Microglanis
Encyclopedia
Microglanis is a genus of catfish
Catfish
Catfishes 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 heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...

es (order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 Siluriformes) belonging to the family Pseudopimelodidae
Pseudopimelodidae
Pseudopimelodidae is a small family of catfishes. Some of these fish are popular aquarium fish.-Taxonomy:This family was formerly a subfamily of Pimelodidae. Pseudopimelodidae is a monophyletic group. Previously, the superfamily Pseudopimelodoidea is sister to superfamilies Sisoroidea + Loricarioidea...

.

Taxonomy

Microglanis was described in 1912 by Carl H. Eigenmann
Carl H. Eigenmann
Carl 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....

.

This genus is considered 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...

 by a number of autapomorphies
Autapomorphy
In cladistics, an autapomorphy is a distinctive anatomical feature, known as a derived trait, that is unique to a given terminal group. That is, it is found only in one member of a clade, but not found in any others or outgroup taxa, not even those most closely related to the group...

.

Microglanis can be divided into groups of species. For example, the Microglanis parahybae group consist of M. carlae, M. leptostriatus
Microglanis leptostriatus
Microglanis leptostriatus is a species of catfish belonging to the family Pseudopimelodidae. It appears to be entirely restricted to the middle and upper basin of the São Francisco River in Brazil....

, M. garavelloi and M. parahybae.

Distribution

Microglanis has the widest distribution within the family Pseudopimelodidae, with species ranging from the Guianas, Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...

, western slope of the Andes
Andes
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...

 in 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...

 and Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

, to the Río de La Plata
Río de la Plata
The Río de la Plata —sometimes rendered River Plate in British English and the Commonwealth, and occasionally rendered [La] Plata River in other English-speaking countries—is the river and estuary formed by the confluence of the Uruguay River and the Paraná River on the border between Argentina and...

 basin in Argentina. They occur eastward to the Orinoco and 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...

 basins. Microglanis is also present in the eastern coastal rivers of 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...

. The M. parahybae group occurs in coastal rivers from the São Francisco River
São Francisco River
The São Francisco is a river in Brazil. With a length of , it is the longest river that runs entirely in Brazilian territory, and the fourth longest in South America and overall in Brazil...

 southward to the rio Paraíba do Sul
Paraíba do Sul
thumbThe Paraíba do Sul , or simply termed Paraíba, is a river in the south-east of Brazil. It flows 1,137 kilometres west to northeast from its farthest source at the source of the river Paraitinga to the sea near Campos...

, and in the upper Paraná River
Paraná River
The Paraná River is a river in south Central South America, running through Brazil, Paraguay and Argentina for some . It is second in length only to the Amazon River among South American rivers. The name Paraná is an abbreviation of the phrase "para rehe onáva", which comes from the Tupi language...

 basin.

Description

These catfishes are characterized by their small size, which rarely exceeds 70 millimetre
Millimetre
The millimetre is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length....

s (2.8 in
Inch
An inch is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in a foot...

) SL
Fish measurement
Fish measurement refers to the measuring of the length of individual fish and of various parts of their anatomy. These data are used in many areas of ichthyology, including taxonomy and fisheries biology.-Overall length:...

. They never reach over 110 mm (4.3 in) SL. They are also characterized wide mouth (same width as the head), small eyes, and short barbels
Barbel (anatomy)
A barbel on a fish is a slender, whiskerlike tactile organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, sturgeon, the zebrafish and some species of shark...

. They are beautifully colored fishes, with a characteristic light band running across the nape and alternate light and dark blotches over the body.
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