Blue Duck
Hymenolaimus malacorhynchos (J. F. Gmelin, 1789)
Accepted species in Catalogue of Life’s 11 September 2026 base release. This preserves the source classification and available supporting data; it is not a completed species monograph.

Blue Duck (Hymenolaimus malacorhynchos)
Sebastian Doak · CC BY 4.0 · Image sourceProvider-generated thumbnail requested at 320 pixels; no local editing Local WebP display rendition; resized without cropping.
Open encyclopedia reference
The blue duck (Hymenolaimus malacorhynchos) or whio is a member of the duck, goose and swan family, Anatidae and is endemic to New Zealand. It is the only individual species belonging to the genus Hymenolaimus. Its closest relatives are the ducks in the genus Sarkidiornis. First seen and recorded by the British explorer, James Cook in his second voyage to New Zealand, its scientific name was given by the German naturalist, Johann Friedrich Gmelin in 1789 and later George Robert Gray in 1843. There are two subspecies of the blue duck, one in North Island and the other in South Island. Common to both gender, its physical characteristics include yellow iris, a pale grey beak with semicircular flaps and lamellae, dark-slate grey plumage, chestnut flecked breast, dark grey webbed feet, and well developed claws. The male blue duck has a high-pitched whistle, which gave its Māori name Whio, while the female has a low-pitched rattle.
Wikipedia contributors, Blue duck; see linked history · CC BY-SA 4.0 . Plain-text lead excerpt, at most 180 words; no infobox or later sections Retrieved 2026-10-05T01:43:02.496498+00:00. This reference remains separate from the taxonomic record.
Identity & source status
- Scientific name
- Hymenolaimus malacorhynchos (J. F. Gmelin, 1789)
- Name authority
- (J. F. Gmelin, 1789)
- Common name
- Blue Duck
- Rank
- species
- Accepted status
- accepted
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Aves
- Order
- Anseriformes
- Family
- Anatidae
- Genus
- Hymenolaimus
- Extinction status
- Recorded extant
Classification family tree
Nested taxonomic groups from the source. This is not a direct-ancestor chain, a dated evolutionary tree or a phylogenetic reconstruction.
- domainEukaryota (Chatton, 1925) Whittaker & Margulis, 1978
- kingdomAnimalia
- phylumChordata
- subphylumVertebrata
- infraphylumGnathostomata
- parvphylumOsteichthyes
- megaclassTetrapoda
- classAves
- orderAnseriformes
- familyAnatidae Leach, 1820
- genusHymenolaimus G. R. Gray, 1843
- speciesHymenolaimus malacorhynchos (J. F. Gmelin, 1789)
Close classified relatives
No other member of this genus is present in the selected snapshot.
Names & synonyms
Names explicitly linked to this accepted taxon in the source. Synonymy can change with revision.
| Recorded name | Source status |
|---|---|
| Hymenolaimus malacorhynchos malacorhynchos (J. F. Gmelin, 1789) (J. F. Gmelin, 1789) | synonym |
| Hymenolaimus malacorhynchus (J. F. Gmelin, 1789) (J. F. Gmelin, 1789) | synonym |
| Anas malacorhynchos J. F. Gmelin, 1789 J. F. Gmelin, 1789 | synonym |
| Hymenolaimus malacorhynchos hymenolaimus Mathews, 1937 Mathews, 1937 | synonym |
Documented distribution
Source distribution statements, not a complete range map. A listed locality is not necessarily a place of origin.
Source literature & publication evidence
References attached to this source record, including nomenclatural citations where supplied. This is a selected bibliography; abbreviated citations remain in the source’s form.
- https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=175226 Source fields: Taxon.tsv dwc:namePublishedIn, Taxon.tsv dcterms:references
Origins, evidence & remaining research
Name authority and publication references document nomenclature where the source supplies it. They do not establish evolutionary origins or the earliest fossil occurrence.
Specimen-level evidence, morphology, ecological research, phylogenetic studies, a comprehensive bibliography and a located literary passage have not yet been compiled for this record.
Dataset citation & attribution
This exact taxon in ChecklistBank · Catalogue of Life 2026-09-11
Catalogue of Life 2026-09-11; dataset 316321; doi:10.48580/dgz5n. https://creativecommons.org/licenses/by/4.0/ . Retrieved 5 October 2026.
Stable key: col:3NJWW. Classification follows source parent identifiers. English common names may vary by region.