''Rhyticeros'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of medium to large

hornbill 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 mandib ...

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 mandi ...

) 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''. 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. 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 hornbill species from Lifou in the Loyalty Islands, living until at least some 30,000 years ago, was initially placed in ''Aceros'', but its biogeography 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