''Bucephalus'' () is the genus name for many trematode

flatworm The flatworms, flat worms, Platyhelminthes, or platyhelminths (from the Greek πλατύ, ''platy'', meaning "flat" and ἕλμινς (root: ἑλμινθ-), ''helminth-'', meaning "worm") are a phylum of relatively simple bilaterian, unsegment ...

s that are parasites of molluscs and fish. Like other Bucephalidae, they are found in fish both as adults and as metacercariae. In marine and freshwater teleosts, they live as parasites inside the digestive tract, especially the intestine. Haeckel Platodes Bucephalus

The genus ''Bucephalus'' was based on the earliest known bucephalid, '' B. polymorphus'' Baer (1827), initially described from a cercaria larva.

Siebold Siebold or von Siebold is a German surname: * Carl Caspar von Siebold (1736–1807), surgeon * Regina von Siebold (1771–1849), obstetrician * Adam Elias von Siebold (1775–1828), medical doctor * Charlotte von Siebold (1788–1859), gynaecol ...

(1848) believed that the adult bucephalid he named ''Gasterostomum fimbriatum'' represented an adult form of the same bucephalid, but this identity has never been proved. The name ''Bucephalus'' () was chosen because of the horn-like appearance of the forked tail (furcae) of its cercaria. By what Manter calls a "curious circumstance", horns are also suggested by the long tentacles of adult worms. They are distinguished from other genera in the same family by having tentacles associated with the

anterior sucker A sucker in zoology refers to a specialised attachment organ of an animal. It acts as an adhesion device in parasitic worms, several flatworms, cephalopods, certain fishes, amphibians, and bats. It is a muscular structure for suction on a host or ...

. Genus members have their mouth in the middle of the body. An earlier name for this genus was ''Gasterostomum'', given by von Siebold in 1848 to all adult trematodes with a ventral mouth. Odhner (1905) established two suborders of digenean trematodes called Gasterostomata and Protostomata. The two genera in Gasterostomata were ''Gasterostomum'' (now ''Bucephalus'') and ''Prosorhynchus,'' of which the former has an anterior sucker separate from its digestive tract and the latter has an anterior rhynchus. Members of the genus ''Bucephalus'' are also sometimes referred to as "gasterostomes."

References

{{Taxonbar, from=Q4982517 Plagiorchiida Plagiorchiida genera