Some areas of the world are particularly rich in dinosaur fossils, and while some finds are spectacular or of particular scientific importance, some are just downright confusing. A new discovery in Mongolia fits into the latter category, with an unusual fossil of a theropod dinosaur hand that has some peculiar features.
At the Pigeon Hill site, of Morin Dawa Daur Autonomous Banner, Hulunbuir City, Inner Mongolia Autonomous Region, China, a research team have discovered new material belonging to a small-bodied theropod dino, including a complete hand, some ribs, and part of a limb.
The fossil is thought to be around 121 million years old, from the time of the Early Cretaceous. Owing to the unusual structures present within the hand the team think this is a brand new species, and have named it Migmanychion laiyang. Currently, they suggest that the fossil is part of the coelurosaurian clade Maniraptora, which eventually evolved into the ancestors of modern birds.
The structure of the hand is different from all other known species of theropod, giving rise to the question of where this new species fits in. The size in general, as well as the ossified carpometacarpus, show a clear difference from other avialian fossils found in the same area.
Oviraptorosaurs, known for their feathers and similarities to birds, and therizinosaurs do have some structural similarities – as demonstrated by previously found fossils – to the new theropod fossil.
The unusual nature of the new fossil also bears a resemblance to another fossil finding discovered in Japan, Fukuivenator paradoxus. The team stress that this initial classification placement is tentative and plan to keep looking for more fossils to better discover where this new species fits into the dinosaur taxonomy.
The study is published in Cretaceous Research.