Family Arhythmacanthidae

## Source: Wikipedia

**Arhythmacanthidae** is a family of parasitic worms from the order Echinorhynchida.

## Species

There are 9 genera in the family *Arhythmacanthidae* which contains the following species:

***Acanthocephaloides*** Meyer, 1932

* ***Acanthocephaloides claviformis*** Araki & Machida, 1987

Found off Japan. The proboscis has 14 rows each of 6 hooks and 2 spines and the trunk has an anterior swelling. The apical hooks are the smallest; posterior hook largest, reaching up to 74 um. Hook and spine roots (when present) invariably simple, posteriorly directed, without manubria. Trunk spines are markedly smaller, with a variable distribution of trunk spines only on the anterior side.

* ***Acanthocephaloides cyrusi*** Bray, Spencer-Jones & Lewis, 1988

*A. cyrusi* has been found parasitizing the fish: Blackhand sole (*Pegusa nasuta* referred to by its synonym *Solea bleekeri*) and the Small-spotted grunter (*Pomadasys commersonnii*) in Lake St. Lucia, Natal, South Africa. It is distinguished from the other species in the genus *Arhythmacanthidae* by the more greater sexual dimorphism in length, differing arrangement of hooks, the proboscis with the longest hooks at the anterior-most part and the larger size of proboscis hooks and body spines. Specifically, the proboscis hook rows with 3 spines and 3 hooks that increase in size anteriorly. Apical hook reaches 83–101 or 118–137 um in length and has root with large, oblique, anterior manubrium. Posterior spines rootless. Whole trunk with regular transverse rows of uniform, acuminate, 13–22 um long spines.

* ***Acanthocephaloides delamuri*** (Parukhin, 1989) Amin, 2013
* ***Acanthocephaloides distinctus*** Golvan, 1969

Found off Senegal.

* ***Acanthocephaloides geneticus*** (Buron, Renaud & Euzet, 1985)

Found off the Mediterranean coast of France.

* ***Acanthocephaloides ichiharai*** Araki & Machida, 1987

Found off Japan. The proboscis has variable 13–14 (rarely 12 or 16) hook rows of 10–12 hooks/spines (9 hooks and 3 rootless spines in 1 specimen). Hook and spine roots (when present) invariably simple, posteriorly directed, without manubria with the apical hook being the smallest; posterior hook largest, and reaching up to 74 um. The trunk is cylindrical and has spines only on the anterior portion smaller than probiscus hooks and variable in their distribution.

* ***Acanthocephaloides irregularis*** Amin, Oğuz, Heckman, Tepe & Kvach, 2011

*A. irregularis* is found parasitizing the Combtooth blenny (*Parablennius zvonimiri*) in the Gulf of Odessa, Ukraine, the Mushroom goby (*Ponticola eurycephalus*) in the Sukhyi Estuary, in the Black Sea, and the Tubenose goby (*Proterorhinus marmoratus*) and Black-striped pipefish (*Syngnathus abaster*) in both locations. The species is named for its irregular distribution of trunk spines. *A. irregularis* is most similar to its closest relative, *A. propinquus* in proboscis shape and armature as both have 12 longitudinal rows of 5 hooks each and the shape of the trunk, reproductive system and lemnisci. *A. irregularis* differs from *A. propinquus* in having randomly distributed trunk spines that are organised in circular rings of individual spines separated by aspinose zones. *A. irregularis* is also unique in having an anterior trunk collar, a very large triangular cephalic ganglion, nucleated pouches at the posterior end of the proboscis receptacle, and hooks and spines with roots bearing anterior manubria. It is the tenth species of the genus to be described.

* ***Acanthocephaloides neobythitis*** (Yamaguti, 1939) Amin, 2013

Found off Japan.

* ***Acanthocephaloides nicoli*** (Kumar, 1992) Amin, 2013
* ***Acanthocephaloides plagiusae*** Santana-Pineros, Cruz-Quintana, Centeno-Chale & Vidal-Martinez, 2013
* ***Acanthocephaloides propinquus*** (Dujardin, 1845)

*A. propinquus* was found parasitizing *Uranoscopus scaber*, *Gobius niger*, *Gobius cobitis*, *Merluccius merluccius*, *Scorpaena scrofa*, *Eutrigla gurnardus*, and *Solea vulgaris* in the bay of Gemlik, Turkey. It is also found in the Atlantic Ocean, Mediterranean Sea and Black Sea. The body is between 2600 and 6237 µm long and between 140 and 280 µm wide. The eggs were between 30 and 64 µm long and 10 to 16 µm wide.

* ***Acanthocephaloides rhinoplagusiae*** (Yamaguti, 1935) Amin, 2013

Found off Japan.

* ***Acanthocephaloides spinicaudatus*** (Cable & Quick, 1954) Pichelin & Cribb, 1999

Found off Puerto Rico.

***Bolborhynchoides*** Achmerov and Dombrovskaja-Achmerova, 1959

* ***Bolborhynchoides exiguus*** (Achmerow & Dombrowskaja-Achmerova, 1941)

***Breizacanthus*** Golvan, 1969

* ***Breizacanthus aznari*** Hernández-Orts, Alama-Bermejo, Crespo, García, Raga & Montero, 2012
* ***Breizacanthus chabaudi*** Golvan, 1969
* ***Breizacanthus golvani*** Gaevskaja & Shukhgalter, 1984
* ***Breizacanthus irenae*** Golvan, 1969
* ***Breizacanthus ligur*** Paggi, Orecchia & Della Setta, 1975

***Euzetacanthus*** Golvan and Houin, 1964

* ***Euzetacanthus chorinemusi*** Gupta & Naqvi, 1984
* ***Euzetacanthus golvani*** Gupta & Fatma, 1985
* ***Euzetacanthus simplex*** (Rudolphi, 1810)

***Heterosentis*** Van Cleave, 1931

* ***Heterosentis brasiliensis*** Vieira, Felizardo & Luque, 2009
* ***Heterosentis fusiformis*** (Yamaguti, 1935) Tripathi, 1959
* ***Heterosentis heteracanthus*** (Linstow, 1896) Van Cleave, 1931

*H. heteracanthus* was found parasitizing *Patagonotothen longipes*, *Patagonotothen tessellata* and *Champsocephalus esox* in the eastern mouth of the Beagle Channel.

