The First Report of a Trematodes Infection in Purple Shell, Rapana Venosa, in Korea

The large gastropod purple shell, Rapana venosa, inhabit in the western and southern coasts of Korea at a depth of approximately 10m. Identification of trematodes found in R. venosa from Sihwa lake, Gyeonggi-do, Korea, was conducted in this study. Trematode infection sites were examined using light microscope and genomic DNAs were extracted from the infected tissues of boiled R. venosa. Mitochondrial cytochrome c oxidase subunit 1 region (mt COI), internal transcribed spacers rDNA regions (ITS1-5.8S-ITS2) and 28S rRNA region of the trematode DNA were amplified by polymerase chain reaction (PCR), and compared with those already registered in GeneBank. Cercaria and redia of trematodes were found by light microscopy. Although the DNA sequence of mt COI gene did not match with the Parorchis sp. mt COI sequence, there was a high genetic similarities of ITS1-5.8S-ITS2 and 28S rRNA genes with those of Parorchis sp. (ITS: 97%, 28S: 99%). The phylogenetic analysis also showed our samples were closely clustered with Parorchis sp. All of these data suggest that our samples found in R. venosa are Parorchis sp., but further studies such as electron microscopic observation with fresh samples will be necessary for clear identification at the species level.