South America

The South American continent is, thus far, home to only one site for Early Cretaceous mammals. The site, near Zapala in Neuquen Province, Argentina (figure 2.7), is in the La Amarga Formation, of Hauterivian or Hauterivian-Barremian age (Bonaparte, 1986a; Rougier et al., 1992). Only a single taxon, Vincelestes neuquenianus, is known from the site, but it is a highly significant occurrence: Vincelestes is represented by unusually complete materials, including 17 dentaries, six nearly complete skulls, and various postcrania (see, e.g., Bonaparte and Rougier, 1987; Rougier et al., 1992; Rougier, 1993). Vincelestes is of special interest because it is so completely known and because it appears to be a proximal relative of boreosphenidan mammals (see chapter 10). One other occurrence in the Early Cretaceous of South America should be mentioned here for the sake of completeness. Several teeth from the Lower Cretaceous (Albian) Itapecuru Formation near Itapecuru-Mirim, Maranhno, Brazil, were described as a "triconodont," Candidodon itapecuruense (see Carvalho and Campos, 1988). Closer study revealed that the teeth belong to a notosuchian crocodile with heterodont dentition (Carvalho, 1994).

Footprints attributed to a mammal have been reported from rocks of unspecified age at Nanhuel-Huapi, Argentina. The site, not shown here, is included on a map with sites of Cretaceous age by Leonardi (1994: 11).

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