''Corymbophanes'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of armored catfish native to

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 souther ...

where they are only known from Guyana. ''Corymbophanes'' was originally placed in its own

tribe The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English is in the discipline of anthropology. This definition is contested, in part due to confl ...

Corymbophanini, but the first comprehensive molecular phylogenetic analysis of the subfamily

Hypostominae The Hypostominae are a subfamily of catfishes of the family Loricariidae. Most members are restricted to tropical and subtropical South America, but there are also several species (in genera ''Ancistrus'', ''Chaetostoma'', '' Lasiancistrus'', '' ...

found ''Corymbophanes'' to be nested within the tribe

Ancistrini Ancistrini is a tribe of catfishes of the family Loricariidae. Most are restricted to tropical and subtropical South America, but there are also several genus (''Ancistrus'', ''Chaetostoma'', '' Hemiancistrus'' and '' Lasiancistrus'') in southern ...

Taxonomy

''Corymbophanes'' and its type species, ''C. andersoni'', were first described in 1909 by Carl H. Eigenmann. In 2000, they were redescribed along with the description of a new species, ''C. kaiei''. In 2004, the tribe Corymbophanini was erected. ''Corymbophanes'' represents an old lineage as it lacks many of the characteristics of the rest of the subfamily

. This group probably has a

basal Basal or basilar is a term meaning ''base'', ''bottom'', or ''minimum''. Science * Basal (anatomy), an anatomical term of location for features associated with the base of an organism or structure * Basal (medicine), a minimal level that is nec ...

position within the subfamily.

Species

There were previously two recognized species in this genus. A third species was described in a 2020 study. * '' Corymbophanes ameliae'' Lujan, Armbruster, Werneke,

Teixeira Teixeira (, , ) is a Galician-Portuguese Teixeira is a surname of a Portuguese family with toponymic roots whose origin is in the landlord of Teixeira, municipality of Baião in Portugal, belonging to Don Hermígio Mendes de Teixeira, noble in ...

Lovejoy ''Lovejoy'' is a British television comedy-drama mystery series, based on the novels by John Grant under the pen name Jonathan Gash. The show, which ran to 71 episodes over six series, was originally broadcast on BBC1 between 10 January 19 ...

, 2020 * '' Corymbophanes andersoni'' C. H. Eigenmann, 1909 * '' Corymbophanes kaiei'' Armbruster & Sabaj Pérez, 2000

Distribution and habitat

''Corymbophanes'' species originate from the upper Potaro River of the

Essequibo River The Essequibo River (Spanish: ''Río Esequibo'' originally called by Alonso de Ojeda ''Río Dulce'') is the largest river in Guyana, and the largest river between the Orinoco and Amazon. Rising in the Acarai Mountains near the Brazil–Guyana b ...

drainage system. ''C. andersoni'' is only known from the Chenapou Falls of this river. ''C. kaiei'' is only known from the Oung Creek, a small tributary of the Potaro River drainage. Neither of these species are found downstream of the

Kaieteur Falls Kaieteur is the world's largest single drop waterfall. Located on the Potaro River in the Kaieteur National Park, it sits in a section of the Amazon rainforest included in the Potaro-Siparuni region of Guyana. It is 226 metres (741 f ...

. ''Corymbophanes'' species live in swift riffles over gravel and cobble and among submerged logs.

Appearance and anatomy

Like other Loricariids, ''Corymbophanes'' species have plates of armor on their body and a

suckermouth In fish, a suckermouth is a ventrally-oriented (inferior) mouth adapted for grazing on algae and small organisms that grow on submerged objects. All Loricariidae possess a suckermouth as do the cypriniform algae eaters of the genus '' Gyrinocheilu ...

. Small

odontode Odontodes, or dermal teeth, are hard structures found on the external surfaces of animals or near internal openings. They consist of a soft pulp surrounded by dentine and covered by a mineralized substance such as enamel, a structure similar to th ...

s are also present along their body. This genus can be distinguished from all other Loricariids by the presences of a

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal co ...

ridge formed by plates between the

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

and the

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 s ...

, the absence of 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 ...

, as well as the absence of the omega iris that most loricariids possess. ''Corymbophanes'' species do not have evertible cheek plates and do not hypertrophied cheek odontodes which are present in many other loricariid species, which differentiates it from the few species that possess the aforementioned ridge. Species of this genus do not get very large; ''C. andersoni'' does not exceed 8.6 centimetres (3.4 in) and ''C. kaiei'' does not exceed . These fish are dark brown to black with white or cream-colored markings. ''C. kaiei'' has alternating light and dark bands on its caudal fin; also, this species has a dark-colored abdomen with light vermiculations in adults. By contrast, ''C. andersoni'' has no bands on the caudal fin, has no vermiculations, and the abdomen is light-colored.

References

{{Taxonbar, from=Q3766095 Fish of South America Vertebrates of Guyana Hypostominae Catfish genera Taxa named by Carl H. Eigenmann Freshwater fish genera