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Myxosporea
Myxosporea is a class of microscopic animals, all of whom are parasites. They belong to the Myxozoa clade within Cnidaria. They have a complex life cycle that comprises vegetative forms in two hosts—one an aquatic invertebrate (generally an annelid but sometimes a bryozoan) and the other an ectothermic vertebrate, usually a fish. Each parasitized host releases a different type of spore. The two forms of spore are so different in appearance that until relatively recently they were treated as belonging to different classes within the Myxozoa. Taxonomic status The taxonomy of both actinosporeans and myxosporeans was originally based on spore morphology. In 1994 the phylum Myxozoa was redefined to solve the taxonomic and nomenclatural problems arising from the two-host life cycle of myxozoans. The distinction between the two previously recognised classes Actinosporea and Myxosporea disappeared and the class ''Actinosporea'' was suppressed, becoming a synonym of the class ''Myxosp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myxozoa
Myxozoa (etymology: Greek: μύξα ''myxa'' "slime" or "mucus" + thematic vowel o + ζῷον ''zoon'' "animal") is a subphylum of aquatic cnidarian animals – all obligate parasites. It contains the smallest animals ever known to have lived. Over 2,180 species have been described and some estimates have suggested at least 30,000 undiscovered species. Many have a two-host lifecycle, involving a fish and an annelid worm or a bryozoan. The average size of a myxosporean spore usually ranges from 10 μm to 20 μm, whereas that of a malacosporean (a subclade of the Myxozoa) spore can be up to 2 mm. Myxozoans can live in both freshwater and marine habitats. Myxozoans are highly derived cnidarians that have undergone dramatic evolution from a free swimming, self-sufficient jellyfish-like creature into their current form of obligate parasites composed of very few cells. As myxozoans evolved into microscopic parasites, they lost many genes responsible for multice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceratonova Shasta
''Ceratonova shasta'' (syn. ''Ceratomyxa shasta'') is a myxosporean parasite that infects salmonidae, salmonid fish on the Pacific coast of North America. It was first observed at the Crystal Lake Hatchery, Shasta County, California, Shasta County, California, and has now been reported from Idaho, Oregon, Washington (state), Washington, British Columbia and Alaska. Life history In addition to the fish host, ''C. shasta'' infects a freshwater polychaete worm. Actinosporea, Actinospores are released from the worm, and infect fish, on contact, in the water column. Neither horizontal (fish to fish), nor vertical (fish to egg) transmissions have been documented under laboratory conditions, suggesting that the worm host is necessary for completion of the life cycle. Spores are released back into freshwater system after its fish host dies, however the complete life cycle, host and vector interaction is not fully understood (especially the ecology of the polychaete host). Research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kudoa Septempunctata
''Kudoa septmpunctata'' is a Myxosporea, myxosporean parasite commonly found in raw Olive flounder, olive flounders. The parasite is associated with food poisoning. References Myxosporea {{Parasite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasite
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of life. The entomologist E. O. Wilson characterised parasites' way of feeding as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalvulida
Bivalvulida is an order of myxosporean parasites which contains a number of species which cause economically significant losses to aquaculture and fisheries, such as ''Myxobolus cerebralis'' and ''Ceratomyxa shasta''. The Myxosporean stages of members of the bivalvulida are characterised by their two spore valves (hence the name), which meet in a "suture line" which encircles the spore. They usually contain two polar capsules, but species have been reported which contain either one or four. Taxonomy and systematics The order Bivalvulida is composed of three suborders and thirteen families. *Suborder Platysporina Kudo, 1919Kudo, R. (1919). Studies on Myxosporidia. A synopsis of genera and species of Myxosporidia. ''Illinois Biological Monographs'', 5. **Myxobolidae Thélohan, 1892Thélohan, P. (1892). Observation sur les myxosporidies et essai de classification de ces organismes. ''Bulletin de la Société Philomatique de Paris'', 4, 165–178. *Suborder Sphaeromyxina Lom & Noble, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annelid
The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. The annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion. Most textbooks still use the traditional division into polychaetes (almost all marine), oligochaetes (which include earthworms) and leech-like species. Cladistic research since 1997 has radically changed this scheme, viewing leeches as a sub-group of oligochaetes and oligochaetes as a sub-group of polychaetes. In addition, the Pogonophora, Echiura and Sipuncula, previously regarded as separate phyla, are now regarded as sub-grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multivalvulida
