A NEW SPECIES OF THAUMASTOSAURUS (AMPHIBIA: ANURA) FROM THE EOCENE
OF EUROPE
Jean-Claude Rage and Zbyněk Roček, Journal of Vertebrate
Paleontology, 2007, 27(2):329–336
Thaumastosaurus gezei, sp. nov., is described based on the incomplete, holotype skull and an isolated, referred squamosal, both from the so-called "old collections" (late middle or late Eocene in age) from the Phosphorites du Quercy, France. A suite of cranial features, mainly involving sculpture patterns and details of the maxilla and squamosal, differentiates T. gezei from the other three species of Thaumastosaurus. T. gezei appears to be unique among known species of Thaumastosaurus and is unusual among other anurans in having an anteriorly elongate process of the squamosal that extends along the entire dorsal edge of the maxilla, thereby preventing the maxilla from contacting the nasal and contributing to the orbital margin. This derived squamosal configuration, and some other cranial features, suggest a possible relationship between Thaumastosaurus and the South American ceratophryids. If such a relationship proves correct, Thaumastosaurus would be one of the few vertebrate taxa from the Eocene of Europe with South American affinities.