''Auchenipterichthys'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

driftwood catfish The driftwood catfishes are catfishes of the family Auchenipteridae. The two genera of the former family Ageneiosidae have been placed here, resulting in a grouping of about 125 species in about 22 genera. These fish are found in rivers from Pan ...

es found in

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 ...

Taxonomy

''Auchenipterichthys'' was first described by

Pieter Bleeker Pieter Bleeker (10 July 1819 – 24 January 1878) was a Dutch medical doctor, ichthyologist, and herpetologist. He was famous for the ''Atlas Ichthyologique des Indes Orientales Néêrlandaises'', his monumental work on the fishes of East Asia ...

in 1862, who designated ''A. thoracatus'' (originally described by Kner in 1857 as ''Auchenipterus thoracatus'') as the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

. There are no

derived Derive may refer to: * Derive (computer algebra system), a commercial system made by Texas Instruments * ''Dérive'' (magazine), an Austrian science magazine on urbanism *Dérive, a psychogeographical concept See also * *Derivation (disambiguatio ...

states that is unique to this genus; however, there is no evidence that has been advanced to indicate that this genus is not

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

Species

There are currently four described species in this genus: * '' Auchenipterichthys coracoideus'' ( C. H. Eigenmann & W. R. Allen, 1942) * '' Auchenipterichthys longimanus'' ( Günther, 1864) * '' Auchenipterichthys punctatus'' (

Valenciennes Valenciennes (, also , , ; nl, label=also Dutch, Valencijn; pcd, Valincyinnes or ; la, Valentianae) is a commune in the Nord department, Hauts-de-France, France. It lies on the Scheldt () river. Although the city and region experienced a s ...

, 1840) * '' Auchenipterichthys thoracatus'' ( Kner, 1858)

Description

The eyes of these catfish are large and can be seen from both above and below the fish. The

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

has a long base and at least 18 branched fin rays. The side of the body is decorated with vertical rows of spots above the

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

. The

adipose fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as s ...

is present. The lateral line has an irregular

zigzag A zigzag is a pattern made up of small corners at variable angles, though constant within the zigzag, tracing a path between two parallel lines; it can be described as both jagged and fairly regular. In geometry, this pattern is described as a ...

pattern. The head is flattened anteriorly with a terminal mouth. There are three pairs of thread-like

barbels In fish anatomy and turtle anatomy, a barbel is a slender, whiskerlike sensory organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the zebrafish, the black dragonfish and some ...

, one pair maxillary and two pairs mandibular. The dorsal fin and pectoral fins have large spines; the dorsal fin spine has a lower degree of

serration Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied pr ...

than the pectoral fin spines, which is always serrated strongly on the entire length of both margins. Based on similarities, the species fall into two groups. One group consists of ''A. coracoideus'' and ''A. thoracatus'' which have a

coracoid A coracoid (from Greek κόραξ, ''koraks'', raven) is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is prese ...

covered by a thin layer of integument (allowing the coracoid to be seen from below) and an obliquely truncated

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

. The other includes ''A. longimanus'' and ''A. punctatus'' which has a thick layer of skin covering the coracoid and an emarginate or symmetrical caudal fin. ''A. coracoideus'' typically has 25 or fewer branched anal fin rays, while ''A. thoracatus'' typically has 26 or more branched anal-fin rays. ''A. punctatus'' has a body with variably sized dark spots scattered over the body and the fins, while ''A. longimanus'' does not. Species of ''Auchenipterichthys'' are

sexually dimorphic Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

. Breeding males of ''A. coracoideus'' have an elongated dorsal fin spine. In ''A. longimanus'' and ''A. thoracatus'', serrae on the end of the dorsal fin spine are proportionally longer in breeding males than in juveniles and females. Also, females have an enlarged urogenital opening. Males have their urogenital opening located at the end of a tube bound by

integument In biology, an integument is the tissue surrounding an organism's body or an organ within, such as skin, a husk, shell, germ or rind. Etymology The term is derived from ''integumentum'', which is Latin for "a covering". In a transferred, or ...

to the

anterior Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

margin of the anal fin. The males use their modified anal fin as a means of internal

insemination Insemination is the introduction of sperm into a female’s reproductive system for the purpose of impregnating, also called fertilizing, the female for sexual reproduction. The sperm is introduced into the uterus of a mammal or the oviduct of an ...

; the female can later lay the eggs in isolation.

Ecology

''Auchenipterichthys'' species are

insectivore A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores wer ...

s. ''A. longimanus'' has been reported to feed primarily on terrestrial invertebrates. There is also evidence that ''A. longimanus'' is involved in seed dispersal. ''Auchenipterichthys'' species are also capable of producing sound.

References

{{Taxonbar, from=Q4819408 Auchenipteridae Fish of South America Fish of the Amazon basin Fish of Bolivia Freshwater fish of Brazil Catfish genera Taxa named by Pieter Bleeker