A mesoparasitic copepod, Serpentisaccus magnificus Brasiola, 1979 (Siphonostomatoida: Pen- nellidae) is recorded based on a single postmetamor- phic female specimen from a reared elegant firefish, Nemateleotris decora Randalle and Allen (Perci- formes: Ptereleotridae), in the tank of Kagoshima City Aquarium, Kagoshima Prefecture, southern Japan. The fish was recently collected from the Philippines and purchased by the Kagoshima City Aquarium. Nema- teleotris decora is a new host for the copepod.

いおワールドかごしま水族館のアケボノハゼ Nemateleotris decora (スズキ目:クロユリハゼ科)飼育個体から得られた 寄生性カイアシ類リュウノヒゲ(新称) Serpentisaccus magnificus(管口目:ペンネラ科)(上野大輔 ・大川内浩子・出羽尚子・今北大介)