Los Crocodylia (Mesoeucrocodylia, Neosuchia) de la Argentina: estado actual de su registro fósil

BONA, PAULA; BARRIOS, FRANCISCO; GASPARINI, ZULMA

Contribuciones del MACN

Muse Argentino de Ciencias Naturales "Bernardino Rivadavia"

Lugar: Ciudad Autónoma de Buenos Aires; Año: 2016 vol. 6 p. 67 - 83

Herewe present an update of the fossil record of Crocodylia of Argentina, which is representedby Caimaninae alligatorids and Gavialoidea.Less diverse, gavialoids are recorded by a single species, Gryposuchusneogaeus, from the late Miocene of Northeast Argentina. On the other hand, alligatoroids recorded two important moments in its naturalhistory, one at the beginning of the Paleogene (Late Paleocene?Middle Eocene)and the other in the Neogene (Late Miocene). The most ancient record of alligatoroids in South America comesfrom the Early Paleocene of Patagonia. It includes basal forms of caimaninessuch as Necrosuchus ionensis, Eocaiman palaeocenicus, Eocaimancavernensis, and probably a new species of alligatoroid, which provide keymorphological information on the evolutionary and biogeographic history ofthese crocodylians. Anotherimportant moment of the evolutionary history of caimanines is thediversification of the lineage observed during the Miocene. Although there issome isolated cranial material of thisgroup from the Late Miocene of northwestern Argentina, the most abundant anddiverse fossil material comes fromthe northeast, from a level called ?Conglomerado Osífero?. Two genera ofcaimanines are known from this stratigraphic level (Caiman and Mourasuchus)with at least five valid species.