The Anatidae are the biological family of water birds that includes ducks, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted for swimming, floating on the water surface, and in some cases diving in at least shallow water. The family contains around 174 species in 43 genera.
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae, Anseranatidae, and Anatidae, the largest family, which includes over 170 species of waterfowl, among them the ducks, geese, and swans. Most modern species in the order are highly adapted for an aquatic existence at the water surface. With the exception of screamers, males have penises, a trait that has been lost in the Neoaves. Due to their aquatic nature, most species are web-footed.
The smew is a species of duck and is the only living member of the genus Mergellus. Mergellus is a diminutive of Mergus and albellus is from Latin albus "white". This genus is closely related to Mergus and is sometimes included in it, though it might be closer to the goldeneyes (Bucephala). The smew has hybridized with the common goldeneye.
The Anatinae are a subfamily of the family Anatidae. Its surviving members are the dabbling ducks, which feed mainly at the surface rather than by diving. The other members of the Anatinae are the extinct moa-nalo, a young but highly apomorphic lineage derived from the dabbling ducks.
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 split into four separate genera. The genus now contains 31 living species. The name Anas is the Latin for "duck".
Aythya is a genus of diving ducks. It has twelve described species. The name Aythya comes from the Ancient Greek word αυθυια, which may have referred to a sea-dwelling duck or an auklet.
Amphicyon is an extinct genus of large carnivorans belonging to the family Amphicyonidae, subfamily Amphicyoninae, from the Miocene epoch. Members of this family received their vernacular name for possessing bear-like and dog-like features. They ranged over North America, Europe, Asia, and Africa.
Megapaloelodus is an extinct genus of stem flamingo of the family Palaelodidae. Megapaloelodus is primarily known from Miocene America, from South Dakota and Oregon in the north to Argentina in the south, but the species Megapaloelodus goliath was found in Europe. Additionally, one unnamed species was discovered in Miocene sediments from Namibia. Due to a lack of skull material, little can be said about the ecology of Megapaloelodus. Species of this genus are typically larger than those of Palaelodus and appear to have inhabited similar brackish lake environments. Additionally, they may have been capable of "locking" their legs in a standing position.
Eogavialis is an extinct genus of eusuchian crocodylomorph, usually regarded as a gavialoid crocodylian. It superficially resembles Tomistoma schlegelii, the extant false gharial, and consequently material from the genus was originally referred to Tomistoma. Indeed, it was not until 1982 that the name Eogavialis was constructed after it was realised that the specimens were from a more basal form.
Bambolinetta lignitifila is a fossil species of waterfowl from the Late Miocene of Italy, now classified as the sole member of the genus Bambolinetta. First described in 1884 as a typical dabbling duck, it was not revisited until 2014, when a study showed it to be a highly unusual duck species, probably a flightless, wing-propelled diver similar to a penguin.
Spheniscus muizoni is an extinct species of banded penguins that lived during the early Late Miocene in what is now Peru, South America. The species, the earliest member of the extant genus, was described in 2007 by Ursula B. Göhlich based on fossils found in the fossiliferous Pisco Formation of the Pisco Basin, southwestern Peru.
Allgoviachen is an extinct genus of anatid bird from the Late Miocene (Tortonian) Hammerschmiede clay pits of Bavaria, Germany. The genus contains a single species, A. tortonica, known from bones belonging to the left leg.
Thiornis is a fossil genus of Middle Miocene grebe known from a nearly complete specimen from Libros, Spain. Originally classified as a type of moorhen, Thiornis has since been classified as a species of grebe. The overall anatomy of the bird is identical to modern grebes. It contains a single species, T. sociata.
Miobaptus is a fossil genus of grebe that is known from several specimens collected from Czechia and Lake Baikal dating from the Early Miocene to Middle Miocene. Considered to be one of the most primitive genera of grebes, the anatomy of Miobaptus suggests it was less adapted for the aquatic mode of life than modern grebes, but had better flight maneuverability.
Waltonavis is an extinct genus of potentially leptosomiform bird from the Early Eocene London Clay Formation of Essex, United Kingdom. The genus contains two species: W. paraleptosomus and W. danielsi, both known from partial skeletons.
Podiceps solidus is an extinct small species of Upper Miocene to Lower Pliocene grebe from Western Mongolia.
Lavanttalornis is an extinct genus of duck from the Miocene of Austria. The genus is known from a nearly complete specimen preserved across multiple rock slabs and stems from a locality which may represent a possible lagerstätte. It currently includes only a single species, L. hassleri.
Tologuica is an extinct genus of phasianid bird. The remains of both species belonging to the genus, T. aurorae and T. karhui, were discovered in Middle Miocene rocks of the Ööshin Formation, in Mongolia.
Titanoperdix is an extinct monospecific genus of landfowl, belonging to the Phasianidae family. It was related to the modern grey partridge, although it was substantially larger, reaching the size of the modern black grouse. Its fossilized remains were discovered in Early Pleistocene deposits, near Malye Goly, in Irkutsk Oblast, in Eastern Siberia.
