A new varanoid squamate from the Early Cretaceous (Barremian–Aptian) of Burgos, Spain

Abstract

A new anguimorph lizard from the late Barremian–Aptian of the Salas de los Infantes area (Cameros Basin, Iberian Peninsula) is described here as Arcanosaurus ibericus gen. et sp. nov. It corresponds to the first squamate remains from the Burgos Province. The unique combination of morphological and microanatomical characters enables us to erect a new genus and species that we tentatively assign to Varanoidea despite the strange seemingly absence on the axis of a posterior hypapophysis. The combination of both microanatomical and geological data suggests an essentially terrestrial mode of life. This discovery reveals itself particularly interesting concerning the evolutionary history of varanoids as this new Spanish taxon might correspond to the oldest terrestrial varanoid known to date.