Horned curassow | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Galliformes |
Family: | Cracidae |
Genus: | Pauxi |
Species: | P. unicornis |
Binomial name | |
Pauxi unicornis Bond, J & Meyer de Schauensee, 1939 | |
Subspecies | |
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Synonyms | |
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The horned curassow (Pauxi unicornis), or southern helmeted curassow, is a species of bird in the family Cracidae found in humid tropical and subtropical forests. It was first described by James Bond and Rodolphe Meyer de Schauensee in 1939 from a specimen collected in Bolivia, and further birds that were described from Peru in 1971 were thought to be a new subspecies. However, the taxonomical position (as subspecies or independent species) of the birds found in Peru in 1971 is unclear. The horned curassow as originally described is endemic to Bolivia. [2] It is a large, predominantly black bird with a distinctive casque on its forehead. It is an uncommon bird with a limited range and is suffering from habitat loss, and the International Union for Conservation of Nature has rated its conservation status as being "critically endangered".
In 1937 while in Bolivia Mr M. A. Carriker found two birds, a male and female, which were in the cracid family. The specimens were subsequently described as a new species by James Bond and Rodolphe Meyer de Schauensee in 1939 and given the scientific name Pauxi unicornis placing it in a genus Pauxi alongside the species P. pauxi. [3] In 1969 another two birds, again a male and female were discovered which resembled those found by Mr. Carriker in 1937. However this time they were found in Peru a long way from the previous P. unicornis discoveries in Bolivia. These Peruvian specimens were described by John Weske and John Terborgh in 1971 as a new subspecies of P. unicornis which they named in honour of Maria Koepcke. [3]
Although the consensus at the time of discovery for P. unicornis to be a species with two subspecies in the genus Pauxi, many different suggestions have been made since. Some suggestions relate to the grouping of species and subspecies within the genus Pauxi. In 1943 Wetmore and Phelps described a new subspecies of the closely related P. pauxi called P. p. gilliardi. When Wetmore and Phelps looked at the three Pauxi forms known at the time, they concluded that P. p. gilliardi was an intermediate form between P. pauxi and P. unicornis. As a result of this they grouped all three forms into a single species with unicornis becoming a subspecies of pauxi. [4] [5] This position was subsequently rejected by Charles Vaurie who argued that P. pauxi and P. unicornis were not conspecific. When Weske and Terborgh discovered the subspecies koepckeae they concluded pauxi and unicornis should be considered separate species. [3] [5] Additional studies by Gastañaga and coauthors in 2011 considered koepckeae to be a wholly distinct species on the basis of a somewhat smaller and more triangular crest and different vocalisations. [6] Gastañaga et al. also coined the name Sira curassow as an English name for the bird in their 2011 paper; [6] the name used by the local inhabitants for the bird is piuri. [7]
Other taxonomic suggestions discuss whether the genus Pauxi should stand alone or be grouped with other genera. In 1965 François Vuilleumier suggested the Pauxi species should be moved into a single genus alongside all the other species in the closely related genera Mitu, Crax and Nothocrax. Just two years later Charles Vaurie opposed this 'lumping' of species and argued that Pauxi, Mitu, Crax and Nothocrax should each be their own genera. [4] Not content with either of these two options Delacour and Amadon suggested that Pauxi and Mitu should indeed be grouped with Crax, but that Nothocrax was distinct enough to be its on genus. Many subsequent authors followed Vaurie, Delacour and Amadon in having Nothocrax as a sister clade to Pauxi, Mitu and Crax, while most have followed Vaurie in having the three other clades as three distinct genera. [3] [5] [8]
Mitochondrial analysis conducted in 2004 suggests that P. unicornis is a sister species to Mitu tuberosum, while the other Pauxi species, P. pauxi, is sister to the combined Mitu and P. unicornis clade. This means the genus Pauxi is not monophyletic but paraphyletic, and to resolve this parsimoniously the genus Pauxi should be sunk into synonymy with Mitu. [8] The paraphyly of Pauxi could be due to incomplete lineage sorting, where a gene tree is inconsistent with its species tree, however this phenomenon should be less prevalent in deep phylogenetic splits (i.e. between genera). Because of this, Pereira et al. conclude incomplete lineage sorting is unlikely to account for the paraphyletic Pauxi genera because, according to their own analysis, Mitu and Pauxi diverged approximately 6.5mya. [8]
The horned curassow is among the largest cracid species. It measures 85 to 95 cm (33 to 37 in) in length. [9] Body mass in large males is up to 3.7 to 3.9 kg (8.2 to 8.6 lb) and only the great curassow is heavier amongst the cracids, although the black curassow and the closely related helmeted curassow are around the same length. [10] Among standard measurements, the wing chord is 38.1 to 40.2 cm (15.0 to 15.8 in), the tail is 31 to 34.8 cm (12.2 to 13.7 in) and the tarsus is 10 to 10.8 cm (3.9 to 4.3 in). [10] It has a distinctive horn or casque on the forehead which projects for over 6 cm. The plumage is generally black, but lacks a blue sheen in primary feathers, and has a white belly, thigh tufts and under-tail coverts. The tail also has white tips. [5]
The horned curassow is threatened by habitat loss. Until 2004 the horned curassow was classified as Vulnerable by the IUCN Red List due to a small and declining population, but was changed to Endangered in 2005 due to an estimated smaller range and greater risk from human activities. [11] In Bolivia the potential habitat of subspecies P. unicornis unicornis may cover an area of 4,000 km2 including the national parks: Amboró, Carrasco and Isiboro Sécure. Despite concentrated fieldwork there are many parts of this potential habitat in which no individuals have been found, for example the most north west 2,000 km2. [11]
The chachalacas, guans and curassows are birds in the family Cracidae. These are species of tropical and subtropical Central and South America. The range of one species, the plain chachalaca, just reaches southernmost parts of Texas in the United States. Two species, the Trinidad piping guan and the rufous-vented chachalaca occur on the islands of Trinidad and Tobago respectively.
