''Palaeospheniscus gracilis'' is a

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 ...

of the

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 ...

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 ...

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 ...

''Palaeospheniscus''. It is the smallest species of its genus, with a height of . Average individuals, thus, were about the size of the

Galapagos penguin The Galápagos penguin (''Spheniscus mendiculus'') is a penguin endemic to the Galápagos Islands, Ecuador. It is the only penguin found north of the equator. Most inhabit Fernandina Island and the west coast of Isabela Island. The cool wate ...

Description

This species was long believed to have first been found in

Early Oligocene The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/ Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattian ...

deposits. However, it seems that the type specimen, a tarsometatarsus, was recovered not from Early Oligocene rocks, but was found on top of them, having been displaced there from a later stratum. The location where the bone was found seems to have been near Cabeza Blanca. At any rate, all later specimens were found in the

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was prece ...

Gaiman Formation The Gaiman Formation ( es, Formación Gaiman), in older literature also referred to as Patagonian Marine Formation ( es, Formación Patagonia Marino, ''Patagoniense''), is a fossiliferous geologic formation of the Peninsula Valdés Basin in the e ...

; those that have locality data are from the area around

Trelew Trelew (, from cy, tref "town" and the name of the founder, Lewis Jones) is a city in the eastern part of the Chubut Province of Argentina. Located in Patagonia, the city is the largest and most populous in the low valley of the Chubut River, wi ...

and Gaiman in

Chubut Province Chubut ( es, Provincia del Chubut, ; cy, Talaith Chubut) is a province in southern Argentina, situated between the 42nd parallel south (the border with Río Negro Province), the 46th parallel south (bordering Santa Cruz Province), the Andes ra ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

.''Palaeospheniscus gracilis''
at

Fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...

.org Some recent researchers have suggested that this species should be considered 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 ''

Palaeospheniscus bergi ''Palaeospheniscus bergi'' is a species of the extinct penguin genus ''Palaeospheniscus''.

''.

Description

References

Further reading