Multivalvulida is an order of myxozoa Myxozoa (etymology: Greek: μύξα ''myxa'' "slime" or "mucus" + thematic vowel o + ζῷον ''zoon'' "animal") is a subphylum of aquatic cnidarian animals – all obligate parasites. It contains the smallest animals ever known to have lived. ...n. Families * Kudoidae * Spinavaculidae * Trilosporidae ReferencesEncyclopedia of Life entry Myxosporea Cnidarian orders {{Myxozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Inquirenda
In biological classification, a ''species inquirenda'' is a species of doubtful identity requiring further investigation. The use of the term in English-language biological literature dates back to at least the early nineteenth century. The term ''taxon inquirendum'' is broader in meaning and refers to an incompletely defined taxon of which the taxonomic validity is uncertain or disputed by different experts or is impossible to identify the taxon. Further characterization is required. Certain species names may be designated unplaced names, which ''Plants of the World Online'' defines as "names that cannot be accepted, nor can they be put into synonymy". Unplaced names may be names which were not validly published, later homonyms which are therefore illegitimate, or species which cannot be accepted because the genus name is not accepted. Species names may remain unplaced if there is no accepted species in a genus in which it can be placed, or if the type material for the species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disease Vector
In epidemiology, a disease vector is any living agent that carries and transmits an infectious pathogen such as a parasite or microbe, to another living organism. Agents regarded as vectors are mostly blood-sucking ( hematophagous) arthropods such as mosquitoes. The first major discovery of a disease vector came from Ronald Ross in 1897, who discovered the malaria pathogen when he dissected the stomach tissue of a mosquito. Arthropods Arthropods form a major group of pathogen vectors with mosquitoes, flies, sand flies, lice, fleas, ticks, and mites transmitting a huge number of pathogens. Many such vectors are haematophagous, which feed on blood at some or all stages of their lives. When the insects and ticks feed on blood, the pathogen enters the blood stream of the host. This can happen in different ways. The '' Anopheles'' mosquito, a vector for malaria, filariasis, and various arthropod-borne-viruses ( arboviruses), inserts its delicate mouthpart under the skin and feeds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, have myocytes and are motility, able to move, can reproduce sexually, and grow from a hollow sphere of Cell (biology), cells, the blastula, during embryonic development. Animals form a clade, meaning that they arose from a single common ancestor. Over 1.5 million extant taxon, living animal species have been species description, described, of which around 1.05 million are insects, over 85,000 are molluscs, and around 65,000 are vertebrates. It has been estimated there are as many as 7.77 million animal species on Earth. Animal body lengths range from to . They have complex ecologies and biological interaction, interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naididae
The Naididae (including the former family Tubificidae) are a family (biology), family of clitellate oligochaete worms like the sludge worm, ''Tubifex tubifex''. They are key components of the benthic communities of many freshwater and ocean, marine ecosystems. In freshwater aquaria they may be referred to as detritus worms. Description These worms can vary in size, from centimeters to millimeters, depending on the subfamily. They are all hermaphroditic and lack a larval stage. Taxonomy Analysis of 18S rDNA sequences revealed that the traditional family Tubificidae is not monophyletic, with the traditionally circumscribed Naididae nested within tubificid taxa. To avoid paraphyly the naidid and tubificid taxa were included in a combined family, which took the name Naididae because it has priority under ''International Code of Zoological Nomenclature'' rules as the senior synonym of Tubificidae. A proposal to the International Commission on Zoological Nomenclature to suppress Naidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmonid
Salmonidae (, ) is a family of ray-finned fish, the only extant member of the suborder Salmonoidei, consisting of 11 extant genera and over 200 species collectively known as "salmonids" or "salmonoids". The family includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), char, graylings, freshwater whitefishes, taimens and lenoks, all coldwater mid-level predatory fish that inhabit the subarctic and cool temperate waters of the Northern Hemisphere. The Atlantic salmon (''Salmo salar''), whose Latin name became that of its genus ''Salmo'', is also the eponym of the family and order names. Salmonids have a relatively primitive appearance among teleost fish, with the pelvic fins being placed far back, and an adipose fin towards the rear of the back. They have slender bodies with rounded scales and forked tail fins, and their mouths contain a single row of sharp teeth. Although the smallest salmonid species is just long for adults, most salm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
