''Chimaericola leptogaster'' is a species of

polyopisthocotylea Polyopisthocotylea is a subclass of parasitic flatworms in the class Monogenea.WoRMS (2023). Polyopisthocotylea. Accessed at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=119220 on 2023-12-21Yamaguti, S. (1963). Systema Helminthum Volu ...

monogenea Monogeneans, members of the class Monogenea, are a group of ectoparasitic flatworms commonly found on the skin, gills, or fins of fish. They have a direct lifecycle and do not require an intermediate host. Adults are hermaphrodites, meaning they ...

n in the family Chimaericolidae. It is ectoparasitic on the

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

of the chimaera '' Chimaera monstrosa''.

History

According to Brinkmann,Brinkmann Jr, A. (1942). On ''Octobothrium leptogaster'' FS Leuckart. Goteborgs Kungliga Vetenskaps-och Vitterhets-Samhalles Handlingar. Series B, 2(3), 1-29. the species was discovered as early as 1828 on the gills of

chimaeras Chimaeras are Chondrichthyes, cartilaginous fish in the order (biology), order Chimaeriformes (), known informally as ghost sharks, rat fish (not to be confused with rattails), spookfish, or rabbit fish; the last two names are also applied to B ...

off Norway by Rapp and was given a scientific name by

Friedrich Sigismund Leuckart Friedrich Andreas Sigismund Leuckart (26 August 1794 – 25 August 1843) was a German doctor and naturalist. He was born in Helmstedt in Lower Saxony and studied medicine at the University of Göttingen. From 1816 he made several voyages of explor ...

in 1830, as ''Octobothrium leptogaster'', but Leuckart did not see the animal. The species was then mentioned by

Félix Dujardin Félix Dujardin (5 April 1801 – 8 April 1860) was a French biologist born in Tours. He is remembered for his research on protozoans and other invertebrates. Biography In 1840 Dujardin was appointed professor of geology and mineralogy at t ...

and

Karl Moriz Diesing Karl Moriz Diesing (also written as Carl Moritz Diesing; 16 June 1800 – 10 January 1867) was an Austrians, Austrian naturalist and zoologist, specializing in the study of helminthology. Biography Diesing was born on 16 June 1800 in Kraków. He ...

, who also did not see the specimens. However, Diesing transferred the species to the genus '' Discocotyle'' but also considered the species as "species inquirenda". Later, in 1858, Diesing transferred the species to the genus ''Placoplectanum''. Olsson redescribed the animal in 1876 Olsson, P. (1876). Bidrag till skandinaviens helminthfauna. I. Kongl. Svenska Vetenskaps-Akademiens Handlingar 14(1), 1-41 and used again the name ''Octobothrium leptogaster''. The species was shortly redescribed by Parona & Perugia in 1892. Finally Brinkmann redescribed the species in details in 1942 from material collected off

Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of the Kingdom of ...

and

Sweden Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

Morphology

''Chimaericola leptogaster'' is a large

n, reaching 50 mm in length. The

haptor The haptor is the attachment organ of the monogeneans, a group of parasitic Platyhelminthes. The haptor is sometimes called opisthaptor (from ''opistho-'': behind) to emphasize that it is located in the posterior part of the body, and to diffe ...

, at the posterior end of the body, bears eight

clamps Clamp may refer to: Tools and devices *Brick clamp, an early method of baking bricks *Clamp (tool), a device or tool used to hold objects in a fixed relative position (many types listed) **C-clamp **C-clamp (stagecraft) **Riser clamp, a device u ...

arranged as two rows of four.

Modern works

The first molecular sequences obtained from ''Chimaericola leptogaster'' suggested that the Chimaericolidae were a basal group within the Polyopisthocotylea. ''Chimaericola leptogaster'' was studied with

transmission electron microscopy Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a g ...

. Several organs have been investigated in details:

vagina In mammals and other animals, the vagina (: vaginas or vaginae) is the elastic, muscular sex organ, reproductive organ of the female genital tract. In humans, it extends from the vulval vestibule to the cervix (neck of the uterus). The #Vag ...

, digestive system, and

spermiogenesis Spermiogenesis is the final stage of spermatogenesis, during which the spermatids develop into mature spermatozoon, spermatozoa. At the beginning of the stage, the spermatid is a more or less circular cell containing a cell nucleus, nucleus, Golg ...

and

spermatozoa A spermatozoon (; also spelled spermatozoön; : spermatozoa; ) is a motile sperm cell (biology), cell produced by male animals relying on internal fertilization. A spermatozoon is a moving form of the ploidy, haploid cell (biology), cell that is ...

. These ultrastructural results have confirmed the basal position of the species in comparison to marine

Polyopisthocotylea Polyopisthocotylea is a subclass of parasitic flatworms in the class Monogenea.WoRMS (2023). Polyopisthocotylea. Accessed at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=119220 on 2023-12-21Yamaguti, S. (1963). Systema Helminthum Volu ...

References

{{Authority control Polyopisthocotylea Fauna of Norway Fauna of Sweden Animals described in 1830