In 2002, when this process had not yet been completed, Ronan Allain, after having dedicated a thesis to it, named the find as a new species of "Poekilopleuron": "Poekilopleuron? valesdunensis". The specific name referred to the nearby ancient battlefield of the Battle of Val-ès-Dunes, where William the Conqueror had in 1046 defeated his enemies. The naming paper also contained a description of the skull. The question mark after the generic name already indicated the assignment to "Poekilopleuron" was tentative. By 2005, Allain had come to the conclusion that the new species was not part of "Poekilopleuron". He therefore created the new genus name "Dubreuillosaurus" for this species, the name honouring the Dubreuil family. The type species of the genus is the original "Poekilopleuron valesdunensis", the "combinatio nova" is "Dubreuillosaurus valesdunensis". The 2005 paper also contained a description of the postcranial skeleton.