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 form taxon; they do not represent a monophyletic group, since swans and geese are not considered ducks. Ducks are mostly aquatic birds, and may be found in both fresh water and sea water.
Grebes are aquatic diving birds in the order Podicipediformes. Grebes are widely distributed freshwater birds, with some species also found in marine habitats during migration and winter. Most grebes fly, although some flightless species exist, most notably in stable lakes. The order contains a single family, the Podicipedidae, which includes 22 species in six extant genera.
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.
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.
The white-headed duck is a small diving duck some 45 cm (18 in) long. The male has a white head with black crown, a blue bill, and reddish-grey plumage. The female has a dark bill and rather duller colouring. Its breeding habitat is lakes with open water and dense vegetation at the margin. It dives under water and feeds on aquatic vegetation as well as some animal matter. It is more likely to swim away from a perceived threat than to fly. This duck is known from Spain, North Africa, Western Asia and Central Asia. Populations are declining, mostly due to loss of habitat and pollution, and the International Union for Conservation of Nature has rated the bird's status as "endangered".
Ostriches are large flightless birds. They are the heaviest and largest living birds, with adult common ostriches weighing anywhere between 63.5-145 kilograms and laying the largest eggs of any living land animal. With the ability to run at 70 km/h (43.5 mph), they are the fastest birds on land. They are farmed worldwide, with significant industries in the Philippines and in Namibia. Ostrich leather is a lucrative commodity, and the large feathers are used as plumes for the decoration of ceremonial headgear. Ostrich eggs have been used by humans for millennia.
Chendytes lawi or Laws Duck is an extinct, goose-sized flightless marine duck, once common on the California coast, the California Channel Islands, and possibly southern Oregon. It lived in the Pleistocene and survived into the Holocene. It appears to have gone extinct at about 450–250 BCE. The youngest direct radiocarbon date from a Chendytes bone fragment dates to 770–400 BCE and was found in an archeological site in Ventura County. Its remains have been found in fossil deposits and in early coastal archeological sites. Archeological data from coastal California show a record of human exploitation of Chendytes lawi for at least 8,000 years. It was probably driven to extinction by hunting, animal predation, and loss of habitat. Chendytes bones have been identified in archaeological assemblages from 14 coastal sites, including two on San Miguel Island and 12 in mainland localities. Hundreds of Chendytes bones and egg shells found in Pleistocene deposits on San Miguel Island have been interpreted as evidence that some of these island fossil localities were nesting colonies, one of which Guthrie dated to about 12,000 14C years. There is nothing in the North American archaeological record indicating a span of exploitation for any megafaunal genus remotely as long as that of Chendytes.
Dyrosaurus is a genus of extinct crocodylomorph that lived during the early Eocene. The name Dyrosaurus comes from sauros (σαῦρος) the Greek for lizard or reptile, and Dyr for Djebel Dyr (mountain) close to where the type species was discovered. It was a large reptile with an estimated body length of 6.5 metres (21 ft).
Eileanchelys is an extinct genus of primitive turtle from the Middle Jurassic (Bathonian) period some 164 million years ago of Britain. Only one species is recorded, Eileanchelys waldmani. It is the best-represented turtle from the Middle Jurassic, because of the amount of specimens that can be assigned to it. The turtle is also one of the oldest turtles ever found to be aquatic, and might represent a milestone in turtle evolution.
Mystiornis is an extinct genus of bird which existed in what is now western Siberia, Russia during the early Cretaceous period. It is known from an isolated metatarsus found in the Shestakovo-1 locality of southern Western Siberia. It was named by Evgeny N. Kurochkin, Nikita V. Zelenkov, Alexandr O. Averianov and Sergei V. Leshchinskiy in 2011, and the type species is Mystiornis cyrili. While most recent studies place it as an Enantiornithine, specifically an Avisaurid, the authors note that the placement in both groups is tentative and further material will be required to make a firm decision on placement due to the unusual features of the existing material.
