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A large therian mammal from the Late Cretaceous of South America.

ABSTRACT: Theria represent an extant clade that comprises placental and marsupial mammals. Here we report on the discovery of a new Late Cretaceous mammal from southern Patagonia, Patagomaia chainko gen. et sp. nov., represented by hindlimb and pelvic elements with unambiguous therian features. We estimate Patagomaia chainko attained a body mass of 14 kg, which is considerably greater than the 5 kg maximum body mass of coeval Laurasian therians. This new discovery demonstrates that Gondwanan therian mammals acquired large body size by the Late Cretaceous, preceding their Laurasian relatives, which remained small-bodied until the beginning of the Cenozoic. Patagomaia supports the view that the Southern Hemisphere was a cradle for the evolution of modern mammalian clades, alongside non-therian extinct groups such as meridiolestidans, gondwanatherians and monotremes.

SUBMITTER: Chimento NR

PROVIDER: S-EPMC10838296 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature

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A large therian mammal from the Late Cretaceous of South America.

Chimento Nicolás R NR Agnolín Federico L FL García-Marsà Jordi J Manabe Makoto M Tsuihiji Takanobu T Novas Fernando E FE

Scientific reports 20240203 1

Theria represent an extant clade that comprises placental and marsupial mammals. Here we report on the discovery of a new Late Cretaceous mammal from southern Patagonia, Patagomaia chainko gen. et sp. nov., represented by hindlimb and pelvic elements with unambiguous therian features. We estimate Patagomaia chainko attained a body mass of 14 kg, which is considerably greater than the 5 kg maximum body mass of coeval Laurasian therians. This new discovery demonstrates that Gondwanan therian mamma ...[more]

PMID: 38310138

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Dataset Information

A large therian mammal from the Late Cretaceous of South America.

Publications

A large therian mammal from the Late Cretaceous of South America.

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