Tachyeres
Encyclopedia
The steamer ducks are a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 (Tachyeres) of duck
Duck
Duck is the common name for a large number of species in the Anatidae family of birds, which also includes swans and geese. The ducks are divided among several subfamilies in the Anatidae family; they do not represent a monophyletic group but a form taxon, since swans and geese are not considered...

s in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Anatidae
Anatidae
Anatidae is the biological family of birds that includes ducks, geese and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica and on most of the world's islands and island groups...

. All of the four species occur in South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

, and all except the Flying Steamer Duck
Flying Steamer Duck
The Flying Steamer Duck, Tachyeres patachonicus, is a steamer duck. It is the most widespread steamer duck, resident in southern Chile and Argentina, Tierra del Fuego and the Falkland Islands. Its plumage is very similar to the other three steamer ducks...

 are flightless; even this one species capable of flight rarely takes to the air. The genus name Tachyeres, "having fast oar
Oar
An oar is an implement used for water-borne propulsion. Oars have a flat blade at one end. Oarsmen grasp the oar at the other end. The difference between oars and paddles are that paddles are held by the paddler, and are not connected with the vessel. Oars generally are connected to the vessel by...

s" or "fast rower", comes from Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...

 ταχυ- "fast" + ἐρέσσω "I row (as with oars)". The common name "steamer ducks" derives because, when swimming fast, they flap their wings into the water as well as using their feet, creating an effect like a paddle steamer
Paddle steamer
A paddle steamer is a steamship or riverboat, powered by a steam engine, using paddle wheels to propel it through the water. In antiquity, Paddle wheelers followed the development of poles, oars and sails, where the first uses were wheelers driven by animals or humans...

.

They are usually placed in the shelduck
Shelduck
The shelducks, genus Tadorna, are a group of large birds in the Tadorninae subfamily of the Anatidae, the biological family that includes the ducks and most duck-like waterfowl such as the geese and swans....

 subfamily Tadorninae. However, mtDNA sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...

 analyses of the cytochrome b
Cytochrome b
Cytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...

 and NADH dehydrogenase
NADH dehydrogenase
NADH dehydrogenase is an enzyme located in the inner mitochondrial membrane that catalyzes the transfer of electrons from NADH to coenzyme Q...

 subunit
Protein subunit
In structural biology, a protein subunit or subunit protein is a single protein molecule that assembles with other protein molecules to form a protein complex: a multimeric or oligomeric protein. Many naturally occurring proteins and enzymes are multimeric...

 2 genes
Gênes
Gênes is the name of a département of the First French Empire in present Italy, named after the city of Genoa. It was formed in 1805, when Napoleon Bonaparte occupied the Republic of Genoa. Its capital was Genoa, and it was divided in the arrondissements of Genoa, Bobbio, Novi Ligure, Tortona and...

 indicate that Tachyeres rather belongs into a distinct clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 of aberrant South American dabbling ducks, which also includes the Brazilian
Brazilian Duck
The Brazilian Teal or Brazilian Duck is the only duck in the genus Amazonetta. It was formerly considered a "perching duck", but more recent analyses indicate that it belongs to a clade of South American dabbling ducks which also includes the Crested Duck, the Bronze-winged Duck, and possibly the...

, the Crested
Crested Duck
The Crested Duck is a species of duck native to South America, the only member of the monotypic genus Lophonetta. It is sometimes included in Anas, but it belongs to a South American clade that diverged early in dabbling duck evolution . There are two subspecies: L...

, and the Bronze-winged Duck
Bronze-winged Duck
The Bronze-winged Duck also known as the Spectacled Duck, is a dabbling duck and the sole member of its genus Speculanas. It is often placed in Anas with most other dabbling ducks, but its closest relative is either the Crested Duck or the Brazilian Duck, which likewise form monotypic genera...

s.

There are four species:
  • Flying Steamer Duck
    Flying Steamer Duck
    The Flying Steamer Duck, Tachyeres patachonicus, is a steamer duck. It is the most widespread steamer duck, resident in southern Chile and Argentina, Tierra del Fuego and the Falkland Islands. Its plumage is very similar to the other three steamer ducks...

     Tachyeres patachonicus
  • Fuegian Steamer Duck Tachyeres pteneres
  • Chubut Steamer Duck Tachyeres leucocephalus
  • Falkland Steamer Duck Tachyeres brachypterus


The Chubut Steamer Duck was only described in 1981.
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