''Rhyticeros'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of medium to large

hornbill Hornbills (Bucerotidae) are a family (biology), family of bird found in tropical and subtropical Africa, Asia and Melanesia. They are characterized by a long, down-curved bill which is frequently brightly coloured and sometimes has a Casque (an ...

s (family

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

) found in forests from

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

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 loss ...

''. 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 "unispec ...

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 lo ...

. 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 ( "feather") 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, ...

, 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

As generally recognized, the following species belong in the genus ''Rhyticeros'': An undescribed

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

hornbill species from

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

in the

Loyalty Islands The Loyalty Islands Province ( French ''Province des îles Loyauté'') is one of three administrative subdivisions of New Caledonia encompassing the Loyalty Island (french: Îles Loyauté) archipelago in the Pacific, which are located northeast of ...

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

biogeography Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, ...

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 Taxa named by Ludwig Reichenbach