Un anuro gigante del Mioceno de Patagonia

Abstract

Á new genus and species of a Leptodactyl, Gigantobatrachus parodii Cas, is described [rom the Friasean (middle Mioceno) of Laguna Blanca and Rio Guenguel, morih to Lago Buenos Aires, Province of Santa Cruz, Argentine. The genus is very close to Calyptocephalella and Eophractus but considerably larger (trunk more than 300 mm), surpassing in this character all the known anu ran, and can only be compared with the african Gigantorana goliatk, The autor remarks that among anura wilbh maxilary teeth and cephalic shield, there are only Pelobatids and some genera of Leptodactylids and Hilids, apart from Brachycephalus, This latter genus and the Hylids are eliminated because of their small size and the Pelobatids becansq of their skull morphology. Among th* Leptodectylids the closest affinities are with Calyptocephalella and the Ceratophrynids, both with “ossil representatives in Argentine; from this subfamily it diflers in the orbital height. From Eophractus it differs in the number of maxillary and premaxillary teeth and io the vertebral morphology, It approaches very closely to Calyptocephalella, a genus from which it can be separated fundementally only by the dental formula. With respect to this problem, the autor has made dental counts in different species of Leptodactylids, Hylids and Pseudids.