''Rhyticeros'' 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 medium to large

hornbill Hornbills are birds found in tropical and subtropical Africa, Asia and Melanesia of the family Bucerotidae. They are characterized by a long, down-curved bill which is frequently brightly coloured and sometimes has a horny casque on the upper ...

s (family

Bucerotidae Hornbills are birds found in tropical and subtropical Africa, Asia and Melanesia of the family Bucerotidae. They are characterized by a long, down-curved bill which is frequently brightly coloured and sometimes has a horny casque on the upper ...

) found in forests from

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

to the Solomons. They are sometimes included in the genus ''

Aceros The rufous-necked hornbill (''Aceros nipalensis'') is a species of hornbill in Bhutan, northeastern India, especially in Arunachal Pradesh, Indian Subcontinent and Southeast Asia. It is locally extinct in Nepal due to hunting and significant los ...

''. On the other hand, most species generally placed in ''Aceros'' are sometimes moved to ''Rhyticeros'', leaving ''Aceros'' as a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus only containing the

rufous-necked hornbill The rufous-necked hornbill (''Aceros nipalensis'') is a species of hornbill in Bhutan, northeastern India, especially in Arunachal Pradesh, Indian Subcontinent and Southeast Asia. It is locally extinct in Nepal due to hunting and significant los ...

. All species generally placed in ''Rhyticeros'' have relatively low, conspicuously wreathed casques and a mainly dull whitish horn-colored bill. Both sexes have mainly black

plumage Plumage () is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, there can b ...

, but the head and neck of the males are white or rufous. The tail is white except in the black-tailed Sumba hornbill. They have conspicuous inflatable skin on the throat, which is blue in all except the males of the plain-pouched and wreathed hornbills, where it is yellow.

Species

The following six species are placed in the genus: An undescribed

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

hornbill species from

Lifou Lifou () is a communes of France, commune of France in the Loyalty Islands Province of New Caledonia, Pacific Ocean. Geography Lifou is made up of Lifou Island, the largest and most heavily populated of the Loyalty Islands, its smaller neighbou ...

in the

Loyalty Islands Loyalty Islands Province (, ) is one of the three top-level administrative subdivisions of New Caledonia. It encompasses the Loyalty Islands () archipelago in the Pacific Ocean, located northeast of the New Caledonian mainland of Grande Terre. ...

, living until at least some 30,000 years ago, was initially placed in ''Aceros'', but its

biogeography Biogeography is the study of the species distribution, distribution of species and ecosystems in geography, geographic space and through evolutionary history of life, geological time. Organisms and biological community (ecology), communities o ...

places it with the species now in ''Rhyticeros'' (Steadman, 2006).

References

* Kemp, A. C. (2001). Family Bucerotidae (Hornbills). pp. 436–523 in: del Hoyo, J., Elliott, A., & Sargatal, J. eds. (2001). ''Handbook of the Birds of the World.'' Vol. 6. Mousebirds to Hornbills. Lynx Edicions, Barcelona. * Steadman, David William (2006): ''Extinction and Biogeography of Tropical Pacific Birds''. University of Chicago Press. {{Taxonbar, from=Q1081421 Bird genera Birds of Southeast Asia Taxa named by Ludwig Reichenbach