A specimen of the pelagic polychaete Pedinosoma curtum Reibisch (Lopadorhynchidae [sic]) is described from the North-West Pacific. It differs from the Atlantic specimens of the species in longer aciculae, larger antennae as compared with palps and pigmentation of the dorsal cirri. A late larva of Pedinosoma ?olaris sp. nov. is described from plankton of the Arctic Basin (depth 2000-1000 m). The distinctive characters of the new species are: podial lobes, aciculae and compound chaetae present on the tentacular segment, the absence of cirrophores of the tentacular and ventral podial cirri, the podial cirri arranged on the podial process, and a well-developed pygidium bearing anal cirri. An additional diagnosis of the genus Pedinosoma Reibisch is provided.