A revision of the theropod dinosaur Camarillasaurus cirugedae from the Early Cretaceous of Spain

在上侏罗纪和下白垩纪，欧洲主要被陆表海覆盖，因此陆生动物群主要局限于几个较大的岛屿。然而，最近的地理分析表明，欧洲代表了当时亚洲，非洲和北美之间的陆地动物群的重要“转盘”。下白垩纪的一个重要岛屿是伊比利亚，包括今天西班牙和葡萄牙的大部分地区。在过去的30年里，来自西班牙的早白垩世恐龙越来越为人所知，特别是鸟臀目和蜥脚类恐龙，已经为我们了解当时的欧洲恐龙动物群及其地理关系提供了重要数据。然而，人们对兽脚亚目恐龙的了解要少得多;除了在拉斯霍亚斯的层状石灰岩中保存得特别好的拟鸟龙类Pelecanimus和Carcharodontosaur Concavenator，最近只有一个分类群，Camarillasaurus cirugedae，在Barremian Camarillas Formation中被描述。后一个分类群是基于一个不完整的颅后骨骼，并被确定为一个基底角龙类，具有重要的意义，为这个分支的进化和多样性。然而，申请人对这一材料的初步研究突出了对遗骸的原始解释和角鼻龙鉴定的几个问题。此外，对该地点的访问，从那里通过表面收集恢复了原始材料，表明有可能恢复更多的材料。因此，当前项目的目标是完全发掘圆顶龙的模式产地，并修订该分类群的解剖学和系统发育位置，这将使我们更好地了解它对我们了解早白垩世欧洲恐龙动物群及其地理关系的重要性。

Europe was mainly covered by epicontinental seas during the Upper Jurassic and Lower Cretaceous, so that terrestrial faunas were mainly restricted to several larger islands. Nevertheless, recent biogeographic analyses indicate that Europe represented an important "turntable" of terrestrial faunas between Asia, Africa, and North America at that time. One of the important islands in the Lower Cretaceous was Iberia, which included most of present day Spain and Portugal. Lower Cretaceous dinosaurs from Spain have become better known in the past 30 years, and especially ornithischian and sauropod dinosaurs have already yielded important data for our understanding of European dinosaur faunas of that time and their biogeographic relationships. However, theropod dinosaurs are much more poorly known; apart from the exceptionally preserved ornithomimosaur Pelecanimimus and the carcharodontosaur Concavenator from the laminated limestones of Las Hoyas, only one further taxon, Camarillasaurus cirugedae, has recently been described from the Barremian Camarillas Formation. This latter taxon is based on a fragmentary postcranial skeleton and was identified as a basal ceratosaur, with important implications for the evolution and diversity of this clade. However, a preliminary study of this material by the applicant highlighted several problems with the original interpretations of the remains and the identification as a ceratosaur. Furthermore, a visit to the site, from where the original materials were recovered by surface collection, demonstrated that there is potential to recover more material of this taxon. The objectives of the current project are thus a complete excavation of the type locality of Camarillasaurus and a revision of the anatomy and phylogenetic position of this taxon, based on both the original remains and newly discovered elements.This will lead to a better understanding of its importance for our knowledge of Early Cretaceous European dinosaur faunas and their biogeographic relationships.