Larvae of deep-sea chemosynthetic ecosystem animals in captivity

Larval dispersion and recruitment of vent and seep animals are important to maintain species composition including endemic fauna. Rearing studies need enormous amounts of time, however, they produce much biological data. The larval data of vent and seep animals in this study will be important data for identification and larval dispersion. Many species of deep-sea chemosynthetic animals were collected and kept on board ships and in aquaria at atmospheric pressure. Larvae of several species of deep-sea chemosynthetic animals have been observed in aquaria: squat lobster Shinkaia crosnieri and Munidopsis myojinsinsis, vent crab Gandalfus yunohana, vent shrimp Opaepele loihi, vestimentiferan tube worms Lamellibrachia satsuma, Lamellibrachia sp. and Alaysia spp, vent and cold seep mussels Bathymodiolus platifrons and B. septenderium and vent flat fish Symphurus thermophilus. Embryonic development of several vent animals tends to be accelerated in higher temperatures. Such species larvae or eggs rise up to upper water layers by buoyancy or positive swimming. They may then be transferred to other habitats by ocean currents. Those larvae have eyes and may be active predators in the mid water, which is rich in prey and has higher temperatures than bottom layers. On the other hand, larvae or eggs of tube worms and mussels may be trapped in the circulation of water around their habitats and thus these larvae can acquire symbionts easily.