Evidence of large pliosaurids in the late Valanginian of Colombia

Abstract

The fossil record of Lower Cretaceous pliosaurids, particularly from the Valanginian is still poorly known globally, hindering efforts to reconstruct their evolution and palaeogeographical distribution within a broader time frame. Here, we describe an isolated cervical centrum (14 cm maximum diameter) of a pliosaurid belonging to a Brachaucheniinae gen. et sp. indet., from the Lower Cretaceous (upper Valanginian) Rosa Blanca Formation in Zapatoca, Colombia. The presence of large brachaucheniines in the Rosa Blanca Formation suggests that these large pliosaurids were part of the abundant and diverse fauna that inhabited the northwestern margin of Gondwana during the Early Cretaceous and extends their record in northern South America from the Barremian to the late Valanginian. These pliosaurids potentially acted as top predators in the food chain of lower latitude shallow marine environments. This discovery contributes new data to the taxonomic and chronostratigraphic framework of Early Cretaceous marine reptiles from the Proto-Caribbean domain.