Trematoda is a class within the phylum Platyhelminthes. It includes two groups of parasitic flatworms, known as flukes.
Digenea is a class of trematodes in the Platyhelminthes phylum, consisting of parasitic flatworms with a syncytial tegument and, usually, two suckers, one ventral and one oral. Adults commonly live within the digestive tract, but occur throughout the organ systems of all classes of vertebrates. Once thought to be related to the Monogenea, it is now recognised that they are closest to the Aspidogastrea and that the Monogenea are more closely allied with the Cestoda. Around 6,000 species have been described to date.
Trematodes are parasitic flatworms of the class Trematoda, specifically parasitic flukes with two suckers: one ventral and the other oral. Trematodes are covered by a tegument, that protects the organism from the environment by providing secretory and absorptive functions.
Paragonimus westermani is the major species of lung fluke that infects humans, causing paragonimiasis. The species sometimes is called the Japanese lung fluke or oriental lung fluke. Human infections are most common in eastern Asia and in South America. Paragonimus westermani was discovered when two Bengal tigers died of paragonimiasis in zoos in Europe in 1878. Several years later, infections in humans were recognised in Formosa.
Echinostoma is a genus of trematodes (flukes), which can infect both humans and other animals. These intestinal flukes have a three-host life cycle with snails or aquatic organisms as intermediate hosts, and a variety of animals, including humans, as their definitive hosts.
Paragonimiasis is a food-borne parasitic infection caused by the lung fluke, most commonly Paragonimus westermani. It infects an estimated 22 million people yearly worldwide. It is particularly common in East Asia. More than 30 species of trematodes (flukes) of the genus Paragonimus have been reported; among the more than 10 species reported to infect humans, and only 8 bringing about infections in humans, the most common is P. westermani, the oriental lung fluke.
Dicrocoelium dendriticum, the lancet liver fluke, is a parasite fluke that tends to live in cattle or other grazing mammals.
Metagonimoides oregonensis is a trematode, or fluke worm, in the family Heterophyidae. This North American parasite is found primarily in the intestines of raccoons, American minks, frogs in the genus Rana, and freshwater snails in the genus Goniobasis. It was first described in 1931 by E. W. Price. The parasite has a large distribution, from Oregon to North Carolina. Adult flukes vary in host range and morphology dependent on the geographical location. This results in different life cycles, as well as intermediate hosts, across the United States. On the west coast, the intermediate host is freshwater snails (Goniobasis), while on the east coast the intermediate host is salamanders (Desmognathus). The parasites on the west coast are generally much larger than on the east coast. For example, the pharynx as well as the body of the parasite are distinctly larger in Oregon than in North Carolina. The reverse pattern is observed on the east coast for uterine eggs, which are larger on the west coast. In snails, there is also a higher rate of infection in female snails than in males. Research on the life history traits of the parasites have been performed with hamsters and frogs as model species.
Leucochloridium variae, the brown-banded broodsac, is a species of trematode whose life cycle involves the alternate parasitic invasion of certain species of snail and bird. While there is no external evidence of the worm's existence within the bird host, the invasion of the snail host involves the grotesque swelling of one or both of the snail's eye stalks. This invasion does not cause the snail's death.
Fasciolopsis is a genus of trematodes. They are also known as the intestinal flukes.
Echinostoma revolutum is a trematode that can be parasitic in humans. It causes the disease echinostomiasis.
Echinostoma hortense is an intestinal fluke of the class Trematoda, which has been found to infect humans in East Asian countries such as Korea, China, and Japan. This parasite resides in the intestines of birds, rats and other mammals such as humans. While human infections are very rare in other regions of the world, East Asian countries have reported human infections up to about 24% of the population in some endemic sub-regions. E. hortense infections are zoonotic infections, which occurs from eating raw or undercooked freshwater fish. The primary disease associated with an E. hortense infection is called echinostomiasis, which is a general name given to diseases caused by Trematodes of the genus Echinostoma.
Telogaster opisthorchis is an endoparasite in the class Trematoda within the phylum Platyhelminthes. This fluke is known for causing tumor like malformations in fishes by attaching onto its spinal region in the metacercariae form. Malformations cause fish to become more susceptible to fish eating predators allowing T. opisthorchis to continue with its lifecycle.
Clinostomum marginatum is a species of parasitic fluke. It is commonly called the "yellow grub". It is found in many freshwater fish in North America, and no fish so far is immune to this parasite. It is also found in frogs. Clinostomum marginatum can also be found in the mouth of aquatic birds such as herons and egrets. They are commonly present in the esophagus of fish-eating birds and reptiles. Eggs of these trematodes are shed in the feces of aquatic birds and released into water. Aquatic birds become hosts of this parasite by ingesting infected freshwater fish. The metacercariae are found right beneath the skin or in the muscles of host fish.
Megalodiscus temperatus is a Digenean in the phylum Platyhelminthes. This parasite belongs to the Diplodiscidae family and is a common parasite located in the urinary bladder and rectum of frogs. The primary host is frogs and the intermediate hosts of Megalodiscus temeperatus are freshwater snails in the genus Helisoma.
Philophthalmus lacrimosus is a species of trematodes in the family Philophthalmidae.
Paramphistomum cervi, the type species of Paramphistomum, is a parasitic flat worm belonging to the class Trematoda. It is a tiny fluke mostly parasitising livestock ruminants, as well as some wild mammals. Uniquely, unlike most parasites, the adult worms are relatively harmless, but it is the developing juveniles that cause serious disease called paramphistomiasis, especially in cattle and sheep. Its symptoms include profuse diarrhoea, anaemia, lethargy, and often result in death if untreated.
Paramphistomum is a genus of parasitic flatworms belonging to the digenetic trematodes. It includes flukes which are mostly parasitising livestock ruminants, as well as some wild mammals. They are responsible for the serious disease called paramphistomiasis, also known as amphistomosis, especially in cattle and sheep. Its symptoms include profuse diarrhoea, anaemia, lethargy, and often result in death if untreated. They are found throughout the world, and most abundantly in livestock farming regions such as Australia, Asia, Africa, Eastern Europe, and Russia.
Brachylaimidae is a family of parasitic flukes in the sub-class Digenea. Adults are usually found within the digestive tracts and other organs of mammals or birds and have a complex three-stage life cycle.
Metagonimus yokogawai is a species of a trematode, or fluke worm, in the family Heterophyidae.
