A PRELIMINARY NOTE ON THE FIRST TETRAPOD TRACKWAYS FROM THE LITHOGRAPHIC LIMESTONES OF LAS-HOYAS (LOWER CRATACEOUS, GUENCA, SPAIN)

Although famous as a fossil. lagerstatte that has produced numerous we ll-preserved vertebrates, recent discoveries indicate that the lithogr aphic limestones of Las Hoyas (Calizas de la Huerguina Formation) also contain vertebrate trackways. We herein report on at least two distin ctive tetrapod track types tentatively assigned to crocodilians and to turtles. Turtle tracks are isolated while the crocodile ones are form ing a trackway showing an animal walking with a very regular step and stride length on an emergent surface. It is interesting to note the si milarity between the inferred turtle tracks from Las Hoyas and those f rom the Late Jurassic lithographic limestones of Cerin, France. The oc currence of tracks in both environments suggests that the ichnofaunas are similar.