Gonkoken

Phylogeny: Dinosauria > Ornithischia > Genasauria > Neornithischia > Cerapoda > Ornithopoda > Iguanodontia > Ankylopollexia > Styracosterna > Hadrosauriformes > Hadrosauroidea

Overview: Described in 2023, the genus Gonkoken is based on a set of partial remains unearthed in the south of Chile. The first of these bones were found around a decade prior, within the sediment of the Dorotea Formation, dated to fairly late into the Cretaceous Period. Other notable dinosaurs from the Dorotea would include the odd, tiny ankylosaur genus Stegouros, while fossils of as of yet unnamed sauropods, megaraptorids, and unenlagiine dromaeosaurids have also been found. Fossils of marine reptiles, mammals, and fish are also present. The generic name of Gonkoken is translated from Tehuelche into English as “like a duck” or “like a swan”, Tehuelche being the language of the native people within the area where it was found. It’s a fitting name for a dinosaur belonging to the superfamily Hadrosauroidea, to which the famous “duck-billed” dinosaurs belonged.

Gonkoken appears to have been less derived than the true hadrosaurid “duck-bills”, but it was one of the more derived non-hadrosaurid members of the Hadrosauroidea. Studies have found it to be a potential member of the clade Hadrosauromorpha. Derived hadrosauroids were once thought to be absent in South America and native only to the northern hemisphere, but fossils of hadrosaurids like Kelumapusaura reveal this was untrue. Kelumapusaura belonged to the clade Austrokritosauria (a part of the hadrosaurid subfamily Saurolophinae). Gonkoken doesn’t belong to this lineage, so it being present when and where it was shows us that hadrosauroids were fairly diverse, even within South America. Within its local environment, Gonkoken probably filled a niche similar to most of its relatives, grazing on low-level vegetation, possibly in herds or groups for protection.