Four new species of coral- and rock-boring polychaetes Daylithos (Annelida, Flabelligeridae) from the Pacific Ocean

Four new species of Daylithos (Flabelligeridae, Annelida) are described, based on specimens collected from rocks and corals of Japan and Malaysia. Daylithos, contains one species, D. parmatus, currently reported from Japan. However, the specimens described in previous reports were unable to be located and thus deemed lost. Therefore, it was unclear whether the specimens described as D. parmatus in those studies were, indeed, the species. In Malaysia, D. parmatus has also been known as popular species from corals. The specimens collected from Langkawi (Malaysia) showed clearly different characters from D. parmatus and other congeners. In this study, we describe four new species, Daylithos japonicus, D. amamiensis, D. sugashimaensis and D. langkawiensis, based on newly-collected specimens from several part of Japan and Malaysia. These new species can be discriminated from other congeners by body colour, presence of eyes, shape of dorsal shield, length of caruncle and arrangement of neurochaetae. We have also provided mitochondrial cytochrome c oxidase subunit I sequences of the new species.