Hemiancistrus
Encyclopedia
Hemiancistrus is a genus
of small South American armored suckermouth catfishes
. The taxonomy
of this genus is complex and unclear, and major work has to be done. Many of these fish are popular aquarium
fish.
Ancistrini
of the subfamily Hypostominae
. This genus has long been used as a sort of dump for Loricariid species; fish with unclear relationships have been classified to this genus. As such, this taxon is not monophyletic
. At this point, many undescribed
species remain.
This genus and the closely related Peckoltia
may be synonymous
, as neither genus is supported by synapomorphies
. Hemiancistrus species differ from other members of the Panaque
clade
lacking the synapomorphies of the other genera and having the dentaries meeting at an angle greater than 120°; in Peckoltia species, the dentaries meet at less than 90° Generally, Peckoltia are considered to be those that have dorsal saddles and bands in the fins, while Heminancistrus have spots and uniform coloration. Many species of Peckoltia may actually belong to Hemiancistrus.
What species belong to this genus has been unclear. Many newer species have been tentatively assigned to Hemiancistrus. Peckoltia sabaji has been moved to Hemiancistrus.
There are also a number of undescribed genera. H. landoni possibly represents its own monotypic genus. Also, a group of species called the "H. annectens group" may also represent another undescribed genus that is more closely related to Pterygoplichthys
.
of H. spilomma by Armbruster, they have more recently been considered valid.
The species listed below are part of the unnamed genus of the H. annectens group.
regions of South America
and Panama
, as well as in Pacific coast drainages of Ecuador
. The genus exhibits a large distribution area ranging from the Panama, in Central America
, to southern Brazil
. Hemiancistrus originate from the Guyanas
, the Negro and Orinoco and the southern Amazon
ian tributaries. These fish prefer flowing water habitats of medium to large rivers.
. Also, they have a suckermouth
which they use to cling to rocks in their habitat. They have the characteristic Loricariid omega iris
as well. Like many other catfish, Hemiancistrus have strong pectoral and dorsal fin spines that can be locked outwards as a defense.
Hemiancistrus species are rather small to medium-sized Loricariid species. The largest species of the genus, H. megalopteryx, reaches about 29 centimetres (12 in). These fish also tend to be spotted or uniform in coloration.
fish. Many species are relatively small and attractively colored. H. subviridis is one such example, a bright green fish with yellow spots. However, H. guahiborum is only rarely imported; despite being common in its natural habitat, it is less attractive than H. subviridis, which occurs in the same area.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of small South American armored suckermouth catfishes
Loricariidae
Loricariidae is the largest family of catfish , with almost 700 species and new species being described each year. Loricariids originate from fresh water habitats of Costa Rica, Panama, and tropical and subtropical South America. These fish are noted for the bony plates covering their bodies and...
. The taxonomy
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
of this genus is complex and unclear, and major work has to be done. Many of these fish are popular aquarium
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
fish.
Taxonomy
Hemiancistrus is a genus within the tribeTribe (biology)
In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...
Ancistrini
Ancistrini
Ancistrini is a tribe of catfishes of the family Loricariidae.-Taxonomy:Ancistrini has previously been considered a loricariid subfamily. However, it was realized that the subfamily Hypostominae would be paraphyletic if Ancistrinae continued to be recognized...
of the subfamily Hypostominae
Hypostominae
Hypostominae is a subfamily of catfishes of the family Loricariidae.Studies conducted with representatives of some genera of Hypostominae showed that within thisgroup, the diploid number ranges from 2n = 52 to 2n = 80...
. This genus has long been used as a sort of dump for Loricariid species; fish with unclear relationships have been classified to this genus. As such, this taxon is not monophyletic
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...
. At this point, many undescribed
Undescribed taxon
In taxonomy, an undescribed taxon is a taxon that has been discovered, but not yet formally described and named. The various Nomenclature Codes specify the requirements for a new taxon to be validly described and named. Until such a description has been published, the taxon has no formal or...
species remain.
This genus and the closely related Peckoltia
Peckoltia
Peckoltia is a genus of small South American armored suckermouth catfishes. Many of these fish are popular aquarium fish.-Taxonomy:Peckoltia is a basal genus within the tribe Ancistrini of the subfamily Hypostominae. This genus is paraphyletic...
may be synonymous
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
, as neither genus is supported by synapomorphies
Synapomorphy
In cladistics, a synapomorphy or synapomorphic character is a trait that is shared by two or more taxa and their most recent common ancestor, whose ancestor in turn does not possess the trait. A synapomorphy is thus an apomorphy visible in multiple taxa, where the trait in question originates in...
