l^rOC?^ Vol. 82, pp. 43-62 29 May, 1969 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON THE GENERA POLYEUNOA McINTOSH, HOLOLEPIDELLA WILLEY, AND THREE NEW GENERA (POLYCHAETA, POLYNOIDAE) By Marian H. Pettibone Smithsonian Institution, Washington, D. C. The polynoid genera Polyeunoa Mcintosh (1885) and Holo-lepidella Willey (1905) have been used by various polychaete workers to include identical species. The species referred to the two genera are generally elongate, with numerous segments and numerous pairs of elytra. In addition, the lateral antennae are inserted ventrally on the prostomium, i. e., harmothoid type of insertion. The elytra in the posterior segments may be rather irregularly arranged in these elongate species. In a study of numerous specimens of the type-species of Polyeunoa, P. laevis Mcintosh, Bergstrom (1916) pointed out the unusual variability in the number and arrangement of the elytra. At the same time, he suggested that Polynoe tuta Grube and Hololepi-della commensalis Willey might both be referred to Polyeunoa, since these two species also show variability in the arrange-ment of the elytra in the posterior regions. The elytral variabil-ity was well shown for Polynoe tuta (as Halosydna) by John-son (1901). Augener (1918, 1922) suggested that Hololepidella be used for polynoids with a harmothoid prostomium and nu-merous elytra extending along the body. Neither Bergstrom nor Augener emphasized differences in the arrangement of the ely-tra in the anterior region or other parapodial differences. Berke-ley and Berkeley ( 1948) and Pettibone ( 1953), following Berg-strom, referred Polynoe tuta Grube to Polyeunoa Mcintosh; emended Bergstrom. The same species was referred to Holo-lepidella, following Augener, by Annenkova (1937), Hartman (1948), and Uschakov (1955). Similarly, Polynoe nigropunct-ata Horst was referred to Hololepidella by Day (1957)-^nd to, 3— Prog. Biol. Soc. Wash., Vol. 82, 1969
BioStor
