| Pallisentis | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Acanthocephala |
| Class: | Eoacanthocephala |
| Order: | Gyracanthocephala |
| Family: | Quadrigyridae |
| Subfamily: | Pallisentinae |
| Genus: | Pallisentis Van Cleave, 1928 |
Pallisentis is a genus in Acanthocephala (parasitic thorny-headed worms, also known as spiny-headed worms).
The genus Pallisentis has three subgenera: Brevitritospinus, Demidueterospinus, and Pallisentis. The National Center for Biotechnology Information indicates that a phylogenetic analysis has been published on Pallisentis celatus. [1]
Pallisentis species consists of a proboscis covered in hooks and a trunk.
PallisentisVan Cleave, 1928 is divided into three subgenera: Brevitritospinus, Demidueterospinus, and Pallisentis with 26 species: [2]
Host: Channa punctatus in Bareilly, Uttar Pradesh, India.
P. singaporensis has 8 to 12 proboscis hooks per circle, gradually declining in size posteriorly. They measure from the anterior are 62 to 64, 49 to 54, 36 to 46 and 24 to 28 um long. The trunk spines are conical and do not extend to the posterior end in 25 or 26 circles, each with 10 spines. In the male, the cement gland is long and has 23 to 25 giant nuclei and lack Saefftigen's pouch. They have unequal lemnisci. The female gonopore is terminal. [5]
The distribution of Pallisentis species is determined by that of its hosts.
The life cycle of an acanthocephalan consists of three stages beginning when an infective acanthor (development of an egg) is released from the intestines of the definitive host and then ingested by an arthropod, the intermediate host. The intermediate hosts of most Pallisentis species are not known. When the acanthor molts, the second stage called the acanthella begins. This stage involves penetrating the wall of the mesenteron or the intestine of the intermediate host and growing. The final stage is the infective cystacanth which is the larval or juvenile state of an Acanthocephalan, differing from the adult only in size and stage of sexual development. The cystacanths within the intermediate hosts are consumed by the definitive host, usually attaching to the walls of the intestines, and as adults they reproduce sexually in the intestines. The acanthor is passed in the feces of the definitive host and the cycle repeats. [8]
There are no reported cases of any Pallisentis species infesting humans in the English language medical literature. [7]
Quadrigyridae is the only family within Gyracanthocephala, an order of parasitic worms of class Eoacanthocephala. This family contains two subfamilies, ten genera and about 92 species.
Acanthocephalus is a genus of parasitic worms. One of the species in this genus is Acanthocephalus anguillae, a fish parasite. Acanthocephalans are also found in humans and primates, causing a common zoonotic infection called "human acanthocephaliasis". While pathogens can be transferred among animals and humans, the main source of human acanthocephaliasis is the diet of infected raw fish and insects. Because they are lacking circulatory, respiratory, and digestive systems, Acanthocephalus are exceptionally well-adapted to a symbiotrophic existence.
Profilicollis is a genus of acanthocephalan parasites of crustaceans. The status of the genus Profilicollis has been debated, and species placed in this genus were formerly included in the genus Polymorphus. However, research on the morphology of the group and their use of hosts has concluded that Profilicollis and Polymorphus should be regarded as distinct genera, and species previously described as Polymorphus altmani are now referred to as Profilicollis altmani in taxonomic and biological literature. Profilicollis parasites infect decapod crustaceans, usually shore crabs, as intermediate hosts, and use many species of shorebirds as definitive (final) hosts.
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.
Cavisomidae are a family of parasitic worms from the order Echinorhynchida.
Leptorhynchoididae is a family of parasitic worms from the order Echinorhynchida.
Rhadinorhynchidae is a family of parasitic worms from the order Echinorhynchida.
Plagiorhynchidae is a family of parasitic Acanthocephalan worms.
Polymorphus is a genus of parasitic worms from the phylum Acanthocephala. This group uses amphipod crustaceans as intermediate hosts and various birds as final hosts.
Cucullanorhynchus is a monotypic genus of acanthocephalans. It contains a single species, Cucullanorhynchus constrictruncatus, which infests leopards in Vietnam.
Paraprosthenorchis is a monotypic genus of acanthocephalans. It contains a single species, Paraprosthenorchis ornatus, which infests the Chinese pangolin in Vietnam.
Macracanthorhynchus, also known as the giant thorny-headed worm of swine, is a member of the Oligacanthorhynchidae which contains four species.
Oligacanthorhynchus is a genus of parasitic worms belonging to the family Oligacanthorhynchidae.
Floridosentis is a genus in Acanthocephala.
Quadrigyrus is a genus in Acanthocephala.
Pararaosentis is a monotypic genus of acanthocephalans containing a single species, Pararaosentis golvani.
Gracilisentis is a genus in Acanthocephala.
Neoechinorhynchus is a genus of parasitic worms belonging to the family Neoechinorhynchidae.
Dispiron 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.