Leiochrides yokjidoensissp. n., collected from the sublittoral muddy bottom in southern Korea, is described as a new species. The taxonomic status of the monospecific genus Pseudomastus has been a subject of controversy for many years, as its characteristics overlap those given in recent generic definitions of Leiochrides. The results of a comprehensive review and comparison regarding the two genera, based on previous records showed minor differences. In this study, a detailed description of L. yokjidoensissp. n. is given and a comparison with closely related species is tabulated and discussed.The taxonomic status of Pseudomastus is discussed and the genus placed in synonymy with Leiochrides.
Keywords: Korea; Leiochrides yokjidoensis sp. n.; Polychaeta; Scolecida; Sedentaria; morphology.