Oblitosaurus

MEANING: Forgotten lizard

PERIOD: Late Jurassic

CONTINENT: Europe

Like other ornithopods, Oblitosaurus had a short neck and a beak which it used to feed on plants. The thumb claws were adapted into small conical spurs, and it could likely walk quadrupedally or bipedally. Oblitosaurus could reach around 7 m in length, making it the largest known European ornithopod of the Jurassic.

Abstract from paper: Ankylopollexia was an abundant and diverse clade of ornithopods present in North America, Europe, Africa, and Asia from the Late Jurassic to the Late Cretaceous. However, the relationships between the basal ankylopollexians are poorly understood. A new ankylopollexian ornithopod genus and species is described here, based on a dentary tooth, an ungual pollex of the manus, and an almost complete left hindlimb. The fossils come from deposits of the Villar del Arzobispo Formation (upper Kimmeridgian–Tithonian). Phylogenetic analysis revealed that Oblitosaurus bunnueli gen. et sp. nov. is the basalmost member of Ankylopollexia, together with Draconyx loureiroi. Furthermore, these results have relevant taxonomic implications for the genus Camptosaurus, being the first phylogenetic analysis to support the monophyly of Camptosaurus species. The estimated size of Oblitosaurus bunnueli suggests that it is the largest ornithopod described in the Upper Jurassic of Europe and one of the largest around the world, and could be the trackmaker of large ornithopod tracks found in the Upper Jurassic of the Iberian Peninsula. This discovery increases the known ankylopollexian diversity in Iberia, revealing the presence of an Iberian basal ankylopollexian clade that does not appear to be present in the contemporaneous outcrops of North America.

Oblitosaurus is from the Late Jurassic. The Late Jurassic was a dynamic period, spanning from about 162 to 143 million years ago. The continents were continuing to drift apart, and the supercontinent Pangaea had fully split into Laurasia in the north and Gondwana in the south. This continental rearrangement led to the formation of large inland seas and shallow coastlines that fostered diverse ecosystems. The climate during the Late Jurassic was warm and humid, with lush forests of conifers and ferns that stretched across much of the continents, creating a rich ecosystem where dinosaurs flourished the dominant land animals.

Dinosaurs continued to diversify through the Late Jurassic, with some of the most famous species evolving in this time. Many well-known sauropods, such as Brachiosaurus and Apatosaurus roamed the land, exhibiting niche partitioning with their selectively distinct neck positions. Alongside them, stegosaurs became widespread, their plates and spikes making them one of the era's most recognizable groups. Theropods like Allosaurus and Ceratosaurus were the apex predators, evolving large, powerful bodies and sharp teeth that allowed them to hunt the gigantic herbivores. The early evolution of birds was taking place, setting the stage for the numerous species that would fill the skies in the eras to come.

Unlike the dramatic mass extinctions that marked the beginning and end of the Mesozoic, the Jurassic Period ended without a sharp boundary. As the continents continued to drift, ecosystems gradually transformed into unique habitats that supported the more specialized dinosaur species of the Cretaceous.

Oblitosaurus is an ornithopod. Ornithopoda is a clade of ornithischian dinosaurs that started out as small, bipedal running grazers and grew in size and numbers until they became one of the most successful groups of herbivores in the Cretaceous. They dominated the North American continent, then spread to Asia and eventually the southern hemisphere toward the end of the Cretaceous. Their major evolutionary advantage was their batteries of teeth, which allowed them to process vegetation in an extremely efficient way. Ornithopods were a diverse group, and included the hadrosaurs, which continued to dominate until the Cretaceous–Paleogene extinction event, which wiped out all non-avian dinosaurs.