2023 年 58 巻 2 号 p. 71-73
A dead nematode was recovered from the swimbladder of a one-year old cultured Japanese amberjack Seriola quinqueradiata. Microscopically, the nematode had many bosses on the body surface and contained mass of larval nematodes inside the body, suggesting the parasite was a mature Philometroides seriolae. Molecular analysis of its body part confirmed the identity of the parasite. This is the first record of infection site of this nematode beside the skeletal muscle from the fish host. The amberjack had most likely been infected with the nematode before introduced to the farm. The possibility of errant parasitism in this case is discussed.