Dekeyseria
Encyclopedia
Dekeyseria is a genus
of catfish
es (order
Siluriformes) of the family
Loricariidae
. It includes six species.
in 1985 by Rapp Py-Daniel. Later, Zonancistrus was described for D. brachyura, D. picta, and D. pulchra. However, this distinction was based on colouration, which is not a useful characteristic in diagnosing genera in loricariids; other genera such as Hypancistrus
and Pseudolithoxus
also exhibit a range of colouration patterns. Though Dekeyseria is not diagnosed by any unique characteristic, it is still a well-diagnosed genus.
, and upper Orinoco
. A. amazonica originates from the Amazon River basin, primarily above Manaus
, Brazil
. D. scaphirhyncha is from the Negro River basin, and D. brachyura and D. picta are from the lower Negro River basin of Brazil. D. niveata inhabits the upper Orinoco River basin in Venezuela
. D. pulchra is distributed in the upper Negro and Orinoco rivers and Canal Casiquiare basin in Brazil, Colombia, and Venezuela.
. Colour pattern is variable with some species brown with some mottling in the fins, and others with a bold pattern of brown bars on a tan background. In brown species, the abdomen is slightly lighter than the sides. In barred species, the head has large tan spots, the spots becoming larger posteriorly until the bars form as separate entities. There are about eight bars in these barred species. However, Dekeyseria species are also able to change their colours quickly, like a chameleon
, to fit their mood or their surroundings.
The species are flattened more than typical Ancistrini
, and the lateral plates have median rows of long, sharp odontode
s forming keels. Odontodes form well-developed rows above and below the keel rows in all individuals. Tentacles are associated with odontodes on the pectoral fin spine and snout, but are shorter than the supporting odontodes (rather than longer, as in Ancistrus
). These fish range in size from 10.0–21 centimetres (3.94–8.27 in) SL
.
Breeding males develop elongated odontodes along the snout margin anterior to the evertible cheek odontodes and on the pectoral fin rays. In some species, the cheek odontodes are extremely long. The brown species appear to have a greater development of the snout odontodes and the barred species a greater development of the pectoral fin spine odontodes.
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 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) of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Loricariidae
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...
. It includes six species.
Species
- Dekeyseria amazonicaDekeyseria amazonicaDekeyseria amazonica is a species of catfish of the family Loricariidae....
- Rapp Py-Daniel, 1985 - Dekeyseria brachyuraDekeyseria brachyuraDekeyseria brachyura is a species of catfish of the family Loricariidae....
- (Kner, 1854) - Dekeyseria niveataDekeyseria niveataDekeyseria niveata is a species of catfish of the family Loricariidae....
- (La Monte, 1929) - Dekeyseria pictaDekeyseria pictaDekeyseria picta is a species of catfish of the family Loricariidae....
- (Kner, 1854) - Dekeyseria pulchraDekeyseria pulchraDekeyseria pulchra is a species of catfish of the family Loricariidae....
- (Steindachner, 1915) - Dekeyseria scaphirhynchaDekeyseria scaphirhynchaDekeyseria scaphirhyncha is a species of catfish of the family Loricariidae....
- (Kner, 1854)
Taxonomy
Dekeyseria was first described with D. amazonica as type speciesBiological type
In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...
in 1985 by Rapp Py-Daniel. Later, Zonancistrus was described for D. brachyura, D. picta, and D. pulchra. However, this distinction was based on colouration, which is not a useful characteristic in diagnosing genera in loricariids; other genera such as Hypancistrus
Hypancistrus
Hypancistrus is a genus of Loricariid catfish originating from the Amazon basin in South America. Unlike many of the other Loricariids, however, some Hypancistrus species are more carnivorous and enjoy meat in their diet...
and Pseudolithoxus
Pseudolithoxus
Pseudolithoxus is a genus of catfishes of the family Loricariidae. It includes five species, P. anthrax, P. dumus, P. kelsorum, P. nicoi, and P. tigris, previously described as the Lasiancistrus anthrax group....
also exhibit a range of colouration patterns. Though Dekeyseria is not diagnosed by any unique characteristic, it is still a well-diagnosed genus.
Distribution
Dekeyseria species are known from the Rio Negro, floodplain lakes of the AmazonAmazon 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...
, and upper Orinoco
Orinoco
The Orinoco is one of the longest rivers in South America at . Its drainage basin, sometimes called the Orinoquia, covers , with 76.3% of it in Venezuela and the remainder in Colombia...
. A. amazonica originates from the Amazon River basin, primarily above Manaus
Manaus
Manaus is a city in Brazil, the capital of the state of Amazonas. It is situated at the confluence of the Negro and Solimões rivers. It is the most populous city of Amazonas, according to the statistics of Brazilian Institute of Geography and Statistics, and is a popular ecotourist destination....
, 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...
. D. scaphirhyncha is from the Negro River basin, and D. brachyura and D. picta are from the lower Negro River basin of Brazil. D. niveata inhabits the upper Orinoco River basin in 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...
. D. pulchra is distributed in the upper Negro and Orinoco rivers and Canal Casiquiare basin in Brazil, Colombia, and Venezuela.
Description
Dekeyseria is an unusual group of fishes that appear similar to LasiancistrusLasiancistrus
Lasiancistrus is a genus of catfishes of the family Loricariidae. It includes six species, L. caucanus, L. guacharote, L. heteracanthus, L. saetiger, L. schomburgkii, and L. tentaculatus.-Taxonomy:...
. Colour pattern is variable with some species brown with some mottling in the fins, and others with a bold pattern of brown bars on a tan background. In brown species, the abdomen is slightly lighter than the sides. In barred species, the head has large tan spots, the spots becoming larger posteriorly until the bars form as separate entities. There are about eight bars in these barred species. However, Dekeyseria species are also able to change their colours quickly, like a chameleon
Chameleon
Chameleons are a distinctive and highly specialized clade of lizards. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a...
, to fit their mood or their surroundings.
The species are flattened more than typical 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...
, and the lateral plates have median rows of long, sharp odontode
Odontode
Odontodes, or dermal teeth, are hard structures found on the external surfaces of animals or near internal openings. They comprise a soft pulp surrounded by dentine and covered by a mineralized substance such as enamel, a structure similar to that of teeth. They generally do not have the same...
s forming keels. Odontodes form well-developed rows above and below the keel rows in all individuals. Tentacles are associated with odontodes on the pectoral fin spine and snout, but are shorter than the supporting odontodes (rather than longer, as in Ancistrus
Ancistrus
Ancistrus is a genus of freshwater fish in the family Loricariidae of order Siluriformes. Fish of this genus are commonly known as the bushynose or bristlenose plecos.-Taxonomy:The type species is Ancistrus cirrhosus...
). These fish range in size from 10.0–21 centimetres (3.94–8.27 in) 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:...
.
Breeding males develop elongated odontodes along the snout margin anterior to the evertible cheek odontodes and on the pectoral fin rays. In some species, the cheek odontodes are extremely long. The brown species appear to have a greater development of the snout odontodes and the barred species a greater development of the pectoral fin spine odontodes.