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

trematode Trematoda is a Class (biology), class of flatworms known as trematodes, and commonly as flukes. They are obligate parasite, obligate Endoparasites, internal parasites with a complex biological life cycle, life cycle requiring at least two Host ( ...

flatworm Platyhelminthes (from the Greek language, Greek πλατύ, ''platy'', meaning "flat" and ἕλμινς (root: ἑλμινθ-), ''helminth-'', meaning "worm") is a Phylum (biology), phylum of relatively simple bilaterian, Segmentation (biology), ...

s that are parasites of

molluscs Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

and

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

. Like other

Bucephalidae Bucephalidae is a family of trematodes that parasitize fish. They lack suckers, having instead a muscular organ called a "rhynchus" at the front end which they use to attach to their hosts. The characteristics of the rhynchus are used to help d ...

, they are found in fish both as adults and as

metacercariae Trematodes are parasitic flatworms of the class ''Trematoda'', specifically parasitic flukes with two Sucker (zoology), suckers: one ventral and the other Mouth, oral. Trematodes are covered by a Tegument (helminth), tegument, that protects the o ...

. In marine and freshwater

teleosts Teleostei (; Greek ''teleios'' "complete" + ''osteon'' "bone"), members of which are known as teleosts (), is, by far, the largest group of ray-finned fishes (class Actinopterygii), with 96% of all extant species of fish. The Teleostei, which i ...

, 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 A cercaria (plural cercariae) is a larval form of the trematode class of parasites. It develops within the germinal cells of the Trematode life cycle stages, sporocyst or redia. A cercaria has a tapering head with large penetration glands. It may ...

larva.

Siebold Siebold or von Siebold is a German language, German surname. It is a patronymic surname derived from the given name Siebold, which consists of the Old High German words ''sigu'' ("Victory") and ''bold'' ("strong"). Notable people with the surname ...

(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 is a specialised attachment organ of an animal. It acts as an adhesion device in parasitic worms, several flatworms, cephalopods, certain fishes, amphibians, and Myzopoda, bats. It is a muscle, muscular structure for suction on ...

. 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