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The helmeted curassow or northern helmeted curassow, (''Pauxi pauxi'') 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. Length in adult birds can vary from . The male, at 3.6 kg (8 lbs), is larger than the female, at 2.6 kg (5.8 lbs). Among standard measurements, the wing chord is , the tail is and the tarsus is .〔''Curassows, Guans and Chachalacas'' by Nigel Hughes. Wildside Books (UK). 2006, ISBN 0905062264〕 Some rare rufous morph female has a black barred and reddish brown plumage. For some time, it also contained the horned curassow taxa as subspecies. Nowadays its southern congener is considered a distinct species ''P. unicornis''. One of the largest birds in its habitat, the helmeted curassow is distributed in the eastern Andes of Venezuela and Colombia. The diet consists mainly of seeds, fruits, insects and small animals. The female lays two cream-colored eggs and incubates them for about 30 days. The helmeted curassow is listed on Appendix II of CITES. Formerly classified as an Vulnerable species by the IUCN,〔BLI (2004)〕 recent research shows that its numbers are decreasing more and more rapidly. It is consequently uplisted to Endangered status in 2008.〔BLI (2008)〕 ==Taxonomy== There are two subspecies: * Mérida helmeted curassow, ''Pauxi pauxi pauxi'' :Cordillera de Mérida into Cordillera Oriental, Colombia :Casque larger, egg-shaped * Perijá helmeted curassow, ''Pauxi pauxi gilliardi'' :Serranía del Perijá :Casque smaller, less bulbous, rather cylindrical in shape. Their evolutionary history is not well researched compared to other curassows. The helmeted curassows probably are a lineage of Late Miocene (Tortonian–Messinian, about 8–7 million years ago) origin. This species' present-day distribution suggests that it became isolated some 6 million years ago as its mountain range uplifted.〔Pereira & Baker (2004)〕 It is not known when gene flow between the subspecies ceased. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Helmeted curassow」の詳細全文を読む スポンサード リンク
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