This is larval-fish of Caristius macropus (Bellotti, 1903) . Body length was SL20 mm. Larval-fish is known to be with jellyfishes of Siphonophorae such as Agalma okenii , Apolemia uvaria and Rosacea cymbiformis . This time it was with A. okenii . Since it departs from jellyfish when diver approaching too much, dependency on the host seems to be low. Adult is bathypelagic . It's habitat depth range 250 - 1420 m . Larvae habitat from surface. C. macropus has lateral line, but closely related species of Paracaristius nudarcus has not lateral line. The width of the eyes and the maxilla is narrow. Dorsal soft rays: 33-35 , Anal soft rays: 21-23 . Larval-fish of Manefish Larval-fish of Manefish REFERENCES: fishbase.org http://www.fishbase.org/summary/11831 Distribution Map(fishbase.org) http://www.aquamaps.org/receive.php?type_of_map=regular Nakabo, T. (ed.), 2013. Fishes of Japan with pictorial ke...