species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
in the
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 ...
''Siluranodon'' of the
catfish
Catfish (or catfishes; order Siluriformes or Nematognathi) 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 three largest species alive, ...
(
order
Order, ORDER or Orders may refer to:
* Categorization, the process in which ideas and objects are recognized, differentiated, and understood
* Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...
Siluriformes)
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Schilbeidae
Schilbeidae is a family of catfishes native to Africa and Asia. These fish tend to swim in open water.
Schilbid catfishes usually have dorsal fins with a short base and a spine, but ''Parailia'' lack a dorsal fin altogether. Most species also po ...
.
This species is known from the
Nile River
The Nile, , Bohairic , lg, Kiira , Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered the longest rive ...
and the
Chad
Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...
,
Niger
)
, official_languages =
, languages_type = National languagesVolta, and Comoe basins. In the
Sudd
The Sudd (' or ', Dinka language, Dinka: Toc) is a vast swamp in South Sudan, formed by the White Nile's ''Mountain Nile, Baḥr al-Jabal'' section. The Arabic language, Arabic word ' is derived from ' (), meaning "barrier" or "obstruction". The ...
, these fish have been found to occur beneath fringing ''
Eichhornia
''Eichhornia'', commonly called water hyacinths, was a polyphyletic genus of the aquatic flowering plants family Pontederiaceae. Since it was consistently recovered in three independent lineages, it has been sunk into ''Pontederia'', together w ...
''.
Although it has been previously thought that fish of this species lack teeth, it has been found that they have very reduced teeth. As the fish grows, teeth on the upper jaw are lost due to damage, while teeth on the lower jaw are overgrown by the surrounding bone. It has been suggested that this species exhibits
pedomorphosis
Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the physiological, or somatic, development of an organism, typically an animal. Neoteny is found in modern humans compared ...
, that is, they retain many juvenile traits into adulthood. Some of these include an absence of a dorsal fin spine and a reduced number of
rib
In vertebrate anatomy, ribs ( la, costae) are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the ches ...
s. ''S. auritus'' reaches a length of about 17.5
centimetre
330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter.
A centimetre (international spelling) or centimeter (American spellin ...
s (6.9 in) TL.
As adults, ''S. auritus'' are filter-feeders, feeding primarily on
phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'.
Ph ...
and
zooplankton
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...
.
Stomach
The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach i ...
s of fish have been examined to contain zooplankton,
chironomids
The Chironomidae (informally known as chironomids, nonbiting midges, or lake flies) comprise a family of nematoceran flies with a global distribution. They are closely related to the Ceratopogonidae, Simuliidae, and Thaumaleidae. Many species s ...
and
debris
Debris (, ) is rubble, wreckage, ruins, litter and discarded garbage/refuse/trash, scattered remains of something destroyed, or, as in geology, large rock fragments left by a melting glacier, etc. Depending on context, ''debris'' can refer to ...
.
These fish are
oviparous
Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...