. Hemiancistrus species differ from other members of the Panaque
Panaque
The genus Panaque contains a small number of small to medium sized South American armoured catfishes that are notable for being among the very few vertebrates that feed extensively on wood. In addition, algae and aufwuchs are an important part of the diet, and they use their rasping teeth to...
clade
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...
lacking the synapomorphies of the other genera and having the dentaries meeting at an angle greater than 120°; in Peckoltia species, the dentaries meet at less than 90° Generally, Peckoltia are considered to be those that have dorsal saddles and bands in the fins, while Heminancistrus have spots and uniform coloration. Many species of Peckoltia may actually belong to Hemiancistrus.
What species belong to this genus has been unclear. Many newer species have been tentatively assigned to Hemiancistrus. Peckoltia sabaji has been moved to Hemiancistrus.
There are also a number of undescribed genera. H. landoni possibly represents its own monotypic genus. Also, a group of species called the "H. annectens group" may also represent another undescribed genus that is more closely related to Pterygoplichthys
Pterygoplichthys
Pterygoplichthys is a genus of the armored catfish family Loricariidae. These fish are commonly known as sailfin armoured catfish or sailfin plecs.-Taxonomy:This genus was described in 1858 by Theodore Nicholas Gill...
.
Species
This species that make up this genus undergoes much change. This list is based on Armbruster. Although the recently described H. micromattos and H. spinosissimus have been considered synonymsSynonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
of H. spilomma by Armbruster, they have more recently been considered valid.
- H. cerrado Souza, Melo, Chamon & Armbruster, 2008
- H. chlorostictus Cardoso and Malabarba, 1999
- H. fuliginosus Cardoso and Malabarba, 1999
- H. guahiborum Werneke, Armbruster, Lujan & Taphorn, 2005
- H. macrops (Lütken, 1874)
- H. medians (Kner, 1854)
- H. megalopteryx Cardoso, 2004
- H. meizospilos Cardoso & da Silva, 2004
- H. micromattos Cardoso and Lucinda 2003
- H. pankimpuju Lujan & Chamon 2008
- H. punctulatus Cardoso & Malabarba, 1999
- H. sabaji (Armbruster, 2003)
- H. spilomma Cardoso & Lucinda, 2003
- H. spinosissimus Cardoso & Lucinda, 2003
- H. votouro Cardoso & da Silva, 2004
- H. snethlageae (SteindachnerFranz SteindachnerFranz Steindachner was an Austrian zoologist.- Work and career :Being interested in natural history, Steindachner took up the study of fossil fishes on the recommendation of his friend Eduard Suess...
, 1911) - H. subviridis Werneke, Sabaj, Lujan & Armbruster, 2005
The species listed below are part of the unnamed genus of the H. annectens group.
- H. annectens (Regan, 1904)
- H. aspidolepis (Günther, 1867)
- H. fugleri (Ovchynnyk, 1971)
- H. holostictus Regan, 1913
- H. maracaiboensis Schultz, 1944
- H. panamensis (EigenmannCarl H. EigenmannCarl H. Eigenmann was an ichthyologist who, along with his wife Rosa Smith Eigenmann, described many of the fishes of North America and South America for the first time....
, 1922) - H. wilsoni Eigenmann, 1918
Distribution and habitat
Hemiancistrus species are found in most cis-AndeanAndes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
regions of South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
and Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...
, as well as in Pacific coast drainages of Ecuador
Ecuador
Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...
. The genus exhibits a large distribution area ranging from the Panama, in Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
, to southern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. Hemiancistrus originate from the Guyanas
Guyanas
Guyana is a country in South America.Guyana, Guayana, or Guiana may also refer to:*Guayana Esequiba, the territory of Guyana claimed by Venezuela*Guayana Region, an administrative region of Venezuela...
, the Negro and Orinoco and the southern Amazon
Amazon River
The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...
ian tributaries. These fish prefer flowing water habitats of medium to large rivers.
Appearance and anatomy
Hemiancistrus are members of the family Loricariidae, the armored suckermouth catfishes. As such, they have armor plating on their body instead of scalesScale (zoology)
In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...
. Also, they have a suckermouth
Suckermouth
In fishes, a suckermouth is a ventrally-oriented mouth adapted for grazing on algae and small organisms that grow on submerged objects....
which they use to cling to rocks in their habitat. They have the characteristic Loricariid omega iris
Loricariidae
Loricariidae is the largest family of catfish , with almost 700 species and new species being described each year. Loricariids originate from fresh water habitats of Costa Rica, Panama, and tropical and subtropical South America. These fish are noted for the bony plates covering their bodies and...
as well. Like many other catfish, Hemiancistrus have strong pectoral and dorsal fin spines that can be locked outwards as a defense.
Hemiancistrus species are rather small to medium-sized Loricariid species. The largest species of the genus, H. megalopteryx, reaches about 29 centimetres (12 in). These fish also tend to be spotted or uniform in coloration.
In the aquarium
Hemiancistrus species are popular aquariumAquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
fish. Many species are relatively small and attractively colored. H. subviridis is one such example, a bright green fish with yellow spots. However, H. guahiborum is only rarely imported; despite being common in its natural habitat, it is less attractive than H. subviridis, which occurs in the same area.