New information about the stratigraphic position and age of the sauropodAragosaurus ischiaticusfrom the Early Cretaceous of the Iberian Peninsula

Abstract

The sauropod Aragosaurus ischiaticus Sanz, Buscalioni, Casanovas & Santafé, 1987 was the first dinosaur to be described in Spain. The holotype was recovered from the site of Las Zabacheras (Galve, Teruel province). This site has traditionally been situated in the El Castellar Formation (in the lower part of the Wealden facies). Recently, it has been proposed that the remains of Aragosaurus stem from the Villar del Arzobispo Formation (late Tithonian-upper part of the early Berriasian), which would mean that the sauropod was almost 15 million years older than previously thought. Detailed field work has been carried out, making it possible to pinpoint the position of the low-angle unconformity between the Villar del Arzobispo Formation and the El Castellar Formation. This unconformity originated as a result of block tilting that occurred during the early stages of the Early Cretaceous rifting episode. The upper levels of the Jurassic sequence (i.e. the Villar del Arzobispo Formation) were exposed to erosion and karstification, leading to the formation of a discontinuous conglomeratic level. This level has been locally preserved at the bottom of the Wealden syn-rift sequence (i.e. the El Castellar Formation). The results of our detailed mapping demonstrate that the Aragosaurus holotype was found in the lower part of the El Castellar Formation. Moreover, our revision of the existing datings suggests that the El Castellar Formation as a whole is Valanginian?-early Barremian in age. Given that Aragosaurus was located in its lower part, it is probably Valanginian?-Hauterivian in age.

Manus Track Preservation Bias as a Key Factor for Assessing Trackmaker Identity and Quadrupedalism in Basal Ornithopods

“…The top of the formation in Galve is probably early Berriasian. In the village of Galve this formation represents transitional deposits from shallow marine platform to terrestrial palaeoenvironments ([27], [33], [34] and references therein).…”

“…1 and 2). Lithologically, these levels are mainly fine-grained sandstones (in levels 2 and 3 the grain size is smaller than that of levels 1 and 4) that were deposited in a coastal plain setting [27], [33], [34]. The new area cleaned in 2007 (mainly the upper part of Fig.…”

The anatomy, phylogenetic relationships, and stratigraphic position of the Tithonian-Berriasian Spanish sauropod dinosaurAragosaurus ischiaticus

“…This view has recently been defended by Canudo et al . () based on the presence of synsedimentary faults on the discontinuity between the Villar del Arzobispo and El Castellar formations, and on charophyte and palynological data; however, as outlined below, there are a number of problems with these interpretations of the data, and we here provide a revised view of the geology of this area.…”

Palaeodiversity and evolution in the Mesozoic world

“…Up to six contributions from the Cretaceous, with relevant information to the Iberian vertebrate fossil records, are presented herein. For instance, Alonso et al (2018) describe a new fossil site located near Estercuel (Teruel, Spain) from the Oliete sub-basin, in the Lower Cretaceous (Barremian) Blesa Formation that is interpreted as a coastal-transitional depositional environment (Canudo et al 2012). Similar to other sites from this formation, this fossil site contains an important tetrapod diversity.…”