The “indo-pacific seahorses”, Hippocampus kuda which had been reared in one of the private commercial aquaria for exhibition were sent to the laboratory for diagnosis. Feces and intestinal contents from 5 seahorses were examined microscopically and revealed numerous scuticociliates. We identified the species of scuticociliate by light (wet mount) and scanning electron microscopy, PCR (polymerase chain reaction) and sequencing. This paper reports the first identification of scuticociliate Philasterides dicentrarchi from seahorse in Korea. Key words: Indo-pacific seahorse, Philasterides dicentrarchi, scanning electron microscopy, polymerase chain reaction, sequencing.
