Peckoltia
Encyclopedia
Peckoltia is a genus
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...

. 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

Peckoltia is a basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...

 genus within the tribe
Tribe (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 is paraphyletic
Paraphyly
A group of taxa is said to be paraphyletic if the group consists of all the descendants of a hypothetical closest common ancestor minus one or more monophyletic groups of descendants...

. At this point, many undescribed species
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...

 remain.

Peckoltia species can be distinguished from most other in the genera in the tribe Ancistrini by having a lateral ridge on the opercle that usually has no 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 and the teeth on their upper jaw (dentary) forming an angle under 90 degrees; while some genera also have an angled dentary, Peckoltia species lack 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...

 of these genera. This genus and the closely related Hemiancistrus
Hemiancistrus
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.-Taxonomy:...

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. Generally, Peckoltia are considered to be those that have dorsal saddles and bands in the fins, while Heminancistrus have spots and uniform coloration. This genus is also similar to 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 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...

except for differences in teeth. Teeth on both jaws are the same size as opposed to different sizes, which is different from Hypancistrus where the upper jaw teeth are larger. Also, the teeth are villiform (brush-shaped) rather than spoon-shaped, in contrast to the Panaque.

The classification of some of the species in this genus has been confused. P. bachi is the senior synonym
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...

 of P. arenaria, P. filicaudata, and P. ucayalensis. This species is quite divergent and may even represent a separate genus; this group has been described twice as such, under the synonyms Peckoltichthys and Sophiancistrus. P. yaravi has been moved to Neblinichthys
Neblinichthys
Neblinichthys is a small genus of catfish of the family Loricariidae. It includes two species, N. pilosus and N. yaravi.-Taxonomy:Neblinichthys was described by Ferraris, Isbrücker, and Nijssen in 1986...

. P. sabaji was arbitrarily placed in this genus (as opposed to Heminacistrus), but may even represent its own genus; later, it was reassigned to Hemiancistrus.

Species

The species that are assigned to this genus are undergoing much flux. Also, many new species have yet to be described. P. sabaji has also been recently described as Hemiancistrus
Hemiancistrus
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.-Taxonomy:...

species, and many of the other species have also been described as such in the past. For example, P. vittata was assigned to Hemiancistrus in the past. As of 2008, Armbruster recognized the following species.
  • Peckoltia bachi
    Peckoltia bachi
    Peckoltia bachi is a species of catfish of the genus Peckoltia.-Distribution and habitat:P. bachi is found throughout the upper Amazon River and its tributaries in Brazil, Colombia, Ecuador, and Peru....

    (Boulenger
    George Albert Boulenger
    George Albert Boulenger FRS was a Belgian-British zoologist who identified over 2000 new animal species, chiefly fish, reptiles and amphibians.-Life:...

    , 1898)
  • Peckoltia braueri (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....

    , 1912)
  • Peckoltia brevis (La Monte, 1935)
  • Peckoltia caenosa Armbruster, 2008
  • Peckoltia cavatica Armbruster & Werneke, 2005
  • Peckoltia compta De Oliveira, Zuanon, Rapp Py-Daniel & Rocha, 2010
  • Peckoltia furcata (Fowler
    Henry Weed Fowler
    Henry Weed Fowler was an American zoologist born in Holmesburg, Pennsylvania.He studied at Stanford University under David Starr Jordan...

    , 1940)
  • Peckoltia lineola Armbruster, 2008
  • Peckoltia multispinis (Holly, 1929)
  • Peckoltia oligospila (Günther
    Albert C. L. G. Günther
    Albert Karl Ludwig Gotthilf Günther FRS, also Albert Charles Lewis Gotthilf Günther , was a German-born British zoologist, ichthyologist, and herpetologist....

    , 1864)
  • Peckoltia vermiculata (Steindachner, 1908)
  • Peckoltia vittata (Steindachner, 1908)

Distribution and habitat

Peckoltia inhabit freshwater
Fresh Water
Fresh Water is the debut album by Australian rock and blues singer Alison McCallum, released in 1972. Rare for an Australian artist at the time, it came in a gatefold sleeve...

 habitats in the 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...

 basin, upper Orinoco, upper Essequibo River
Essequibo River
The Esequibo River is the largest river in Guyana, and the largest river between the Orinoco and Amazon. Rising in the Acarai Mountains near the Brazil-Guyana border, the Essequibo flows to the north for 1,010 km through forest and savanna into the Atlantic Ocean.-Geography:There are countless...

, and also possibly the Maroni River
Maroni River
The Maroni or Marowijne is a river in South America. It originates in the Tumuk Humak Mountains and forms the border between French Guiana and Suriname...

, as well as coastal drainages north of the Amazon to French Guiana
French Guiana
French Guiana is an overseas region of France, consisting of a single overseas department located on the northern Atlantic coast of South America. It has borders with two nations, Brazil to the east and south, and Suriname to the west...

. Three species, P. braueri, P. sabaji, and P. cavatica, are found in the Guiana Shield.

Peckoltia live in shallow, rocky riffles and in quieter water where they hide inside cavities in submerged logs. P. bachi may associate with submerged branches over mud in no to moderate flow.

Appearance and anatomy

Peckoltia are members of the family Loricariidae, the armored suckermouth catfishes. As such, they have armor plating on their body instead of scales
Scale (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, Peckoltia have strong pectoral and dorsal fin spines that can be locked outwards as a defense.

Peckoltia have unmodified teeth and the teeth on their upper jaw form an angle under 90 degrees. Most male Peckoltia have hypertrophied 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 on their body during the breeding season. Except for P. bachi, Peckoltia do not have hypertrophied odontodes on the opercle.

The biggest difference between all the Peckoltia species is coloration. They usually have a saddle-shaped marking on their back. However, P. bachi and P. caenosa are mottled.

Four species, P. braueri, P. caenosa, P. cavatica, and P. vittata, lack spots on their head while the rest have them. P. braueri and P. cavatica have orange bands in the dorsal and caudal fins and have the bones and plates of the head and nape
Nape
The nape is the back of the neck. In technical anatomical/medical terminology, the nape is referred to by the word nucha, which also gives the adjective corresponding to "nape" in English, "nuchal"....

 outlined
in black; in P. caenosa and P. vittata, there are no orange bands and head plates and bones are not outlined. P. caenosa has dark vermiculations on the head and abdomen. P. vittata has saddles or blotches on the head and faint dark spots on the abdomen. P. lineola and P. vermiculata have spots on their head that combine to form vermiculations. In P. lineola the spots form vermiculations that are wider than its pupil
Pupil
The pupil is a hole located in the center of the iris of the eye that allows light to enter the retina. It appears black because most of the light entering the pupil is absorbed by the tissues inside the eye. In humans the pupil is round, but other species, such as some cats, have slit pupils. In...

s, while in P. vermiculata the spots form vermiculations narrower than its pupils; also, the vermiculations radiate from a central point on the head in P. vermiculata, while there is no such pattern in P. lineola.

In the aquarium

True Peckoltia species are fairly rarely exported for the pet trade; species called Peckoltia may actually be Panaque or Hypancistrus species. Peckoltia species are popular aquarium fish as they are small and attractive. They are shy and will spend much of the day hiding.
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