Systematic review of Late Jurassic sauropods from the Museu Geológico collections (LIsboa, Portugal)

Abstract

The Museu Geológico collections house some of the first sauropods found in the Upper Jurassic sediments of the Lusitanian Basin, including the Lourinhasaurus alenquerensis and Lusotitan atalaiensis lectotypes, previously considered as new species of the genera Apatosaurus and Brachiosaurus, respectively. Several fragmentary specimens have historically been referred to those taxa, but for the most part of these systematic attributions are not supported herein, excluding a caudal vertebra from Maceira (MG 8804) considered as cf. Lusotitan atalaiensis. The material housed in the Museu Geológico comprises remains of non-neosauropod eusauropods (including turiasaurs) and neosauropods (indeterminate neosauropods, diplodocids, camarasaurids and basal titanosauriforms). Middle caudal vertebrae with lateral fossae, with ventral hollow bordered by pronounced ventrolateral crests and, which are quadrangular in cross-section, indicate for the presence of diplodocine diplodocids in the northern part of the Lusitanian Basin Central Sector during the Late Jurassic. A humerus collected from Praia dos Frades (MG 4976) is attributed to cf. Duriatitan humerocristatus suggesting the presence of shared sauropod forms between the Portugal and United Kingdom during the Late Jurassic. Duriatitan is an indeterminate member of Eusauropoda and the discovery of new material in both territories is necessary to confirm its systematic position. The studied material is in accordance with the previously recorded sauropod fauna in the Portuguese Late Jurassic, which includes non-neosauropod eusauropods (including turiasaurs), diplodocids and macronarians (including camarasaurids and basal titanosauriforms).