Archaeospheniscus is an extinct 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...

 of large penguin

Penguin

Penguins are a group of aquatic, flightless birds living almost exclusively in the southern hemisphere, especially in Antarctica. Highly adapted for life in the water, penguins have countershaded dark and white plumage, and their wings have become flippers...

s. It currently contains three species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

, known from somewhat fragmentary remains. A. wimani, the smallest species (about the size of a Gentoo Penguin

Gentoo penguin

The Gentoo Penguin , Pygoscelis papua, is easily recognized by the wide white stripe extending like a bonnet across the top of its head and its bright orange-red bill. The gentoo penguin has pale whitish-pink webbed feet and a fairly long tail - the most prominent tail of all penguins. Chicks have...

), was found in Middle or Late Eocene

Eocene

The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 strata (34-50 MYA) of the La Meseta Formation on Seymour Island

Seymour Island

Seymour 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 closer to continental land mass than any other part of that Antarctica. It lies within the section of the island chain that resides off the west side of the...

, Antarctica, whereas the other two, about the size of a modern Emperor Penguin

Emperor Penguin

The Emperor Penguin 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 height and weighing anywhere from . The dorsal side and head are black and sharply delineated from the white belly,...

, are known from bones recovered from the Late Oligocene

Oligocene

The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...

 Kokoamu Greensand Formation (27-28 MYA) at Duntroon, New Zealand

Duntroon, New Zealand

Duntroon is a small farming town in the Waitaki District of New Zealand's South Island. Although traditionally considered a North Otago town, it is presently officially located within the farthest southern reaches of Canterbury...

.

The genus is one of the earliest known primitive penguins. Its humerus

Humerus

The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....

 is still very slender, between the form seen in ordinary bird wings and the thickened condition found in modern penguins. On the other hand, the tarsometatarsus

Tarsometatarsus

The tarsometatarsus is a bone that is found in the lower leg of certain tetrapods, namely birds.It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsal and metatarsal bones...

 shows a peculiar mix of characters found in modern and primitive forms. Whether this signifies that the genus is an ancestor of modern taxa or represents a case of parallel evolution

Parallel evolution

Parallel evolution is the development of a similar trait in related, but distinct, species descending from the same ancestor, but from different clades.-Parallel vs...

 is unknown.

Species

• Lowe's Penguin
  Archaeospheniscus lowei
  Lowe's Penguin is the type species of the extinct penguin genus Archaeospheniscus. It stood approximately 85-115 cm high, between a modern King Penguin and an Emperor Penguin in size...
  
   (Archaeospheniscus lowei)
• Lopdell's Penguin
  Archaeospheniscus lopdelli
  Lopdell's Penguin was the largest species of the extinct penguin genus Archaeospheniscus, standing about 90-120 cm high, or somewhat less than the extant Emperor Penguin. It is only known from bones of a single individual which was found in the Late Oligocene Kokoamu Greensand Formation at...
  
   (Archaeospheniscus lopdelli)
• Archaeospheniscus wimani
  Archaeospheniscus wimani
  Archaeospheniscus wimani is an extinct species of penguin. It was the smallest species of the genus Archaeospheniscus, being approximately 75-85 cm high, or about the size of a Gentoo Penguin. It is also the oldest known species of its genus, as its remains were found in Middle or Late Eocene...