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Philometra Otolithi
''Philometra otolithi'' is a species of parasitic nematode of fishes, infecting the gonads of marine perciform fishes off the eastern Indian coast. It was first found in the tigertooth croaker, '' Otolithes ruber''. It is distinguished from its cogenerates by the gubernaculum structure in males, as well as the shape and structure of the females' cephalic and caudal ends, and their oesophagus The esophagus (American English), oesophagus (British English), or œsophagus ( archaic spelling) ( see spelling difference) all ; : ((o)e)(œ)sophagi or ((o)e)(œ)sophaguses), colloquially known also as the food pipe, food tube, or gullet, ....Moravec, Frantisek, and Jayaraman Manoharan. "Gonad-infecting philometrids (Nematoda: Philometridae) including four new species from marine fishes off the eastern coast of India." Folia Parasitologica 60.2 (2013): 105. References Further reading *Moravec, František, Maryam Khosheghbal, and Jamileh Pazooki. "Dichelyne (Dichelyne) spinigerus s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
František Moravec (parasitologist)
František Moravec (born 1 January 1939) is a Czech parasitologist who specialises on the Nematodes, especially the nematodes fish parasites, parasites of fishes. His research is mainly in the field of taxonomy (biology), taxonomy of the Nematoda. Education and career Moravec was born on 1 January 1939 in Velká Bystřice. He was in high school in Olomouc then was a student in the Masaryk University in Brno, Czech Republic (at that time Czechoslovakia). For his Masters in 1962, he studied the parasitic worms of reptiles of Czechoslovakia. After graduation, he worked at the Institute of Parasitology of the Czech Academy of Sciences in České Budějovice, and in 1970 completed his thesis on nematodes parasites in fish. He is a world authority on Nematodes, especially their systematics and biology. Research Among the most important works by Moravec, Tomáš Scholz mentions his revision of the genera ''Rhabdochona'' and ''Anguillicola'', and also his clarification of the family Capi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...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] |
Nematode
The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (helminths) are the cause of soil-transmitted helminthiases. They are classified along with arthropods, tardigrades and other moulting animals in the clade Ecdysozoa. Unlike the flatworms, nematodes have a tubular digestive system, with openings at both ends. Like tardigrades, they have a reduced number of Hox genes, but their sister phylum Nematomorpha has kept the ancestral protostome Hox genotype, which shows that the reduction has occurred within the nematode phylum. Nematode species can be difficult to distinguish from one another. Consequently, estimates of the number of nematode species are uncertain. A 2013 survey of animal biodiversity suggested there are over 25,000. Estimates of the total number of extant species are su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonad
A gonad, sex gland, or reproductive gland is a Heterocrine gland, mixed gland and sex organ that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, produces sperm in the form of Spermatozoon, spermatozoa. The female gonad, the ovary, produces egg cells. Both of these gametes are haploid cells. Some hermaphroditic animals (and some humanssee Ovotesticular syndrome) have a type of gonad called an ovotestis. Evolution It is hard to find a common origin for gonads, but gonads most likely evolved independently several times. Regulation The gonads are controlled by luteinizing hormone (LH) and follicle-stimulating hormone (FSH), produced and secreted by gonadotropic cell, gonadotropes or gonadotrophins in the anterior pituitary gland. This secretion is regulated by gonadotropin-releasing hormone (GnRH) produced in the hypothalamus. Development The gonads develop f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perciform
Perciformes (), also called the Acanthopteri, is an order or superorder of ray-finned fish in the clade Percomorpha. ''Perciformes'' means "perch-like". Among the well-known members of this group are perches and darters (Percidae), and also sea basses and groupers (Serranidae). This order contains many familiar freshwater temperate and tropical marine fish groups, but also extremophiles that have successfully colonized both the North and South Poles, as well as the deepest depths of the ocean. Taxonomy Formerly, this group was thought to be even more diverse than it is thought to be now, containing about 41% of all bony fish (about 10,000 species) and about 160 families, which is the most of any order within the vertebrates. However, many of these other families have since been reclassified within their own orders within the clade Percomorpha, significantly reducing the size of the group. In contrast to this splitting, other groups formerly considered distinct, such as the Sco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otolithes Ruber
''Otolithes ruber'', commonly known as the tigertooth croaker, silver teraglin, wiretooth, snapper kob, snapper salmon, Yankee whiting or Yankee salmon is a species of marine ray-finned fish belonging to the Family (biology), family Sciaenidae, the drums and croakers. This species is found in the Indo-Pacific region. Taxonomy ''Otolithes ruber'' was first formally Species description, described in 1801 as ''Johnius ruber'' by the German naturalists Marcus Elieser Bloch and Johann Gottlob Theaenus Schneider with the "Indian Ocean" given as its Type locality (biology), type locality. In 1817 Lorenz Oken proposed the new genus ''Otolithes'' for this species and in 1863 Theodore Gill designated ''Johnius ruber'' as the type species of the genus. The genus ''Otolithes'' is included in the subfamily Otolithinae by some workers, but the 5th edition of ''Fishes of the World'' does not recognise subfamilies within the Sciaenidae, which it places in the Order (biology), order Acanthuriform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gubernaculum
The paired gubernacula (from Ancient Greek κυβερνάω = pilot, steer), also called the caudal genital ligament, are embryonic structures which begin as undifferentiated mesenchyme attaching to the caudal end of the gonads (testicles in males and ovaries in females). Structure The gubernaculum is present only during the development of the reproductive system. It is later replaced by distinct vestiges in males and females. The gubernaculum arises in the upper abdomen from the lower end of the gonadal ridge and helps guide the testis in its descent to the inguinal region. Males * The upper part of the gubernaculum degenerates. * The lower part persists as the gubernaculum testis (" scrotal ligament"). This ligament secures the testis to the most inferior portion of the scrotum, tethering it in place and limiting the degree to which the testis can move within the scrotum. * Cryptorchidism (undescended testes) are observed in ''INSL3''-null male mice. This implicates INSL ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oesophagus
The esophagus (American English), oesophagus (British English), or œsophagus ( archaic spelling) ( see spelling difference) all ; : ((o)e)(œ)sophagi or ((o)e)(œ)sophaguses), colloquially known also as the food pipe, food tube, or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about long in adults, that travels behind the trachea and heart, passes through the diaphragm, and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word ''esophagus'' is from Ancient Greek οἰσοφάγος (oisophágos), from οἴσω (oísō), future form of φέρω (phérō, "I carry") + ἔφαγον (éphagon, "I ate"). The wall of the esophagus from the lumen outwards consists of mucosa, submucosa (connective tissue), layers of muscle fibers between lay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camallanida
The Camallanida are an order of nematodes. They are parasites of terrestrial and aquatic vertebrates. They also use copepods as obligatory secondary hosts. They are sometimes included in the Spirurida as a suborder Camallanina. Description Amphid apertures of Camallaninas are pore or slit-like. Camallaninas have posterior phasmids. The excretory system of a Camallanina is tubular. Cuticles of Camallaninas are striated in two to four layers. Lateral field is present. Camallaninas have three esophageal glands. Their esophageal structure varies. Sensory papillae of Camallaninas are cephalic. Notable species and genera *''Dracunculus medinensis ''Dracunculus medinensis'' (Guinea worm, dragon worm, fiery serpent) is a nematode that causes dracunculiasis, also known as Guinea worm disease. The disease is caused by the female which, at around in length, is among the longest nematodes ...'' (human as final host) and '' Anguillicola crassus'' (eels as final host) are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Nematodes Of Fish
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] |
