Trematoda is a class of flatworms known as flukes or trematodes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive host, where the flukes sexually reproduce, is a vertebrate. Infection by trematodes can cause disease in all five traditional vertebrate classes: mammals, birds, amphibians, reptiles, and fish.
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.
Microphallus is a genus of parasitic trematodes (flukes) in the family Microphallidae. The Greek name means "tiny penis".
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.
Ribeiroia is a genus of trematode parasites that sequentially infect freshwater snails in the family Planorbidae as first intermediate hosts, fish and larval amphibians as second intermediate hosts, and birds and mammals as definitive hosts. In North America, infection by Ribeiroia has been linked to amphibians with limb malformations. The connection between parasitic infection and limb malformations has generated questions about (a) whether parasite-induced malformations in amphibians are increasing, and (b) the consequences of such abnormalities for amphibian population conservation.
Potamididae, common name potamidids are a family of small to large brackish water snails that live on mud flats, mangroves and similar habitats. They are amphibious gastropod molluscs in the superfamily Cerithioidea.
Euhaplorchis californiensis is a trophically transmitted parasite (TTP) that lives in the salt-water marshes of Southern California, United States. It lives in three hosts: shorebirds, horn snails, and killifish. As with many TTPs, E. californiensis modifies the behavior of the host to increase the likelihood of transmission to its next host.
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.
Nanophyetus salmincola is a food-borne intestinal trematode parasite prevalent on the Pacific Northwest coast. The species may be the most common trematode endemic to the United States.
Cerithidea is a genus of medium-sized sea snails or mud snails, marine gastropod mollusks in the family Potamididae, the horn snails.
Parasitic castration is the strategy, by a parasite, of blocking reproduction by its host, completely or in part, to its own benefit. This is one of six major strategies within parasitism.
Heterophyes heterophyes, or the intestinal fish fluke, was discovered by Theodor Maximaillian Bilharz in 1851. This parasite was found during an autopsy of an Egyptian mummy. H. heterophyes is found in the Middle East, West Europe and Africa. They use different species to complete their complex lifestyle. Humans and other mammals are the definitive host, first intermediate host are snails, and second intermediate are fish. Mammals that come in contact with the parasite are dogs, humans, and cats. Snails that are affected by this parasite are the Cerithideopsilla conica. Fish that come in contact with this parasite are Mugil cephalus, Tilapia milotica, Aphanius fasciatus, and Acanthgobius sp. Humans and mammals will come in contact with this parasite by the consumption of contaminated or raw fish. This parasite is one of the smallest endoparasite to infect humans. It can cause intestinal infection called heterophyiasis.
Batillaria attramentaria, common name the Japanese mud snail, is a marine gastropod mollusk in the family Batillariidae. It is a species of sea snail most often found in the salt marshes and mudflats of marine, estuarine, riparian and wetland habitats. Introduced to North America between the 1920s to 1930s via the coasts of Washington and California, the Japanese mud snail became an invasive species notorious for reducing biodiversity by outcompeting the native hornsnail Cerithidea californica.
Cerithideopsis costata is a species of small sea snail, a marine gastropod mollusk in the family Potamididae.
Cerithideopsis pliculosa, common name the plicate horn shell, is a species of sea snail, a marine gastropod mollusk in the family Potamididae.
Cerithideopsis scalariformis, commonly known as the ladder hornsnail, is a species of sea snail, a marine gastropod mollusk in the family Potamididae. This amphibious species occurs in the western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico. The maximum recorded shell length is 33 mm (1.3 in).
Bithynia siamensis is a species of a freshwater snail with a gill and an operculum, an aquatic prosobranch gastropod mollusk in the family Bithyniidae.
Homalometron pallidum is a species of marine trematodes in the family Apocreadiidae. It is an endoparasite of the mummichog, Fundulus heteroclitus, a small fish found in brackish water along the east coast of the United States and Canada. It has a complex life cycle and lives inside several different host species at different stages.
Cerithideopsis is a genus of medium-sized sea snails or mud snails, marine gastropod mollusks in the family Potamididae, the horn snails.
Parorchis acanthus is a parasitic flatworm of the class Trematoda. It is a parasitic castrator of the common periwinkle Littorina littorea. Unlike many trematode species it encysts on hard surfaces and not inside a second intermediate host.
