Corymbophanes
Encyclopedia
Corymbophanes is a genus
of catfish
(order
Siluriformes) from the family
Loricariidae
. Corymbophanes is the only genus within the tribe
Corymbophanini.
. 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 Hypostominae
. This group probably has a basal
position within the subfamily.
of the Essequibo River
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
. Corymbophanes species live in swift riffles over gravel and cobble and among submerged logs.
. Small odontode
s are also present along their body. This genus can be distinguished from all other Loricariids by the presences of a dorsal
ridge formed by plates between the dorsal fin
and the caudal fin, the absence of the adipose fin, 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 aforementioend 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 6.6 cm (2.6 in). 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.
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...
(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) from 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...
. Corymbophanes is the only 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...
Corymbophanini.
Taxonomy
Corymbophanes and its type species, C. andersoni, were first described in 1909 by Carl H. EigenmannCarl 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....
. 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 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 group probably has 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:...
position within the subfamily.
Distribution and habitat
Corymbophanes species originate from the upper Potaro RiverPotaro River
The Potaro River is a river in Guyana in northern South America.The source of the Potaro River is in the Mount Ayanganna area of the Pakaraima Mountains in the North Rupununi Savannahs...
of the 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...
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
Kaieteur Falls is a high-volume waterfall on the Potaro River in central Guyana, Potaro-Siparuni region. It is located inKaieteur National Park. It is 226 meters high when measured from its plunge over a sandstone and conglomerate cliff to the first break...
. 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 suckermouthSuckermouth
In fishes, a suckermouth is a ventrally-oriented mouth adapted for grazing on algae and small organisms that grow on submerged objects....
. Small 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 are also present along their body. This genus can be distinguished from all other Loricariids by the presences of a dorsal
Dorsum (biology)
In anatomy, the dorsum is the upper side of animals that typically run, fly, or swim in a horizontal position, and the back side of animals that walk upright. In vertebrates the dorsum contains the backbone. The term dorsal refers to anatomical structures that are either situated toward or grow...
ridge formed by plates between the dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
and the caudal fin, the absence of the adipose fin, as well as the absence of the 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...
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 aforementioend 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 6.6 cm (2.6 in). 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.