Of German princes and North American rivers: Harlan's lost mosasaur snout rediscovered

Abstract

The lost snout of Richard Harlan's specimen of Mosasaurus missouriensis has been rediscovered in the vertebrate palaeontology collections of the Muséum national d'Histoire Naturelle (MNHN) in Paris, France. The specimen (MNHN 9587) bears the handwritten description, 'Amérique du Nord. Par M. Harlan', which translated reads, 'North America. By/From Mr. Harlan'. Accession information indicates the specimen was a gift to the museum prior to 1860 and was likely gifted from Harlan's estate after his death. We examine the available history of the collection of the specimen present a description of the rediscovered snout, and demonstrate conclusively the conspecificity of M. maximiliani Goldfuss, 1845 and M. missouriensis (Harlan, 1834a) by providing a revised diagnosis of the taxon.