| Hysterothylacium | |
|---|---|
 | |
| Hysterothylacium epinepheli (Yamaguti, 1941) | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Nematoda |
| Class: | Chromadorea |
| Order: | Ascaridida |
| Family: | Raphidascarididae |
| Genus: | Hysterothylacium Ward & Magath, 1917 |
Hysterothylacium is a genus of parasitic roundworms in the family Raphidascarididae. As of 2020 it consists of over 70 species [1] [2] [3] [4] [5] [6] and is considered one of the largest of the ascaridoid genera parasitising fish.
Species in the genus complete their life cycle between predatory teleost fish [7] as their final host and various species of invertebrates and teleost as their intermediate hosts. These parasites are not host specific in the larval stages and infect a broad range of fish species; thus they are widely distributed throughout the aquatic ecosystem and exhibit a global distribution. Hysterothylacium aduncum infection in fish has been associated with mechanical damage to the heart, eye and fish musculature which occurs as a result of parasite larval migration. [8] [9] Catastrophic loss of fish fry due to infection with an unknown species of Hysterothylacium has been reported. [10] Human infection is not common but has been reported in Japan. [11]
Monogeneans, members of the class Monogenea, are a group of ectoparasitic flatworms commonly found on the skin, gills, or fins of fish. They have a direct lifecycle and do not require an intermediate host. Adults are hermaphrodites, meaning they have both male and female reproductive structures.
Anisakis is a genus of parasitic nematodes that have life cycles involving fish and marine mammals. They are infective to humans and cause anisakiasis. People who produce immunoglobulin E in response to this parasite may subsequently have an allergic reaction, including anaphylaxis, after eating fish infected with Anisakis species.
Acanthocheilonema is a genus within the family Onchocercidae which comprises mainly tropical parasitic worms. Cobbold created the genus Acanthocheilonema with only one species, Acanthocheilonema dracunculoides, which was collected from aardwolf in the region of South Africa in the nineteenth century. These parasites have a wide range of mammalian species as hosts, including members of Carnivora, Macroscelidea, Rodentia, Pholidota, Edentata, and Marsupialia. Many species among several genera of filarioids exhibit a high degree of endemicity in studies done on mammalian species in Japan. However, no concrete evidence has confirmed any endemic species in the genus Acanthocheilonema.
Parasitic worms, also known as helminths, are large macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other parasitic worms such as schistosomes reside in blood vessels.
The Anisakidae are a family of intestinal nematodes (roundworms). The larvae of these worms can cause anisakiasis when ingested by humans, in raw or insufficiently cooked fish.
Like humans and other animals, fish suffer from diseases and parasites. Fish defences against disease are specific and non-specific. Non-specific defences include skin and scales, as well as the mucus layer secreted by the epidermis that traps microorganisms and inhibits their growth. If pathogens breach these defences, fish can develop inflammatory responses that increase the flow of blood to infected areas and deliver white blood cells that attempt to destroy the pathogens.
Lethrinus rubrioperculatus,the spotcheek emperor, red-eared emperor, red-ears, red-edged emperor, scarlet-cheek emperor, and spot cheek emperor, is a species of marine ray-finned fish belonging to the family Lethrinidae, the emperors or emperor breams. This species has a wide Indo-Pacific distribution.
Philometra is a genus of nematodes, which are parasites of marine and freshwater fishes. The genus was erected by Oronzio Gabriele Costa in 1845.
Setaria is a genus of parasitic roundworms that infect domesticated mammals such as pigs, camels, cattle and horses. Some species also infect wild mammals such as deer and antelope. The genus consists of about 43 species. Members of the genus are uniquely parasites in the abdominal cavity of the body. They are mostly large-sized roundworms, possessing an elaborate head (cephalic) region that is characterised by spines, presence of four lips, and well-guarded mouth. Little is known about their pathogenic effects, but some are known to affect the nervous system and eye. The larval infective forms are transmitted from one animal to another by the bite of mosquitoes and flies. In addition Setaria marshalli can be transmitted from the womb to new-born calf.
Pseudorhabdosynochus is a genus of monopisthocotylean monogeneans, included in the family Diplectanidae. The type-species of the genus is Pseudorhabdosynochus epinepheli .
Anisakis simplex, known as the herring worm, is a species of nematode in the genus Anisakis. Like other nematodes, it infects and settles in the organs of marine animals, such as salmon, mackerels and squids. It is commonly found in cold marine waters, such as the Pacific Ocean and Atlantic Ocean.
Gadimyxa arctica is a species of parasitic myxozoan. Together with G. atlantica and G. sphaerica, they infect Gadus morhua and Arctogadus glacialis by developing coelozoically in bisporic plasmodia in their urinary systems. These 3 species' spores exhibit two morphological forms: wide and subspherical, being both types bilaterally symmetrical along the suture line. The wide spores have a mean width ranging from 7.5-10μm, respectively, while the subspherical ones range from 5.3-8μm in mean width. The subspherical forms of Gadimyxa are similar to Ortholinea, differing in the development of the spores and in the arrangement of the polar capsules.
Peniculisa is a genus of marine parasitic copepods in the family Pennellidae.
Cucullanus is a genus of parasitic nematodes. The genus includes more than 100 species.
František Moravec is a Czech parasitologist who specialises on the Nematodes, especially the nematodes parasites of fishes. His research is mainly in the field of taxonomy of the Nematoda.
Contracaecum is a genus of parasitic nematodes from the family Anisakidae. These nematodes are parasites of warm-blooded, fish eating animals, i.e. mammals and birds, as sexually mature adults. The eggs and the successive stages of their larvae use invertebrates and increasing size classes of fishes as intermediate hosts. It is the only genus in the family Anisakidae which can infect terrestrial, marine and freshwater animals.
Terranova is a genus of parasitic nematodes. Species from this genus are known to parasitise sharks, rays, sawfishes, teleosts and crocodilians.
Pseudoterranova is a genus within the family Anisakidae of parasitic nematodes with an aquatic life cycle. The lifecycle of Pseudoterranova spp. involves marine mammals, pinnipeds, as definitive hosts, planktonic or benthic crustaceans as intermediate hosts and fish which act as second intermediate or paratenic hosts. In some regions, the rise in seal numbers has prefaced a significant increase in fish infected with P. decipiens which is of concern for fish health. Infection with Pseudoterranova may affect the health and swimming ability of the fish host and is therefore of concern for the survival of wild caught and farmed species. Species belonging to this genus have been demonstrated to cause illness of varying exigency in humans if raw or under cooked infected fish is consumed. Cases of human infection have been reported from consuming partially cooked fish infected with Pseudoterranova decipiens, Pseudoterranova cattani and Pseudoterranova azarasi. The propensity of P. decipiens to encyst in the edible portion of fish musculature may make this parasite a considerable threat to human health in undercooked fish.
Raphidascarididae is a family of roundworms in the order Ascaridida. It encompasses nine genera and over 190 species.