Editing Blue duck (section)

{{short description|Species of duck endemic to New Zealand}}
{{About|the bird native to New Zealand|other uses|Blue Duck (disambiguation)}}
{{Redirect|Whio||WHIO (disambiguation){{!}}WHIO}}
{{Use dmy dates|date=December 2019}}
{{Use New Zealand English|date=December 2016}}
{{speciesbox
| name = Blue duck
| status = EN
| status_system = IUCN3.1
| status_ref = <ref name=iucn>{{cite iucn |author=BirdLife International |year=2022 |title=''Hymenolaimus malacorhynchos'' |page=e.T22680121A214275489 |doi=10.2305/IUCN.UK.2022-2.RLTS.T22680121A214275489.en}}</ref>
| image = Whio (Blue Duck) at Staglands, Akatarawa, New Zealand.jpg
| image_caption = Blue duck at Staglands, [[Akatarawa Valley]]
| genus = Hymenolaimus
| parent_authority = [[George Robert Gray|G.R. Gray]], 1843
| species = malacorhynchos
| authority = ([[Johann Friedrich Gmelin|Gmelin, JF]], 1789)
| subdivision_ranks = Subspecies
| synonyms = ''Anas malacorhynchus'' ([[protonym]])
| subdivision = See text
| range_map = Hymenolaimus malacorhynchos - distribution map.svg
| range_map_caption = {{leftlegend|#008100|Extant}}{{leftlegend|#DBD56E|Probable original distribution where the blue duck is extinct}}
}}

The '''blue duck''' ('''''Hymenolaimus malacorhynchos''''') or '''whio''' is a member of the [[duck]], [[goose]] and [[swan]] [[family (biology)|family]] [[Anatidae]] endemic to New Zealand. It is the only member of the genus '''''Hymenolaimus'''''. Its exact taxonomic status is still unresolved, but it appears to be most closely related to the tribe [[Anatini]], the dabbling ducks.

The whio is depicted on the reverse side of the [[New Zealand ten-dollar note|New Zealand $10 banknote]].