''Ancistomus spinosissimus'' 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 The Loricariidae is the largest family of catfish (order Siluriformes), with 92 genera and just over 680 species. Loricariids originate from freshwater habitats of Costa Rica, Panama, and tropical and subtropical South America. These fish are not ...

. It is a

freshwater fish Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 1.05%. These environments differ from marine conditions in many ways, especially the difference in levels of ...

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 sout ...

, where it is known only from the upper and middle

Tocantins River The Tocantins River ( pt, Rio Tocantins, link=no , , Parkatêjê: ''Pyti'' ɨˈti is a river in Brazil, the central fluvial artery of the country. In the Tupi language, its name means " toucan's beak" (''Tukã'' for "toucan" and ''Ti'' for "beak ...

basin in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. The species reaches 12.7 cm (5 inches) in standard length. Although originally described as a species 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 ...

'' in 2003, a 2015 review conducted by Jonathan W. Armbruster (of Auburn University), David C. Werneke, and Milton Tan listed the species as valid within '' Ancistomus''.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 The same review also reported that no characteristics were found to separate ''A. spinosissimus'' from its congeners '' A. micrommatos'' and '' A. spilomma'', indicating that the three may actually all be the same species.

References

{{Taxonbar, from=Q115729257 Fish described in 2003 Hypostominae