of such an extreme habitat is the highly saline Makgadikgadi Pans of Botswana, which supports prolific numbers of '' Moina belli''. The ''Moina'' are known to be found in various types of bodies of water in Eurasia where new found research indicates that there is an increased presence of biodiversity in regions of Northern Eurasia, Japan and China. There is an increase of new phylogroups found in Northern Eurasia, an increase of 4 new ''Moina'' species in Japan and an increase of five new lineages in China. Species ''Moina'' contains these species: * '' M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saltation (gait)
Terrestrial locomotion has evolved as animals adapted from aquatic to terrestrial environments. Locomotion on land raises different problems than that in water, with reduced friction being replaced by the increased effects of gravity. As viewed from evolutionary taxonomy, there are three basic forms of animal locomotion in the terrestrial environment: * legged – moving by using appendages * limbless locomotion – moving without legs, primarily using the body itself as a propulsive structure. *rolling – rotating the body over the substrate Some terrains and terrestrial surfaces permit or demand alternative locomotive styles. A sliding component to locomotion becomes possible on slippery surfaces (such as ice and snow), where location is aided by potential energy, or on loose surfaces (such as sand or scree), where friction is low but purchase (traction) is difficult. Humans, especially, have adapted to sliding over terrestrial snowpack and terrestrial ice by means of ice s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
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 fol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circulatory System
The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek ''kardia'' meaning ''heart'', and from Latin ''vascula'' meaning ''vessels''). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms ''cardiovascular system'' and ''vascular system'' interchangeably with the ''circulatory system''. The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The circulatory system is closed in vertebrates, which means that the blood never leaves the network of blood vessels. Some invertebrates such as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
