''Anas chathamica'', the Chatham duck or Chatham Islands duck, is an extinct

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

duck Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a fo ...

, formerly placed in 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 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 ...

''Pachyanas'', which once lived in New Zealand's

Chatham Islands The Chatham Islands ( ) ( Moriori: ''Rēkohu'', 'Misty Sun'; mi, Wharekauri) are an archipelago in the Pacific Ocean about east of New Zealand's South Island. They are administered as part of New Zealand. The archipelago consists of about t ...

in the south-west

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

. It was described by

Walter Oliver Walter Reginald Brook Oliver (7 September 1883 – 16 May 1957) was a New Zealand naturalist, ornithologist, malacologist, and museum curator. Biography Born in Launceston, Tasmania, Oliver emigrated with his family to New Zealand in 1896, ...

(as a "stoutly built duck") from bird bones in the collection of the Canterbury Museum in 1955 in the second edition of his work ''New Zealand Birds''. Recently, analysis of mitochondrial DNA extracted from

subfossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

remains showed that the Chatham duck was not, in fact, closely related to

shelduck The shelducks, most species of which are found in the genus ''Tadorna'' (except for the Radjah shelduck, which is now found in its own monotypic genus ''Radjah''), are a group of large birds in the Tadorninae subfamily of the Anatidae, the biolog ...

s but instead belongs in the genus

Anas ''Anas'' is a genus of dabbling ducks. It includes the pintails, most teals, and the mallard and its close relatives. It formerly included additional species but following the publication of a molecular phylogenetic study in 2009 the genus was s ...

: the dabbling ducks. Its closest living relatives appear to be the

Auckland teal The Auckland teal (''Anas aucklandica''), also known as Auckland Islands teal or brown teal, is a species of dabbling duck of the genus ''Anas'' that is endemic to Auckland Islands south of New Zealand. The species was once found throughout the A ...

, the

Campbell teal The Campbell teal or Campbell Island teal (''Anas nesiotis'') is a small, flightless, nocturnal species of dabbling duck of the genus ''Anas'' endemic to the Campbell Island group of New Zealand. It is sometimes considered conspecific with the ...

and the

brown teal The brown teal (''Anas chlorotis''; mi, pāteke) is a species of dabbling duck of the genus '' Anas'' native to New Zealand. For many years it had been considered to be conspecific with the flightless Auckland and Campbell teals in ''Anas auck ...

from New Zealand. Some authors have suggested that the Chatham duck was

flightless Flightless birds are birds that through evolution lost the ability to fly. There are over 60 extant species, including the well known ratites ( ostriches, emu, cassowaries, rheas, and kiwi) and penguins. The smallest flightless bird is ...

; however, comparison of Chatham duck wing bones with those from living ducks indicates no disproportional reduction in wing length. The Chatham duck likely became extinct in about the 16th century because of hunting by humans.

References

External links

Chatham Island Duck '' Pachyanas chathamica'' by Paul Martinson.
Artwork produced for the book ''Extinct Birds of New Zealand'', by Alan Tennyson, Te Papa Press, Wellington, 2006 Ducks Extinct flightless birds Extinct birds of the Chatham Islands Bird extinctions since 1500 Birds described in 1955 Fossil taxa described in 1955 Anatinae {{duck-stub