Horned Guan
Encyclopedia
The Horned Guan, Oreophasis derbianus is a large, approximately 85 cm long, turkey
-like bird with glossed black upperparts plumage, red legs, white iris
, yellow bill
and a red horn on top of head. The breast and upper belly are white, and its long tail feathers are black with white band near base. Both sexes are similar. The young is duller with smaller horn, and has brown tail and wings.
The only member in monotypic genus
Oreophasis, the Horned Guan is distributed in humid mountain forests of southeast Mexico
-(Chiapas
) and Guatemala
of Central America
. It is found in altitude up to 3,350 metres. Its diet consists mainly of fruits, green leaves and invertebrates. The female usually lays up to two eggs.
The Horned Guan is not a true guan
, but merely resembles these birds most in overall shape and color, whereas the horn is more reminiscent of the helmeted curassow
s. In fact, this species
is the only survivor of a very ancient lineage of cracid
s that has been evolving
independently from all other living members of this family
for at least 20, possibly as much as 40 million years.
Although it does not have any really close relatives among living cracids, the true guans are apparently most distant. Given that the basal
relationships of the living cracids are not well resolved, the Horned Guan is often placed into a distinct subfamily, the Oreophasinae. Alternatively, it might be included in a large Cracinae with curassow
s and chachalaca
s (Pereira et al. 2002)
Due to ongoing habitat loss, small population size, limited range and hunting in some areas, the Horned Guan is evaluated as Endangered on the IUCN Red List
of Threatened Species. It is listed on Appendix I of CITES.
Turkey (bird)
A turkey is a large bird in the genus Meleagris. One species, Meleagris gallopavo, commonly known as the Wild Turkey, is native to the forests of North America. The domestic turkey is a descendant of this species...
-like bird with glossed black upperparts plumage, red legs, white iris
Iris (anatomy)
The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupils and thus the amount of light reaching the retina. "Eye color" is the color of the iris, which can be green, blue, or brown. In some cases it can be hazel , grey, violet, or even pink...
, yellow bill
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
and a red horn on top of head. The breast and upper belly are white, and its long tail feathers are black with white band near base. Both sexes are similar. The young is duller with smaller horn, and has brown tail and wings.
The only member in monotypic 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...
Oreophasis, the Horned Guan is distributed in humid mountain forests of southeast Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
-(Chiapas
Chiapas
Chiapas officially Estado Libre y Soberano de Chiapas is one of the 31 states that, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 118 municipalities and its capital city is Tuxtla Gutierrez. Other important cites in Chiapas include San Cristóbal de las...
) and Guatemala
Guatemala
Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast...
of Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
. It is found in altitude up to 3,350 metres. Its diet consists mainly of fruits, green leaves and invertebrates. The female usually lays up to two eggs.
The Horned Guan is not a true guan
Guan (bird)
The guans are a number of bird genera which make up the largest group in the family Cracidae. They are found mainly in northern South America, southern Central America, and a few adjacent Caribbean islands...
, but merely resembles these birds most in overall shape and color, whereas the horn is more reminiscent of the helmeted curassow
Helmeted Curassow
The Helmeted Curassow or Northern Helmeted Curassow, is a large terrestrial black curassow with a small head, large bluish grey casque on forehead, red bill, white-tipped tail feathers, greenish glossed mantle and breast feathers, and white below. Both sexes are similar...
s. In fact, this species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
is the only survivor of a very ancient lineage of cracid
Cracidae
The chachalacas, guans and curassows are birds in the family Cracidae.These are species of tropical and subtropical Central and South America. One species, the Plain Chachalaca, just reaches southernmost Texas in the USA...
s that has been evolving
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
independently from all other living members of this 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...
for at least 20, possibly as much as 40 million years.
Although it does not have any really close relatives among living cracids, the true guans are apparently most distant. Given that the 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:...
relationships of the living cracids are not well resolved, the Horned Guan is often placed into a distinct subfamily, the Oreophasinae. Alternatively, it might be included in a large Cracinae with curassow
Curassow
Curassows are one of the three major groups of cracid birds. Three of the four genera are restricted to tropical South America; a single species of Crax ranges north to Mexico...
s and chachalaca
Chachalaca
Chachalacas are mainly brown birds from the genus Ortalis. These cracids are found in wooded habitats in far southern United States , Mexico, and Central and South America. They are social, can be very noisy and often remain fairly common even near humans, as their relatively small size makes them...
s (Pereira et al. 2002)
Due to ongoing habitat loss, small population size, limited range and hunting in some areas, the Horned Guan is evaluated as Endangered on the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
of Threatened Species. It is listed on Appendix I of CITES.
External links
- BirdLife Species Factsheet
- Horned Guan photo, Article Aventuras Naturales
- Horned Guan image; Article (Oil paintings)
- Stamps (for MexicoMexicoThe United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
, three types) - Horned Guan photo gallery VIREO
- Horned Guan videos on the Internet Bird Collection
