n. Trematoda, clase de gusanos parásitos de la especie de los Platyhelminthes que incluye la duela y los gusanos planos que infectan el organismo humano. On Jan 1, , David I Gibson and others published Keys to the Trematoda. y fecha de publicación), grupo según sea el caso (Orden o Clase taxonómica). (Trematoda: Didymozoidae) y Sphyriocephalus tergestinus Pintner, . Trematodes and cestodes were .. Clase Cestoda Rudolphi,

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Animalia – Platyhelminthes – Trematoda

Around 6, species have been described to date. They are clearly closely related, descended from a common ancestor among the turbellarians. The giant liver fluke, Fascioloides magna, is a trematode parasite that infects the livers of white-tailed deer Odocoileus virginianuselk Cervus canadensisand caribou Rangifer tarandus across North America Fig.

A monostome is a worm with one sucker oral. Am Mus Novitates The vast majority of digeneans are hermaphrodites. Once thought to be related to the Monogeneait is now recognised that they are closest to the Aspidogastrea and that the Monogenea are more closely allied with the Cestoda.

But other phyla of small worms share some of the characters that clade set flatworms apart. Dis — double, Genos — race is a class of trematodes in the Platyhelminthes phylumconsisting of parasitic flatworms tremagoda as flukes with a syncytial tegument and, usually, two suckersone ventral and one oral.

Only about 12 of the 6, known species are infectious to humans, but some of these species are important diseases afflicting over million people.

Haszprunar G Plathelminthes and Plathelminthomorpha — paraphyletic taxa. Wikimedia Commons has media related to Digenea. Int J Dev Biol Overall prevalence of each trematode taxon and prevalence in each season was calculated following Bush, Lafferty, Lotz and Shostak Los trematodes encontrados fueron: Microphalloidea from fishes of the waters around New Caledonia, with the description of Overstreetia cribbi n.


Because the most recently analyzed molecular characters indicate a rather distant relationship between the Acoelomorpha and the other flatworms see belowit has been removed as a separate phylum, leaving Catenulida and Rhabditophora together by default in the phylum Platyhelminthes.


Opecoelidae from the intestine of a Flame Cardinal fish. The Acoelomorpha shares no apomorphies with both the Catenulida and Rhabditophora except possibly the presence of special stem cells called neoblasts Rieger and Ladurner, Turbellaria, Monogenea, Trematoda, and Cestoda. And though obviously a convergent similarity, the character of biflagellate spermatozoa is seen in some groups of fishes.

BMC Evolutionary Biol http: Jennings JB Parasitism and commensalism in the Turbellaria. The term “turbellarian” is still a useful moniker referring to all those worms formerly classified in the Turbellaria, but the term “Turbellaria” specifically, the capitalized taxon name would have to be written in quotation marks to indicate its paraphyletic status.

Digenea – Wikipedia

They can live for several years and produce many thousands of eggs. Alternatively, eggs may hatch in water to release an actively swimming, ciliated larva, the miracidiumwhich must locate and penetrate the body wall of the snail host.

There is no study on the trematode parasites of Lophius piscatorius. Eleven orders of turbellarians are recognized in the commonly used classification that Trematod championed Tyler, East AsiaNorth America. These flukes generally cause mild pathology in humans, but more serious effects may also occur. Hallazgo de Fasciola hepatica en bufalos faenados en Misiones Argentina.

Most species inhabit the human gastrointestinal tract, where they shed eggs along with host feces. Turbellarian platyhelminths; representatives of 4 of the 11 orders of turbellarians. In some species the two gut caeca join posteriorly to make a ring-shaped gut or cyclocoel.


Since the absence of meiotic processes is not proven, the exact definition remains doubtful. It is thought that the early trematodes the collective name for digeneans and aspidogastreans likely evolved from rhabdocoel turbellarians that colonised the open mantle cavity of early molluscs.

That larva has an epidermis much like that of turbellarians, composed of ciliated cells. Academic Press, New York. Aspidogastridae em Pogonias cromis Linnaeus, Perciformes: Encysted metacercarial stages and free-living cercarial stages do not feed. In other projects Wikimedia Commons Wikispecies.

Jennings JB Nutritional and respiratory pathways to parasitism exemplified in the turbellaria. The mother sporocyst undergoes a round of internal asexual reproductiongiving rise to either rediae sing.

Exactly where the Neodermata came from among turbellarian platyhelminths is not at all clear; a number of potential ancestral groups have been proposed Ehlers, ; Brooks, ; Littlewood et al. The Acoela, on the other hand, appears to share with the Rhabditophora the homology of biflagellate spermatozoa, but since catenulids don’t have such sperm and since the Nemertodermatida, the sister group to the Acoela in the Acoelomorpha, also lack such spermthis homology would negate those homologies listed between Catenulida and Rhabditophora.

The quintessential parasitic flatworms are the monogeneans, trematodes, and cestodes, and these constitute monophyletic groups, but by a cladistic classification, these monophyletic groups would not have the rank of class.

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