Gigantorhynchus is a genus of Acanthocephala that parasitize marsupials, anteaters, and possibly baboons by attaching themselves to the intestines using their hook-covered proboscis. Their life cycle includes an egg stage found in host feces, a cystacanth (larval) stage in an intermediate host such as termites, and an adult stage where cystacanths mature in the intestines of the host. This genus is characterized by a cylindrical proboscis with a crown of robust hooks at the apex followed by numerous small hooks on the rest of the proboscis, a long body with pseudosegmentation, filiform lemnisci, and ellipsoid testes. The largest known specimen is the female G. ortizi with a length of around 240 millimetres (9.4 in) and a width of 2 millimetres (0.08 in). Genetic analysis on one species of Gigantorhynchus places it with the related genus Mediorhynchus in the family Gigantorhynchidae. Six species in this genus are distributed across Central and South America and possibly Zimbabwe. Infestation by a Gigantorhynchus species may cause partial obstructions of the intestines, severe lesions of the intestinal wall, and may lead to death.
Mediorhynchus is a genus of small parasitic spiny-headed worms. Phylogenetic analysis has been conducted on two known species of Mediorhynchus and confirmed the placement along with the related genus Gigantorhynchus in the family Gigantorhynchida. The distinguishing features of this order among archiacanthocephalans is a divided proboscis. This genus contains fifty-eight species that are distributed globally. These worms exclusively parasitize birds by attaching themselves around the cloaca using their hook-covered proboscis. The bird hosts are of different orders.
Oligacanthorhynchida is an order containing a single parasitic worm family, Oligacanthorhynchidae, that attach themselves to the intestinal wall of terrestrial vertebrates.
Acanthocephaloides is a genus of parasitic worms belonging to the family Arhythmacanthidae.
Cucullanorhynchus is a monotypic genus of acanthocephalans. It contains a single species, Cucullanorhynchus constrictruncatus, which infests leopards in Vietnam.
Prosthenorchis is a genus of parasitic worms belonging to the family Oligacanthorhynchidae. Prosthenorchis have a trunk up to 50 mm long, a proboscis that is not ornate with three barbed hooks in each of 12 rows. They have complex hook roots with large manubria, and a small discoid posterior hook base. There are up to 23 festoons. Gonopore is subterminal. The primary host are primates in South America and Felidae in Africa with cockroaches and beetles as intermediate hosts.
Macracanthorhynchus, also known as the giant thorny-headed worm of swine, is a member of the Oligacanthorhynchidae which contains four species.
Multisentis is a monotypic genus of acanthocephalans. It contains a single species, Multisentis myrmecobius , parasite of the numbat from which it derives its species name. It was found in south-western Australia.
Neoncicola is a genus of parasitic worms containing nine species and belongs to the family Oligacanthorhynchidae.
Oligacanthorhynchus is a genus of parasitic worms belonging to the family Oligacanthorhynchidae.
Eocollis is a genus in Acanthocephala.
Machadosentis is a monotypic genus of acanthocephalans containing a single species, Machadosentis travassosi, that infests animals.
Pararaosentis is a monotypic genus of acanthocephalans containing a single species, Pararaosentis golvani.
Triaspiron is a monotypic genus of acanthocephalans containing a single species, Triaspiron aphanii.
Caballerorhynchus is a monotypic genus of acanthocephalans containing a single species, Caballerorhynchus lamothei, that infests animals.
Pallisentis is a genus in Acanthocephala.
Gorytocephalus is a genus in Acanthocephala belonging to the family Neoechinorhynchidae.
Octospiniferoides is a genus in Acanthocephala belonging to the family Neoechinorhynchidae.
Intraproboscis is a monotypic genus of acanthocephalans that infest African black-bellied pangolin in the Central African Republic. Its body consists of a proboscis armed with hooks which it uses to pierce and hold the gut wall of its host, and a long trunk. It contains a single species, Intraproboscis sanghae. This genus resembles species in the genus Mediorhynchus but is characterized by infesting a mammal instead of birds, and having a simple proboscis receptacle that is completely suspended within the proboscis, the passage of the retractor muscles through the receptacle into the body cavity posteriorly, absence of neck, presence of a parareceptacle structure, and a uterine vesicle. The proboscis is armed with 34–36 rows of 6 to 7 hooks anteriorly and 15–17 spinelike hooks posteriorly which are used to attach themselves to the intestines of the host. The female worms are up to 180 millimetres long, virtually all of which is the trunk, and 2 millimetres wide.
Acanthodelta is a genus of acanthocephalan.
