''Palaeeudyptes'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of large

penguin Penguins (order (biology), order List of Sphenisciformes by population, Sphenisciformes , family (biology), family Spheniscidae ) are a group of Water bird, aquatic flightless birds. They live almost exclusively in the Southern Hemisphere: on ...

s, currently containing four accepted

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

. They were probably larger than almost all living penguins, with the smaller species being about the size of an

emperor penguin The emperor penguin (''Aptenodytes forsteri'') is the tallest and heaviest of all living penguin species and is endemic to Antarctica. The male and female are similar in plumage and size, reaching in length and weighing from . Feathers of th ...

, and the largest species, ''Palaeeudyptes klekowskii'', having stood up to tall and weighed up to .

Known species

Of the four species, two (''P. gunnari'' and ''P. klekowskii'') are known from numerous remains found in Middle or Late

Eocene The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...

strata (34 to 50 MYA) of the

La Meseta Formation The La Meseta Formation is a sedimentary sequence deposited during the Eocene. The formation is found on Seymour Island, Antarctica. Description La Meseta Formation lies unconformably on the Cretaceous Lopez de Bertodano Formation. It is an app ...

Seymour Island Seymour Island or Marambio Island, is an island in the chain of 16 major islands around the tip of the Graham Land on the Antarctic Peninsula. Graham Land is the closest part of Antarctica to South America. It lies within the section of the isla ...

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...

. ''P. antarcticus'', the first

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

penguin described, is only really known from a single incomplete

tarsometatarsus The tarsometatarsus is a bone that is only found in the lower leg of birds and some non-avian dinosaurs. It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsus (ankle bones) and meta ...

found in the Late

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

Otekaike Limestone (23 to 28, possibly up to 34 MYA) at

Kakanui The small town of Kakanui lies on the coast of Otago, in New Zealand, fourteen kilometres to the south of Oamaru. The Kakanui River and its estuary divide the township in two. The part of the settlement south of the river, also known as Kakanui ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

, but numerous other bones have been tentatively assigned to the species. The other described New Zealand species, ''P. marplesi'', is known from parts of a skeleton, mainly leg bones, from the Middle or Late

Burnside Mudstone (34 to 40 MYA) at

Burnside, Dunedin Burnside is a mainly industrial suburb of the New Zealand city of Dunedin. It is located at the mouth of a long valley, the Kaikorai Valley, through which flows the Kaikorai Stream. This valley stretches to the northeast for . Burnside is to th ...

. To this species also a number of additional remains have been tentatively assigned. The problem with the indeterminate New Zealand specimens is that they at least in part are intermediate in size between the two species. It may be that ''P. marplesi'' simply evolved into the smaller ''P. antarcticus''. Bones unassignable to species also were found on Seymour Island, but in these cases they seem to be from juvenile individuals or are simply too damaged to be of diagnostic value. In addition, an incomplete right

tibiotarsus The tibiotarsus is the large bone between the femur and the tarsometatarsus in the leg of a bird. It is the fusion of the proximal part of the tarsus with the tibia. A similar structure also occurred in the Mesozoic Heterodontosauridae. These sm ...

(

South Australian Museum The South Australian Museum is a natural history museum and research institution in Adelaide, South Australia, founded in 1856 and owned by the Government of South Australia. It occupies a complex of buildings on North Terrace in the cultu ...

P10862) and one left

humerus The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...

(South Australian Museum P7158) and assignable to this genus were found in the Late Eocene Blanche Point Marls at Witton Bluff near

Adelaide Adelaide ( ) is the capital city of South Australia, the state's largest city and the fifth-most populous city in Australia. "Adelaide" may refer to either Greater Adelaide (including the Adelaide Hills) or the Adelaide city centre. The dem ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. Additionally, an incomplete humerus identified as ''Palaeeudyptes'' was recovered in southernmost Chile, from middle to late Eocene beds of the Río Turbio Formation, near Puerto Natales, south from Torres del Paine National Park.

Phylogeny

The supposed genus '' Wimanornis'', based on two Seymour Island humeri, is apparently a

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

of ''P. gunnari''. The genus is the namesake for the subfamily of primitive penguins, Palaeeudyptinae. Altogether, their

osteological Osteology () is the scientific study of bones, practised by osteologists. A subdiscipline of anatomy, anthropology, and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morphology, funct ...

characteristics seem to have been somewhat less advanced that those of the slightly smaller ''

Archaeospheniscus ''Archaeospheniscus'' is an extinct genus of large penguins. It currently contains three species, known from somewhat fragmentary remains. ''A. wimani'', the smallest species (about the size of a gentoo penguin), was found in Middle or Late Eocen ...

'' and about on par with the gigantic ''

Anthropornis ''Anthropornis'' is a genus of giant penguin that lived 45-33 million years ago, during the Late Eocene and the earliest part of the Oligocene.Myrcha, A., Jadwiszczak, P., Tambussi, C.P., Noriega, J.I., Gazdzicki, A., Tatur, A., and Valle, R.A. ...

''. The exact nature of the relationship of the Palaeeudyptinae to modern penguins is unknown.

References

{{Taxonbar, from=Q3889299 Extinct penguins Eocene birds Oligocene birds Cenozoic Antarctica Cenozoic animals of Oceania Paleogene Oceania Bird genera Prehistoric birds Prehistoric birds of Antarctica Extinct birds of New Zealand Fossil taxa described in 1859 Cenozoic animals of Antarctica

Known species

Phylogeny

See also

References