Una nueva Calyptocephalellidae (Anura, Neobatrachia) del Cretácico Superior de la Patagonia, Argentina, con comentarios sobre su posición sistemática

Abstract

The living genus Calyptocephalella is currently represented by the species C. gayi, geographically restricted to Chile, and several extinct Cenozoic species from Argentine Patagonia. In the present paper, a species of Calyptocephalella is described from the Late Cretaceous (Campanian-Maastrichtian) of Río Negro province, Argentina. The new taxon shows a unique combination of apomorphic and plesiomorphic features, and represents the oldest record for the calyptocephalellids. Present analysis indicates that calyptocephalellids are composed by the genera Calyptocephalella, Gigantobatrachus, and Beelzebufo. The genus Gigantobatrachus is revalidated, and a new species of the genus coming from the Paleocene of Patagonia, is described. The genus Beelzebufo is currently represented by the species B. ampinga, from the Latest Cretaceous of Madagascar. Although this taxon was previously referred to Ceratophryidae, present analysis suggests calyptocephalellid affinities for this genus. A brief overview of Late Mesozoic anurans from India sheds doubts about the occurrence of putative Laurasian-like taxa anuran taxa in the Latest Cretaceous of that continent, and most of these specimens are considered as indeterminate neobatrachians or as nearly related to calyptocephalellids, suggesting a wider distribution of this anuran clade during the Mesozoic.