Jaxtasuchus is an extinct genus of armored doswelliid archosauriform reptile known from the Middle Triassic of the Erfurt Formation in Germany. The type species, Jaxtasuchus salomoni, was named in 2013 on the basis of several incomplete skeletons and other isolated remains. Like other doswelliids, members of the genus were heavily armored, with four longitudinal rows of bony plates called osteoderms covering the body. Jaxtasuchus is the first doswelliid known from Europe and is most closely related to Doswellia from the Late Triassic of the eastern United States. However, it was not as specialized as Doswellia, retaining several generalized archosauriform characteristics and having less armor. Jaxtasuchus fossils have been found in aquatic mudstones alongside fossils of temnospondyl amphibians, crustaceans, and mollusks, suggesting that Jaxtasuchus was semiaquatic like modern crocodilians.
Parabohaiornis is an extinct genus of bohaiornithid enantiornithean dinosaur known from the Early Cretaceous of Liaoning Province, northeastern China. It contains a single species, Parabohaiornis martini.
Longusunguis is an extinct genus of bohaiornithid enantiornithean dinosaur known from the Early Cretaceous of Liaoning Province, northeastern China. It contains a single species, Longusunguis kurochkini.
Sinanas is a genus of prehistoric duck that lived during the middle Miocene. The single known species is Sinanas diatomas. Fossils of the species have been recovered from the Shandong Province of China. Taxonomists are uncertain as to its affinities to modern waterfowl.
Chenoanas is an extinct genus of duck from Eurasia. It is known from three species, C. sansaniensis, C. deserta and C. asiatica. The latter two species were named by Nikita Zelenkov.
Parapengornis is an extinct genus of enantiornithine bird from the Lower Cretaceous of what is now China. The holotype specimen was discovered in the Jiufotang Formation near Lingyuan, western Liaoning province, and was catalogued as IVPP V18687. The nearly complete, articulated specimen is preserved on a slab and has impressions of pennaceous feathers. Only parts of the sternum, the left hand, and right foot are missing. In 2015, it became the basis of the new genus and species Parapengornis eurycaudatus, named by the Chinese palaeontologists Han Hu, Jingmai K. O’Connor, and Zhonghe Zhou. The generic name consists of the Latin word para and the name of the related genus Pengornis, indicating their close relationship. The name Pengornis is itself derived from "Peng", a mythological bird from Chinese folklore, and ornis, which means bird in Greek. The specific name is derived from the Latin words eury, meaning broad, and caudatus, meaning tail, in reference to the broad and expanded pygostyle. A nearly complete specimen formerly assigned to Pengornis was also reassigned to Parapengornis by these authors.
IberospinusIPA:[aɪbiːʌroʊs̠piːnʊs̠] or IPA:[aɪbiːʌroʊs̠paɪnʌs̠] is an extinct genus of spinosaurid dinosaur from the Early Cretaceous (Barremian) Papo Seco Formation of Portugal. The genus contains a single species, I. natarioi, known from several assorted bones belonging to one individual. Iberospinus represents one of four known spinosaurid taxa from the Iberian Peninsula, the others being Vallibonavenatrix, Camarillasaurus and Protathlitis. It is important for its implications of the geographical origin of Spinosauridae and the suggested presence of an at least semi-aquatic lifestyle early in the evolution of this clade.
Annakacygna is a genus of flightless marine swan from the Miocene of Japan. Named in 2022, Annakacygna displays a series of unique adaptations setting it apart from any other known swan, including a filter feeding lifestyle, a highly mobile tail and wings that likely formed a cradle for their hatchlings in a fashion similar to modern mute swans. Additionally, it may have used both wings and tail as a form of display. All of these traits combined have led the researchers working on it to dub it "the ultimate bird". Two species are known, A. hajimei, which was approximately the size of a black swan, and A. yoshiiensis which exceeded the mute swan in both size and weight. The describing authors proposed the vernacular name Annaka short-winged swan for the genus.
Caerulonettion is an extinct genus of anatid birds from the Miocene Epoch of Europe. The genus contains a single species, C. natator, known from various limb and girdle bones. The Caerulonettion fossil material was originally assigned to various other anatid genera before being recognized as a distinct genus.
