Life cycle of Phacellophora camtschatica (Cnidaria: Scyphozoa)

Abstract. Gelatinous zooplankton play important roles in marine ecosystems and at times can have significant impacts on human activities. Many scyphozoans have enigmatic life cycles and the specific habitat for benthic life history stages is unknown. This is especially true for many of the large surface-cruising scyphomedusae of the northeast Pacific Ocean. Phacellophora camtschatica belongs to the family Ulmaridae and is known to have scyphistomae in the life history. However, the life cycle of P. camtschatica has not been formally described. Here the life cycle of members of P. camtschatica is described based on laboratory observations and compared with early life history stages in the scyphomedusa Aurelia labiata .