MACNBR   00242
MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
artículos
Título:
The bizarre ?metatherians? Groeberia and Patagonia, late surviving members of gondwanatherian mammals
Autor/es:
NICOLÁS R. CHIMENTO; AGNOLIN, FEDERICO L.; F. E. NOVAS
Revista:
Historical Biology An International Journal of Paleobiology
Editorial:
Taylor & Francis
Referencias:
Año: 2014
ISSN:
0891-2963
Resumen:
Cenozoic
mammalian faunas from South America contrast with those of the other continents by the great
diversification of metatherian mammals. Among the later, a wide range of
morphological disparity have been reported, and several bizarre mammals
have been assigned to such clade, based mainly on biogeographical grounds.
Outstanding examples of bizarre mammals referred to as Metatheria are the
Eocene Groeberia and the Miocene Patagonia. Recent discoveries indicate
that South
America
possessed a more diverse faunal composition than previously thought, and
it became evident that many
Mesozoic holdovers (e.g. australosphenidans, gondwanatherians and
dryolestoids) surpassed the K/T boundary, thus forming part of the
Cenozoic faunas. The Cenozoic taxa Patagonia and Groeberia exhibit several
similarities with the Gonwanatheria, including rodent-like jaws with
enlarged incisives, molariform cheek-teeth, anteriorly extended masseteric
fossa and palinal mastication among other features. The inclusion of
Gondwanatheria, Patagonia and Groeberia within an abarcative phylogenetic analysis resulted
in close phylogenetic relationships among these taxa. Such hypothesis
indicates
that Cretaceous relics in the Cenozoic of South America were more
diversified than previously thought.