Curassows are one of the three major groups of cracid birds. They comprise the largest-bodied species of the cracid family. Three of the four genera are restricted to tropical South America; a single species of Crax ranges north to Mexico. They form a distinct clade which is usually classified as the subfamily Cracinae.
Crax is a genus of curassows in the order Galliformes, a clade of large, heavy-bodied, ground-feeding birds. They are known from tropical South America with one species, the great curassow, ranging northwards through Central America as far as Mexico. The curassows in this genus are noted for their sexual dimorphism; males are more boldly coloured than females and have facial ornamentation such as knobs and wattles. They are also characterised by curly crests and contrastingly-coloured crissa. Crax curassows probably originated as a distinct lineage during the Late Miocene. During the Messinian, the ancestral Crax split into two lineages separated by the Colombian Andes and the Cordillera de Mérida which uplifted at that time. The northern lineage radiated into the great, blue-billed, and yellow-knobbed curassows, while the four southern species evolved as they became separated by the uplifting of various mountain ranges.
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. There is also the peculiar horned guan which is not a true guan, but a very distinct and ancient cracid with no close living relatives.
The great curassow is a large, pheasant-like bird from the Neotropical rainforests, its range extending from eastern Mexico, through Central America to western Colombia and northwestern Ecuador. Male birds are black with curly crests and yellow beaks; females come in three colour morphs, barred, rufous and black. These birds form small groups, foraging mainly on the ground for fruits and arthropods, and the occasional small vertebrate, but they roost and nest in trees. This species is monogamous, the male usually building the rather small nest of leaves in which two eggs are laid. This species is threatened by loss of habitat and hunting, and the International Union for Conservation of Nature has rated its conservation status as "vulnerable".
Maria Koepcke was a German ornithologist known for her work with Neotropical bird species. Koepcke was a well-respected authority in South American ornithology and her work is still referenced today. For her efforts, she is commemorated in the scientific names of four Peruvian bird species and, along with her husband, a Peruvian lizard species.
The helmeted curassow or northern helmeted curassow, is a large terrestrial bird in the family Cracidae found in the subtropical cloud-forest in steep, mountainous regions of western Venezuela and northern Colombia. There are two subspecies found in different mountain ranges. It is a mostly black bird with a white tip to its tail, a red bill and a distinctive grey casque on its forehead. The population of this bird is in decline and the International Union for Conservation of Nature has rated its conservation status as "endangered".
The genus Pauxi consists of the three species of helmeted curassows, terrestrial black fowl with ornamental casque on their heads. All are found in South America.
The Alagoas curassow is a glossy-black, pheasant-like bird. It was formerly found in forests in Northeastern Brazil in what is now the states of Pernambuco and Alagoas, which is the origin of its common name. It is now extinct in the wild; there are about 130 individuals in captivity.
The wattled curassow is a threatened member of the family Cracidae, the curassows, guans, and chachalacas. It is found in remote rainforests in the western Amazon basin in South America. Males have black plumage, except for a white crissum, with curly feathers on the head and red bill ornaments and wattles. Females and juveniles are similar but lack the bill ornamentation and have a reddish-buff crissum area. The wattled curassow is the most ancient lineage of the southern Crax curassows. In captivity, it sometimes hybridises with the blue-billed curassow.
The horned guan is an endangered species in an ancient group of birds of the family Cracidae, which are related to the Australasian megapodes or mound builders (Megapodiidae). It is found in Mexico, Guatemala, and possibly Honduras.
The bare-faced curassow is a species of bird in the family Cracidae, the chachalacas, guans, curassows, etc. It is found in Brazil, Paraguay, and eastern Bolivia, and extreme northeast Argentina, in the cerrado, pantanal, and the southeastern region of the Amazon basin. Its natural habitats are subtropical or tropical dry forest and subtropical or tropical moist lowland forest.
Salvin's curassow is a species of bird in the family Cracidae, the chachalacas, guans, and curassows. It is found in Colombia, Ecuador, and Peru.
The crestless curassow is a species of bird in the family Cracidae, the chachalacas, guans, and curassows. It is found in Brazil, Colombia, Guyana, and Venezuela.
The razor-billed curassow is a species of bird in the family Cracidae, the chachalacas, guans, and curassows. It is found in Bolivia, Brazil, Colombia, and Peru.
The nocturnal curassow is a species of bird in the family Cracidae, the chachalacas, guans, and curassows. It is found in Brazil, Colombia, Ecuador, Peru, and Venezuela.
The Bolivian Yungas is a tropical and subtropical moist broadleaf forest ecoregion in the Yungas of central Bolivia.
The Sira curassow is a species of bird in the family Cracidae. It is found in the Cerros del Sira in central Peru. Its natural habitat is tropical, moist, montane cloud forest.
The Juruá–Purus moist forests (NT0133) is an ecoregion in northwest Brazil in the Amazon biome. The terrain is very flat and soils are poor. The rivers flood annually. There are no roads in the region, and the dense rainforest is relatively intact, although plans to extend the Trans-Amazonian Highway through the region would presumably cause widespread damage to the habitat.