* ***Heterosentis hirsutus*** Pichelin & Cribb, 1999
* ***Heterosentis holospinus*** Amin, Heckman & Ha, 2011

*H. holospinus* has been found parasitizing the Striped eel catfish (*Plotosus lineatus*), in Halong Bay, Vietnam.

* ***Heterosentis martini*** Lanfranchi & Timi, 2011
* ***Heterosentis mongcai*** Amin, Heckmann & Ha, 2014
* ***Heterosentis mysturi*** Wei, Huang, Chen and Jiang, 2002
* ***Heterosentis overstreeti*** (Schmidt & Paperna, 1978) Amin, 1985
* ***Heterosentis paraplagusiarum*** (Nickol, 1972) Amin, 1985
* ***Heterosentis plotosi*** (Yamaguti, 1935) Schmidt & Paperna, 1978
* ***Heterosentis septacanthus*** (Sita in Golvan, 1969) Amin, 1985
* ***Heterosentis thapari*** (Gupta & Fatma, 1979) Amin, 1985
* ***Heterosentis zdzitowieckii*** (Kumar, 1992) Pichelin & Cribb, 1999

***Hypoechinorhynchus*** Yamaguti, 1939

* ***Hypoechinorhynchus alaeopis*** Yamaguti, 1939
* ***Hypoechinorhynchus golvani*** Gutpa & Kumar, 1987
* ***Hypoechinorhynchus magellanicus*** Szidat, 1950

*H. magellanicus* was found parasitizing *Champsocephalus esox* in the eastern mouth of the Beagle Channel.

* ***Hypoechinorhynchus robustus*** Pichelin, 1999
* ***Hypoechinorhynchus thermaceri*** Buron, 1988
* ***Paracanthocephaloides*** Golvan, 1969

Worms in this genus have no trunk spines.

* ***Paracanthocephaloides caballeroi*** (Gupta & Fatma, 1983) Bhattacharya, 2007
* ***Paracanthocephaloides chabanaudi*** (Dollfus, 1951)
* ***Paracanthocephaloides incrassatus*** (Molin, 1858) Meyer, 1932
* ***Paracanthocephaloides tripathii*** Golvan, 1969

***Solearhynchus*** de Buron and Maillard, 1985

The proboscis hooks gradually decrease in size posteriorly.

* ***Solearhynchus kostylewi*** (Meyer, 1932)

*S. kostylewi* was found parasitizing *Solea vulgaris* in the bay of Gemlik, Turkey. The body was between 7404 and 7854 µm long and 739 and 1040 µm wide. The anterior part of the body was wider than the posterior. The proboscis was cylindrical and armed with 16 rows of hooks each with 5 or 6 hooks the longest hooks being in the middle of the proboscis. The smallest basal spinelike hooks were unrooted. The testes were located centrally in the body distant from the six cement glands. The eggs measured between 42 – 64µm long and between 12 and 20µm wide.

* ***Solearhynchus soleae*** (Porta, 1905)

*S. soleae* was found parasitizing *Solea vulgaris* in the bay of Gemlik, Turkey. The body was from 5382 to 20328 µm long and 693 to 1200 µm wide. The proboscis was from 224 – 320 µm long and the proboscis sac was between 277 and 480 µm long. The proboscis has 12 – 14 rows of hooks each comprising 5 or 6 hooks. The longest hooks were in the middle of the proboscis and the smallest basal hooks were unrooted and resembled spines. The lemnisci were longer than the proboscis sac, measuring between 312 and 350 µm and between 312 – 349 µm long. Males had two testes in the posterior part of the body distant from six piriform cement glands. The eggs measured between 56 and 68 µm long and between 12 and 20 µm wide. This species was also recorded in the Black Sea by Belofastova and Korniychuk (as the synonym *Acanthocephaloides rhytidotes*). The species name *soleae* derives from the genus name of the host, the Adriatic sole (Originannly named *Solea impar*, now named *Pegusa impar*).

***Spiracanthus*** Muñoz and George-Nascimento, 2002

* ***Spiracanthus bovichthys*** Munoz & George-Nascimento, 2002

## Hosts

*Arhythmacanthidae* species parasitize fish.

* Hosts for *Arhythmacanthidae* species
* The Small-spotted grunter is a host of *Acanthocephaloides claviformis*.
* The Combtooth blenny is one of the hosts of *Acanthocephaloides irregularis*.
* The Mushroom goby is one of the hosts of *Acanthocephaloides irregularis*.
* The Tubenose goby is one of the hosts of *Acanthocephaloides irregularis*.
* The Black-striped pipefish is one of the hosts of *Acanthocephaloides irregularis*.
* *Heterosentis holospinus* parasitizes the Striped eel catfish.

## Notes

1. **^** A binomial authority in parentheses indicates that the species was originally described in a genus other than the present genus.
2. **^** *Solearhynchus soleae*, was originally described as *Echinorhynchus soleae* by Porta in 1905 and re-described by Meyer in 1933 as *Acanthocephaloides soleae*. De Buron and Maillard later (1985) placed it in the genus Solearhynchus.