Asociación de huellas de pterosaurio en el yacimiento de Los Tormos (Soria, España): implicaciones icnotaxonómicas

Abstract

The Oncala Group of the Cameros Basin provides one of the largest collections of pterosaur tracks in the world. 6 ichnospecies have been defined so far, some of which coexist in the same tracksite. After cleaning various levels of tracks from Los Tormos tracksite (Soria, Spain), new tracks of these reptiles have been found belonging to four different morphotypes at that same level, which do not correspond with other two types of a lower level. The ichnites are assigned to two well known ichnospecies (Pt. palacieisaenzi and Pt. cidacoi), two others possibly could be assigned to already existing ichnospecies (Pt. longispodus and Pt. nipponensis) and two morphotypes are unidentified, one of which possibly belongs to a new ichnogenus and ichnospecies. The simultaneity of different ichnospecies in the same tracksite suggests that some of the various types of pterosaurs could live in the same ecological niche, just as they do nowadays, for example, a great diversity of birds in the Guadalquivir marshes (Doñana National Park). The study of these tracks and their potential trackmaker suggest that: a) The diagnosis of the ichnogenus Pteraichnus should be amended because it reflects the general description of all virtually existing pterosaur ichnites; b) pterosaurs could move occasionally putting all their weight just on their toes.