Not stated. The name if referring to parapodial structure seems a contradiction as Polynaineris is distinguished by having NO postsetal papillae, whereas Naineris sensu stricto, may have up to three.
Pettibone, Marian H. (1957). North American genera of the family Orbiniidae (Annelida: Polychaeta), with descriptions of new species. Journal of the Washington Academy of Sciences. 47(5): 159-167. available online athttp://biodiversitylibrary.org/page/39753529 Available for editors [request]