From toad to frog, a CT-based reconsideration of <i>Bufo servatus</i>, an Eocene anuran mummy from Quercy (France)

In the 19th century, natural mummies of amphibians were discovered in Quercy Phosphorites. The specific collection site was never formally reported, which hampers precise dating these specimens. Still, name Bufo servatus erected based on external morphology one mummified A tomography a similarly preserved specimen revealed skeleton, soft tissues and gut contents. We analyze here holotype using CT-scanning order to investigate its potentially internal features. Like previous specimen, subcomplete articulated skeleton identified B. holotype. Surprisingly, this is almost identical that Thaumastosaurus gezei, an Eocene anuran from Western Europe other specimens mummy series previously assigned. few differences between skeletons highlight ontogenetic intraspecific variations, making T. gezei junior synonym creating new combination servatus. Given association with described specimens, redescribed probably same time interval as gezei. Previous phylogenetic analyses assigned Ranoides, natatanuran affinities. Using data newly we tested further taxonomic Our confirm position, identify Natatanuran member Pyxicephalidae (currently endemic equatorial Africa) more precisely, stem-Pyxicephalinae. This result confirms origin Thaumastosaurus, African herpetofauna occupying before Grande Coupure at Eocene/Oligocene transition.