Allozyme comparison of three nemertean species of the genus Oerstedia (Nemertea: Monostilifera) from the Sea of Japan

Three species of hoplonemerteans, all very similar in external features (Oerstedia oculata, Oerstedia phoresiae, and Oerstedia zebra) were compared using 23 allozyme loci. The results of this study confirm the specific validity of O. phoresiae. At 20 of the 23 loci this species shares no common alleles with O. oculata (D = 2.718) and at 21 of the 23 loci O. phoresiae shares no common alleles with O. zebra (D = 2.730). Most likely O. zebra is a color variation of O. oculata, because these species are very similar in their allozyme markers (D = 0.000).