'''Pseudancistrus' megacephalus'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

catfish Catfish (or catfishes; order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, ...

in the family Loricariidae. It is of uncertain and disputed classification.Armbruster, J. W., Werneke, D. C., & Tan, M. (2015). Three new species of saddled loricariid catfishes, and a review of Hemiancistrus, Peckoltia, and allied genera (Siluriformes). ''ZooKeys'', (480), 97–123. https://doi.org/10.3897/zookeys.480.6540

Description

'''P.' megacephalus'' is a small-to-medium-sized loricariid, reaching 12.3 cm (4.8 inches) in

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

Distribution

'''P.' megacephalus'' is native to

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

, where it occurs in the Essequibo River basin in

Guyana Guyana ( or ), officially the Cooperative Republic of Guyana, is a country on the northern mainland of South America. Guyana is an indigenous word which means "Land of Many Waters". The capital city is Georgetown. Guyana is bordered by the ...

, as well as the

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

coastal drainage of

Suriname Suriname (; srn, Sranankondre or ), officially the Republic of Suriname ( nl, Republiek Suriname , srn, Ripolik fu Sranan), is a country on the northeastern Atlantic coast of South America. It is bordered by the Atlantic Ocean to the north ...

. The exact locality at which it has been found within Suriname's coastal drainage is unknown, although its presence in the region has been stated.

Taxonomy

'''P.' megacephalus'' was originally described as ''Chaetostomus megacephalus'' by

Albert Günther Albert Karl Ludwig Gotthilf Günther FRS, also Albert Charles Lewis Gotthilf Günther (3 October 1830 – 1 February 1914), was a German-born British zoologist, ichthyologist, and herpetologist. Günther is ranked the second-most productive re ...

in 1868. In 1904, it was listed as a member of '' Ancistrus'' by Charles Tate Regan. In 1889, it was reclassified as a member of ''

Hemiancistrus ''Hemiancistrus'' is a genus of suckermouth armored catfishes. These species are native to South America. The taxonomy of this genus is complex and unclear, and major work has to be done. Many of these fish are popular aquarium fish. Taxonomy ' ...

'' by

Carl H. Eigenmann Carl Henry Eigenmann (March 9, 1863 – April 24, 1927) was a German-American ichthyologist of the late nineteenth and early twentieth centuries, who, along with his wife Rosa Smith Eigenmann, and his zoology students is credited with identifyin ...

and

Rosa Smith Eigenmann Rosa Smith Eigenmann (October 7, 1858 – January 12, 1947) was an American ichthyologist (the branch of zoology devoted to the study of fish), as well as a writer, editor, former curator at the California Academy of Sciences, and the first libra ...

, a classification which C. H. Eigenmann later used in 1912. This classification was subsequently followed by

Isaäc J. H. Isbrücker Isaäc Jan Hendrik Isbrücker (born 1944) is a retired Dutch ichthyologist who specialised in the scientific classification of South American catfish (Loricarioidea). Life and work Between 1960 and 1985 Isbrücker was a keeper of the aquarium in ...

in 1980, among others.

FishBase FishBase is a global species database of fish species (specifically finfish). It is the largest and most extensively accessed online database on adult finfish on the web.

and multiple other sources still place the species within ''Hemiancistrus''. In 2015, a review conducted by Jonathan W. Armbruster, David C. Werneke, and Milton Tan found the species ''Chaetostomus macrops'' (described in 1874 by

Christian Frederik Lütken Christian Frederik Lütken (; 7 October 1827, in Sorø – 6 February 1901), was a Denmark, Danish zoologist and naturalist. In 1852, he resigned his commission as a lieutenant with the Danish army, and earned his master's degree in sciences the ...

and also at some point placed within ''Hemiancistrus'') to be synonymous with '''P. ''megacephalus'', which was transferred to the genus ''

Pseudancistrus ''Pseudancistrus'' is a genus of suckermouth armored catfishes native to South America. Taxonomy ''Pseudancistrus'' is a genus in the tribe Ancistrini of the subfamily Hypostominae. It was described by Pieter Bleeker in 1862, and redescribed by ...

''. In 2018, it was suggested by Sonia Fisch-Muller, Jan Mol, and Raphaël Covain that '''P.' megacephalus'' may belong to'' Guyanancistrus,'' although its classification is still uncertain. Fisch-Muller, Mol, and Covain also suggested that ''Chaetostomus macrops'' may be a distinct species and not a synonym of'' 'P.' megacephalus''.Fisch-Muller, S., Mol, J., & Covain, R. (2018). An integrative framework to reevaluate the Neotropical catfish genus Guyanancistrus (Siluriformes: Loricariidae) with particular emphasis on the Guyanancistrus brevispinis complex. ''PloS one'', ''13''(1), e0189789. https://doi.org/10.1371/journal.pone.0189789

References

{{Taxonbar, from=Q6413994 Fish described in 1868 Ancistrini Fish of South America