''Corymbophanes'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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 considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

where they are only known from

Guyana Guyana, officially the Co-operative Republic of Guyana, is a country on the northern coast of South America, part of the historic British West Indies. entry "Guyana" Georgetown, Guyana, Georgetown is the capital of Guyana and is also the co ...

. ''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 use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...

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 southe ...

Taxonomy

''Corymbophanes'' and its type species, ''C. andersoni'', were first described in 1909 by

Carl H. Eigenmann Carl Henry Eigenmann (March 9, 1863 – April 24, 1927) was a German-American ichthyology, ichthyologist of the late nineteenth and early twentieth centuries, who, along with his wife Rosa Smith Eigenmann, and his zoology students is credited wit ...

. 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 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 surname based on the toponym ''Teixeira'', derived from ''teixo'' " yew tree" (Latin ''taxus''). The progenitors of the name were a "Noble Portuguese Marrano family, originally bearing the surname of Samp ...

Lovejoy ''Lovejoy'' is a British television comedy-drama mystery fiction, mystery series, based on the Lovejoy (novel series), novels by John Grant (Lovejoy), John Grant under the pen name Jonathan Gash. The show, which ran to 71 episodes over six ser ...

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

Distribution and habitat

''Corymbophanes'' species originate from the upper

Potaro River The Potaro River is a river in Guyana that runs from Mount Ayanganna area of the Pakaraima Mountains for approximately before flowing into the Essequibo River, Guyana's largest river. The renowned Kaieteur Falls is on the Potaro. Features Ni ...

of the

Essequibo River The Essequibo River (; originally called by Alonso de Ojeda; ) is the largest river in Guyana, and the largest river between the Orinoco and Amazon River, Amazon. Rising in the Acarai Mountains near the Brazil–Guyana border, the Essequibo flows ...

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 Falls is one of the most powerful single-drop waterfalls in the world. It is located on the Potaro River in Kaieteur National Park, central Essequibo Territory, Guyana. It is 226 metres (741 ft) high when measured from its plunge ...

. ''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 t ...

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 The fus ...

ridge formed by plates between the

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

and the

caudal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

, the absence of the

adipose fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only b ...

, 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 Corymbophanes Catfish of South America Fish of Guyana Catfish genera Taxa named by Carl H. Eigenmann Freshwater fish genera