Taxonomy

Abstract: Skeletal remains of penguins from the Eocene La Meseta Formation (Seymour Is− land, Antarctica) constitute the only extensive fossil record of Antarctic Sphenisciformes. No articulated skeletons are known, and almost all fossils occur as single isolated elements. Most of the named species...

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Bibliographic Details
Main Authors: Andrzej Myrcha, Piotr Jadwiszczak
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.586.5354
http://www.polish.polar.pan.pl/ppr27/ppr27-003.pdf
Description
Summary:Abstract: Skeletal remains of penguins from the Eocene La Meseta Formation (Seymour Is− land, Antarctica) constitute the only extensive fossil record of Antarctic Sphenisciformes. No articulated skeletons are known, and almost all fossils occur as single isolated elements. Most of the named species are based on tarsometatarsi (for which the taxonomy was revised in 2002). Here, 694 bones (from the Polish collection) other than tarsometatarsi are reviewed, and allocated to species. They confirm previous conclusions and suggest that ten species grouped in six genera are a minimal reliable estimate of the Eocene Antarctic penguin diver− sity. The species are: Anthropornis grandis, A. nordenskjoeldi, Archaeospheniscus wimani, Delphinornis arctowskii, D. gracilis, D. larseni, Marambiornis exilis, Mesetaornis polaris, Palaeeudyptes gunnari and P. klekowskii. Moreover, diagnoses of four genera (Anthropornis, Archaeospheniscus, Delphinornis and Palaeeudyptes) and two species (P. gunnari and P. klekowskii) are supplemented with additional, non−tarsometatarsal features. Four species of the smallest penguins from the La Meseta Formation (D. arctowskii, D. gracilis, M. exilis and M. polaris) seem to be the youngest taxa within the studied assemblage – their remains come exclusively from the uppermost unit of the formation. All ten recognized species may have co−existed in the Antarctic Peninsula region during the Late Eocene epoch.