First Record of the Family Polygordiidae (Annelida: Polychaeta) in Korean Fauna

Polygordiidae is recorded as a new record in the Korean fauna. Twenty-three specimens of Polygordius pacificus were collected from the low intertidal zone with coarse sandy bottom on the eastern coasts of Korea. Morphologically, there was no doubt that the specimens are close to the holotype of P. pacificus, particularly due to the presence of elongated and longitudinal pygidial glands, and the length to width ratio. The prostomium of the Korean specimens have a rounded shape that is similar to subsequent research using scanning electron microscope. The DNA sequence comparison of the mitochondrial cytochrome c oxidase subunit I (COI) between Korean and Japanese population supports the identification of present specimens.