Original specimens and type localities of early described polychaete species (Annelida) from Norway, with particular attention to species described by O.F. Müller and M. Sars

Early descriptions of species from Norwegian waters are reviewed, with a focus on the basic requirements for reassessing their characteristics, in particular, by clarifying the status of the original material and locating sampling sites. A large number of polychaete species from the North Atlantic were described in the early period of zoological studies in the 18th and 19th centuries. The descriptions were often short or referred solely to general characteristics, which by today’s standards are considered inadequate for species discrimination. As a result, a number of taxa among the so-called ‘wellknown and widely distributed’ species have later been confused with morphologically similar species. Close to 100 presently valid species were described from Norwegian waters before 1900. The most prolific contributions were made by O.F. Müller (with about 20 species from 1771–1776) and Michael Sars (with more than 50 species from 1829–1872). Other authors in the 19th century included Anders Ørsted, Heinrich Rathke and Gerhard Armauer Hansen. Descriptions were mostly in Latin (O.F. Müller) or in Norwegian or Danish with the diagnosis in Latin (M. Sars and contemporary naturalists). Original material from O.F. Müller is not known to exist. Original material from M. Sars and contemporary scientists does still exist, but is often not identified as original (‘syntypes’) and is occasionally spread over several museum collections. Locating original sampling localities (‘type localities’) has been achieved by combining information from various literature sources, labels of original material (when extant), and knowledge of historic place names